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ED 219 '.631, CB 03.3 392' J

TITLE RadiolOgical Defense Manual.

INSTITUTtON 1 Defense Civil Preparednets Agency (DOW', Wishington: D.C. REPORt NO' CPG-2-6.2 PUB DATE Jun 77 . NOTE 202p.

EDRS PRICE MFOI/PC09 Plus Pottage.

DESCRIPTORS *Civil Defense; *Emergency Programs; Measurement; . Measurement Equipment; NuclearsEnerg; *Nuclear. ..-J, Physict; *Nuclear Warfare; Planning; Postsecondary 1

Education; Radiation Biology;'.*Radiatfon Effects; .

Safety Equipment . - IDENTIFIERS Fallout; Radiation Monitors; *Radioactivity

1 ABSTRACT Orfginalsly prepared for use,as a student textbook in Radiological Defense (RADEF) courses, this manuil provides the basic technical information necessary for an understanding of RADEF. It also briefly discusses the need for RADEF planning and expected postattack emergency operations. There ire 14 chapters covering these

major topics: introduction t$ radiological deiense, basib concepts of , nuclear science, effects of nuclear weapons, nuclear radiation measuremanit, radiological detection and measurement instruments,,

radi.dactivd exposure rate calculations, radiological monitoring. . techniques and operations, protection from radiation, radiological decontamination, RADEF,operatione, RADEF planning, and implementing er-,-= RADEF plan. A glossary concludes the manual. ,(YLB)

****************************************11****************************** * Reproductions supplied by EDRS are the hest that can be made from the original document. * ***********************************************************************

. ' " 4. .0

CPG 2 -6.2 JUNE 1977

.U.S. DEPARTMENT OF EDUCATION NATIONAL INSTITUTE OF EDUCATION EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC) Alasdc4n.nt has been reproducedas rece,y,eYlrom the ptrson or organization originating it u Minor changrrs have bein mad* to improve reproduction quality

Points of view or opimons stated in this docu . mutt do not necessarily represent official NIE position Or policy.

DEFENSI cImp,Rgek EDNESSAGENCY DEPARTMENT )isk= ,, -1

e' . . . . , . .

RADIOLOGICAL DEFENSE MANUAL

*(Supersedes M :11.22 -2 dated JUNE 1974 which may be used).

DEONSE CIVIL PREPAREDNeSAGENCY DEPARTMENT OF' DEFENSE PREFACE

This:Manual provides the basictechnical information necessary foran understanding of Radiological Defense (RADEF) and briefly . discusses the need,for,RADEFplanning-and expected postattack emergencyoperations. It had originally been preparedby the Defense Civil Preparedness Agency (DCPA) - for use as a student.textbook in Radio- it logical Defense Courses. e Tbis technical Malal is.snOt intendedto \ provide complete R operational pro- ) cedutes or direction for thedevelopment of RADEF plans and organizations.,Such, detailed guidance will be found inother DCPA publications. t

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TABLE OF CONTENTi Chapter Page 1 INTRODUCTION TO RADIOLOGICAL DEFENSE 1 Discusses the nature of the radisological threat andthe measures being taken to counteract that threat. 2BASIC CONCEPTS OF NUCLEAR SCIENCE 5 Discusses those factors in nuclear radiation physicswhich RADEF personnel should 'understand in orderto carry out their responsibilities in the ivst effectivemanner. 3 EFFES OF NUCLEAR WEAPONS 25 Describes how nuclear,weapons differ in both degree and kind frorn conventional explosive weapons, and what theeffects of a nuclear exPlosion are, both in sequence an& nattfre. 4 NUCLEAR RADIATION MEASUREMENT 55 To deal with the radiological effects of nuclearexplosions it is vital to be able to detect and/to measure harmful levelsor rates of radiation. This chapter describethe principles by whichwe are able to do this. 5 RADIOLOGICAL EQUIPMENT 69 Describes those radiological detection andmeasurement instrnments constructed on the principles set forth in Chapter4 which are available to the radiological defense program. 6 RADIOACTIVE FALLOUT 8(1 One of the principal effects of nuclearweapons is the production of radioaciive Material Winchcomes back to earth ,in the form of fallout. This chapter tells how fallout is formed,how it iadistributed, how it is a hazard, and how its movement can be predicted. EFFECTS.OF NUCLEAR RADIATION EXPOSURE 97 This chapter tells what happens to the human body wheinsubjected to radiation at varioull levels, and why these biologicaleffects occur. 8EXPOSURE AND EXPOSURE RATE. CALCULATIONS 117 A central concept in dealing with nuclear radiationis the decrease in radiation levels of radioactive fission products withthe passage of time. This chaptet tells how this decreaseor decay may be calculated under various conditions and by various,methods. RADIOLOGICAL MONITORING TECHNIQUES ANDOPERATIONS 135 Describes the objectives of radiological monitoringand hoW those objec- tiyes ate achieved. -10PROTECTION FROM RADIATION 142 ibereare various kinds of 'radiation emitted from fallout..This chapter ekpiains what they are, how they differ, and by whatmeans we may Protect ourselires from them. 11RADIOLOGICAL PEPONTAMINATI ON 153 Describes the general nature ,of radiologicaldecontamination and the prindiplea and phases of decontamination operations. 12 RADEF OPERATIONS 164 Describes the'role of RADEF at each level, ofoperations. Chaptir Page 14RADEF PLANNING 168 We all accept,the need to look before we leap, but why is planning with its cost in money and manhours really of such crucial impontance? This chapter provides some answers to that question.! 14"PAPER PLANNING" OR REAL RADEF 179 A 'plan can be just words or it can be a blueprint for action. The difference lies in the availability of certain skills and knowledge necessary to translate 'the plan into effective action. This chapter discusses what these are. GLOSSARY 185

+15 CHAPTER 1

INTRODUCTION TO RADIOLOGICAL DEFENSE

A strong civil preparednessprogram is dropped on a mixture of military, indus- vital to this nation's security. Today,ev- trial and population targets as both sur- ery citizen iind officials at every level of face and air bursts. The results vary, of government should be concerned with pre- co-urse, but the unmistakable fact re- paring for disasters of all kinds. This book mains that millions of Americans would be. is primarily concerned withone such po- killed outright in any Such attack by the tential disaster; that of a nuclear attack direct effects of blast and fire. The loca- on this country. tions at which weapons were detonated This chapter will show why civilprepar- would suffer unprecedented physical dam- edness is vital to our security by stating age and the fallout radiation from surface the nature of the threat we face and the weapons would affect hundreds of square role that 'an effective preparednesspos- miles in a downwind direction from those ture can play in our national response to bursts. Additional millions of casualties that threat. It will also define whatwe would be caused depending on the amount mean by "radiological defense" and will of fallout protection available in the af- indicate how such defense is organized. fected areas. In one simulated attack in Another objective of this chapter, andper- which 800 nuclear weapons of 3,500 ,mega- haps the most important one, is to explain tons were assumed, there would be about how effective radiological defense requires 97 million people killed either oufrightor trained and dedicated personnel. Wecan- who died subsequently from the direct ef- not develop a radiological defense capabil- fects or from fallout. Another 30 ,million ity unless we can counton all of our citi- would have been injured but would sur- zens to learn something .of the nature of vive while the remaining 67 million out of nuclear radiation and to gainan under- a total population of 194 million would not standing of the measureft thatcan be be affected. ' taken to defend against its effects should 1.3 Three things are worth noting this nation ever face nuclear attack. about this threat. Thez,are: THE NATURE OF THE THREAT First, there is no equivalent in human experience for the destructiveness' of 1.1 Any assumptions abouta possible"'multi-megaron hydrogen weapons. It is nuclear attack Upon the United Statesare worth remembering that all the bombing dangerous since we can never be siiie raids on Germany in World War U .`.. by about a potential enemy's objectivesor 'all the allied forces... together totalldd even specific capabilities. Studies made by but one megaton. the Department of Defense and others for Second, not only arc theweapons in a,, exercise purposes use-attack Patterns 'thatnew dimension of destrUction, but the de-- represent current estimates of weapon livery systems are now in anew dimension size and t4ta1 'yield that could be delivered of effectiveness. Unless on this country in an all out nuclear at- An anti-missile- tack. missile is developed that can not only hit an enemy missile, but hit it almost imme- 1.2Specific attack patterns assume diately aftef it leaves,the launching pad, hundreds of nuclear weapons withmany and further,- can discriminate between millions of tons of TNT equivalentare missile and decoy,,the 'advantage in

1 mpdern sttiategic missile warfare seemsCivil preparedness is apr ime example of a certain to remain with the attacker. This"Passive" capability. ,factor, coupled with the enormous destruc- 1.5 The Strategic. ArmsLimitat ion tivehess of modern weapons, places a Talks (SALT) were designed to -effect a preMium on surprise. balance of pewer among the two primary Third, this hypothetical attack would .-nuclear powersthe United States and product casualties tp more than half of-the Soviet Union. The SALT negotiations our population undei\the conditions then would basically effect this balance by plac- prevailing. If the condftions were changed ing limitations or curbs upon.the "Active" to the extent of providing an effective civil offensive and defensive capabilities "of a preparedness program, the casualtiesnation. It then becomts apparent that, would be reduced to a major degree. assuming theeffectiveriess 'of the SALT negotiations, a nation with a strong "Pas- NOTE - sive" defensive capability occupies a posi- Our system of ethics is based upon the tion of. strength. Herein lies the impor- belief that each individual life is pre- tance of civil preparedness and radiologi- cious. TAis belief underlies all our cal defense. American institutions. It is, in fact, the basic way we differ from systems 1.6Since the civil preparedness pro- embracing totalitarianism, where the gram is a vital element of a meaningful individual' is the servant of the State, "Passive" defensive posture, it is ex- rather than our syStem where govern- tremely iMportant that it be an effective ments derive ".. . their just powers from the consent of the governed.. . ." element with trained personnel ready to This central fact,. which motivates the 'provide an immediate response in a crises government in working for civil pre- situation. Thus,in terms of the 'recogniz- paredness, should not be obscured by statistics,dealing with millions of gas- able nuclear threat, radiological defense ualties. "Megadeath" like "genocide" occuPies a very realistic and substantial are words that spring from systems of role within the United States civil prepar- ,governnient alien to ,our way of life edness program and within the total de- and our system of right and wrong. fensive posture of the nation': Unfortunately, the grim facts of the missile age force us.to consider these terms, 'so hostile to our belief in the supreme value, of the individual. RADIOLOGICAL DEFENSE 1.7In evaluating the results of a hypo- THE ROLE OF CIVIL PREPAREDNESS AND thetical nuclear attack upon the United RADIOLOGICAL ,CIE FE N SE States, seVera/ means of protestion must 1.4 The national defensive posture of a be utilized. Assuming that a crisis period nation incorporates, among other things, or period of marked increased interna- the concept/of "Active" and "Passive" of- tional tension will probably preceed an fensive and/or 'defensive capabilities. "no- actual attack, crisis evacuation proceaures tive" offensive and defensive, capabilities can remove segnfentg of the population include items suCh as a nation's military away from probable high risk areas. Addi- forces and arms, both 'conventional and tionally, to the -extent that it, is available, nuclear, as well as any other capability protection against blast and other direct which represents an "Active" resource for effects should be taken by utilizing availa- implementing and maintaining, an offen- ble shelters. Equally important, however, sive or 6fensive posture. ICBM's, bombis the need in all defensive plans for pro- ers, naval ships, etc., represent obyious tection against nuclear fallout. Radiologi- examples of an "Active" capability. "Pas- cal defense maximizes this type of protec- si.v.e" capabilities, however, are those tion. items lacking the visibility of, a military 1.8Thus, vadiological defense is an ex- force,, but which may contribute signifi- tremely important element of civil prepar- cantly to a nation's defensive capability. edness. Radiological defense is defined as: , 2 ,. 8 The Organized Effort Through needs a large number of fallout monitOr- Detection, Warning, ant ing stations. Some of these stationsmay Preventi4e and Remedial Measures be locate't within, coml.:11unitshelters, 011. To Minimize the Effect of since such shelters form stronpoints of Nuclear Radiation survival and bases of ultini recovery on People and Resources. operationg? Those-communityshelters that provide for extended 'geographic and GENERAL RADIOLOGICAL.DEFENSE communications coverage are particularly REQUIREMENTS suited for serming in the additionalcapac- ity of monitoring stations. 1.9Following are the requirements ofa 1.12 Whether in separate monitoring Kund radiological and civil preparedness .., stations or carrying out monitoringproce- program: , dures from community shelters, the pri- (a) A system of shelters, equipped a.nd mary job of the monitor will be to supply provisioned to protect qur population from information on radiation levels, informa- the fallout effects of a nuclear attack. tion basjc to survival and recovers opera- (b) Organization and planning ofemer- tions. In carrying out their duties, the gency actions necessary to restore a ,func- monitors should receive technical direc- tioning society.' tion and supervision from their organizational, Radiological Defense Officer. THE IMPORTANCE OF SHELTERS RADIOLOGICAL DEFENSE 1.10 Sheltersboth individual and . comniunityare "keys" for survival. This ORGANIZATION fS. because shelter playsa dual role in an 1.13 As stated in `Publif Law 85-606, it effective radiological defense 'program; first, as a shield protecting individuals; is the intent of Congress, in providine funds for radiological defense, that the. and iebond, as a shield protecting theper- reiponsibility for such defense be "vested sons who, bypossessing special knowledge, It' jointly in the Federal Government and the skills, and habits of organization,can com- several States and tHeir political subdivi-- bine to assure the continuing of Ifunc- sions." The ,division of responsibilities tioning, democratic gociety. Thus,a. shel- among governments, which is a central.- ter is not only a passive shield; it is.alsoan feature of our Federal system, is fully 'activ'e element in the system ofcounter- reflected in the organization of radiologi- measures that would have to be taken to cal defense. The DCPA recommended assure the survival of the nation after an pro- attaek. gram describe's in some detail the responsibility, of' each element and level of goir- As radiation l,vels decline, people'tan ernment, and the organization established leave their sh4lters to perform needed to give effect to these levels of risponsibil- tasks of recovery. But whencan they ity. leave their shelters? This and otherques- 1.14In order to make 'the radiological tions, such as determining what the radia- defense program la success, there is need tion 'levels are 'Within the shelter,can be for radiological monitoring stations at. satisfactorily answered inone way only: Federal,State,andlocalfacilities* through accurate measurementor moni-'throughout the nation. Thismeans that toring, there is a need for money to pay for the instruments and eiquipment required; MONITORING AND THE MONITORING there 'is need for mItnagement toassure SYSTEM' that these stations operate effectively and in one coordinated system. But there is 1.11 To assure adecluate measurement!even more need, for trained men and -of-fitdiation levels to. support postattack women who can operate the equipment, do ifittiöiogical.defense operations, the nation( the other specific jobs needed, and provide,

3 9 leaderslkip in radiological defense matters men and women breathe life into plans. on the local level. An essential partof such This is the reason behind the organization local leadership is the training of RADEF of DCPA courses. The courses offer the personnel. , training. If that offerhig is takento, the 1.15, DCPA training courses are.de- fullest potentialthen all the effort, and .. signed to, produce a core of competent ra- planning, and hopes of those deeply con-. diological defense personnel including cerned with protecting our society, from those who will go back to their communi- the President on abwn, will be realized. ties and train others. For without trained For on men and wonien like ourselves, in people, the best laid plans become little)the last analysis, will lie the success of more than complicated dreams.Trained radiological defense program.

2 r." 4. CHAPTER 2

.' BASIC CONCEPTS OF NUCLEAR SCIENCE

We will begin by ending themystery. WHAT are the kinds Of nuclear radia- Since the aim of this book isto lieyouin tion your Xvoik of radiological defense, it is WHAT;is the language essential 'that yOu understand whatyou of nuclear are defending againstnuclear radiation. physics, the terms, signs and symbols used to de- .This, then, is theprfmary objectiveof this chapter: . scribe the world ofpthe atom s and-radiation .40 WHAT is the structure of tpe atom Understanding Nuclear Radiation Wieris the nature of itsparts There-are many kinds of radiation,some HOWdo.these parts behave of which, such .as long and short radio HOWis nuclear ra'diation measured waves, infrared (or heat) radiation, visible- light, and ultraviolet radiationare familiar to all of us. However, nuclear TWOEUNDAMENTASANDA radia- BOMBSHELL tion, the noiseless, odbrless,unseen, unfelt something that can beso deadly seems, as 2.1There are two physical law's,thtstwe Winston Churéhill said of Russia, "a riddle must understand before we talk abart the wiipped.in. mystery insidean enigma". atom. .- Fortunately, this need not 15.64o. A few 2.2 The first of these is knownas the concentrated hours of study will quickly,LAW OF CONSERVATION OF MATTER. make. rtidiation understandable. According to this law, the totalmass of the However, dour job. Were how to stop air material universe remains always the contamination from automobile exbaus, same, regardless of all the.'rearrange- we .would not get too far by confining-c-nients of its component parts. Thiswas ourselyes to the natUre of the exhaust first demonstrated by the brilliant French alone. It' would benecessary to study thephysieist Antoine Lavoisier,, whose'genius fuel, the way the auto engine burnedthe. was cut'snort by the French Revolution. fuel,. aswell as many Other things. Only Lavoisier burned a candle Of known then could we underttand, and possibily weight until it disappeared. He then cope,with,'the factors in the. exhaustweighed the oxygen used by the burning. futnes that were harmful. candle, the wax 'that remained- andthe foul gas (carbon dioxide)eand The-same need exists -with nuclear-rt.t:. water vapor diation: If we are to understand it,we formed by the burning candle. Hefound must see the whole picturerwe must knowibat,the weightof the candle ti;at disap- ' peared and the-weight,of the why as well as the *what ofnuclear the oxygen that radiation. combinee with itequalled the weight of tile carbon slioxide Therefore, to help us understandnu- and water vapor. This -clear radiation, the major objectAre of this is oneAtemonstration4pf the LAWOF CON- chapter, we must also have SERVATION OF MATTER. some grasp of: 2.3 The second 'law of conventional WHAT is meant by 'inptter" and "en- physics is known as the I.:AW OFCON- , ergy" SERVATION OF ENERGY. This law /NO states,that one form of energy Fan be terms new or unclear to you, such as converted to another form, but the total, "ergs". All of these words are included in the,GLOSSARY found at the dnd of amount of energy_in the -uni3,7eree neither-' the text. increases nor decreases. 2.jl. Until 1 05, matter or Mass and gn- POWER IMPLICATIONS, were loo ed at as separitteentities, - 2.7Although no one has succeeded findeed they appear to be. through nuclear fission in converting to 2.5 Then, a young mathematician and energy more than a small fraction Of any physicist working in the Swiss Patent Off- mass, the advantages of nuclear fission ice produced a bombshelL The young man over chemical power (gucti as, comfiustion) was Albert Einstein. He said, in what is are enormous. (See Figure 2.7 for some probably the most important mathemati- examples). For instance, n the fission- cal equation in history, that E Ouals ,mc2, ing of uranium, as in,the bomb dropped or, in plain English, that there is an exact over Hiroshima, only a minute part, of the equivalence between mass and .energy. total mass of 'radioactive substance is Mass can be convrted to energy and, even changed to energybut this release of.A- more strangely, energy can sornetimexbe ergy is gigantic. The Hiroshima hlast wag converted to rnasg. equivalent to 20,000 tons of TNT. This was 2.6 According to Einstein, it is not produced by the fission of 2.2.pounds of mass dr energy as a separate entity, but uranium (since only a minute part of the rather the total mass-energy of the uni- total aetuallf underwent fission, the ura- yerse that remains cortant In his eLlua- nium contained in thebomb was consider- tiOn E = mc2 E stands for energy; in 4rgs, ably more than 2.2 pounds). Why so little generatedby any reaction; m is for "mass" mass can pfoduce so much energy is pre- in grams, lost in anY reaction; and e is the cisely .what \Vas explained in Einstein's. speed of light, equivalent to 3 x 1010 cm per E =m6. formula. second (186,000 miles per second). S. NATURE OF MATTER NOTE - As you read through this and other 2.8About the year 1900 a chemist, If chapiefsgou may meet words and asked to expligth tilt. material world in

'FISSION OF ONE POONO OF URANIUM

A.). PRODUCES AS MuCH ENERGY AS 'COMBUSTION (Y.._

1400 250000 TONS Of COM- GALLOHSO DASCLINE

410,000.000 CUBIC FEET Of NATURAL OAS

FIOURE 2.7.Nuelear energy aa commred with chemical energy. ft FIGURE 2.7Nuclear energy as compared with chemical energy. 1 2. non-technical language, would havespo- example, drinking water is formed by the ken somewhat a:. follows, stressing certain chemical union of twogases, hydrogen and facts that are still valid andare still fun- * oxygen; edible table salt is compounded &mental' toan understanding of more re- from a deadly gas, chlorine, anda poison- . cent discoveries. ous 2.9 The chemist would speak of ELE- 2.15 Whenever a compound isTITO- MENTS, of the ATOM, of MIXTURE§ and duced, two or more atoms of the combining COMPOUNDS, of ATO.MIC WEIGHT and elements join chemically to form the MOL- the PERIODIC TABLE. Let usrtake these ECULE that is typical of the compound. one at a time. The molecule is the smallest unitthat 2.10 Elements.All material is madeup shares the distinguishing characteristic of of one or more efementi. Theseare, sub- a cornpound. - stances that cannot be broken down into A 2.16 Atomic Weight.Hydrogen is. the other and simpler substances by,any lightest element. Experiments havedem- chemical means. Our 1900 vintage chemist onstrated that the oxygen atom is almost 'did not know it, but you willsee later, that exactly 16 times as heavyas the hydrogen it is possible to cause both decomposition atom. Chemists express this truth bysay- and production of certait elementsby ing that oxygen has an ATOMIC WEIGHT means of nuclear reactions. There are now of 16. Through many experiments,the over 100 known basic materials or ele- atdmic weights of the remaining elements ments such as iron, mercnry, hydrogen, have been foundr' etc., that have been discovered and classi- 217 The Periodic Tdble.Figure 2.17 is fied. Some have never been found ina natural environment, but are manma§le. a standard table of the elements. The atomic number of each elementappeass 2.11Iron,: mercury, and hydrogenex- above its chemical symbol. The vertical isting at noriml temPeraturesas a solid, a coluMns represent familygroups. All liquid, and a gas respectivelyare typical membersfrom the lightest to heaviest elements. By heating, a solid element'can of a .family behave likeone another in be changed,to a liquid andeven to a gas. forming (or refusing toPtorm) chemical 'Conversely, by cooling, agaseous element compounds with other families. can be changed to a liquid and even to a .solid. , 2.18 While still essentiallp.correct, this circa 1900 chemiit's view orinatter needs 2.12 The Atorn.The smallest portionof to be supplemented (but not..entirely-re- any eleMent that shares the general char- placed) by an analysis of the atoin. In 1900, acteristics of that element is calledan only a few advanced scientists had become. ATOM, which is a Greek word meaning convinced that the atom is divisible after_;: INDIVISIBLE.PARTICLE. all. This was a neW idea, since theatom 'is 2.13 , Mixtures.Elements,may be 'very small) baying an overall diametei-Of mixed without necessarily tindergoi*any about 10-' centimeters. chemical- change. For example,, if finely powdered iron and sulfurare sti*ivtl and THE ATOM AND ITSBUILDING BLOCKS shaken together, the result is a mixture.- 2.19 Even if it were possible to grind thiS,inix- Small as it is, the atom" proyed to ture to atom-size particles,, the iron atOms be corposed of yet smaller particles. In and the sulfuratoms wonici.,remain dis- fact, as shown in Figure-2.19a, it proved to tinct from each other. be mo*Stly emptyspace, with the actual matter contained in a centralmass. The 1-2.14Compounds.=1),rder certain condi- new knowledge of the nature of the atom tions, however, two ore elementscan has added many terms to those knownto be brought together in sucha way that\our 1900, vintage chemist. Let us take a- they unite chemicallytO form a compound. few.of these terms: and relate them to The resulting substaticemay differ widely some diagrams of Vie atom. The terms from any of in 'component elements.For most useful are NUCLEUS, ELEC- u 7 . 13 er .THE PERIODIC TABLE OF THE ELEMENTS

IA 0 e 2 - . Period 1 1 (... He r H \ II A '. . . . IIIB IVB VB ifr VIB VIIB . 10 3 4 5 6 7 8 9 Period 2 . ' N ) 0 F Ne I LI 'Be Groups # . VIII \, 13 14 IS 16 17 18, 11 12 ' Period 3 I \ Al Si p S ' CI Ar Ma Mg IIIA IVA VA VIA VIIA 1 IB Ifg : 30 31 22 33 34 35 36 19 20 31 22 23 24 25 26 27 28 29 Period 4 Ge As Se Br Kr X .Ge Sc. Ti NT , Cr Ma Fe Co Ni Cu zji Ga

50 51 52 83 54 37 38 39 48 41 42 43 44 AS 46 47 48 49 Sb Te 1 Xe Period 5 Rb sc I, zr Nb mo (Tc) Rs Rh Pd Ag Cd In SS 4 . ..

67-71 - 81 82 83 84 85 86 72 71, 74 175 76 78 79 80 55 56'Lantha- TI Pb Bi Po At Rn Period 6 W Re Os Pt An Hg ( Cs Ba-aides Hf Ta

89-10 s - , - . .., . Peri°4 ;7 87 88. Acti- rt \ Fr: Ra aides `-' --, .4

Lanthanide 57 58 59 60 .. 61 62 63 64 65 66 674 68 69 70 } 71 Yb Lu Series La Ce pr Nd (Pm) Sm Eu Gd Tb CY Ho Er Tm .

97 98 98 100" 101 102 103 Actinide 89 90 91 92 93 94 95, 96 (Md).(--) (Lw) Series AC Th Pa U (M1)) (PO (Am) .(Cm) (13k) (CO (Es) (pm) 15 14' Figure 2.17 ELECTRON (llNN CAN& 0 PROTON Ihnithe Owns) NEOTNON 1N Paw) FIGURE 2.21.Elementary particles that make up an atom. distance by ELECTRONS which whirl around the nucleus at tremendous speeds. Electrons are very small and have practically no weight. 2.21If we examine the structure of the nucleus in greater &tail,we see that it consists of little individual balls of matter that are about the same size in all atoms. FIGURE 2.19a.If an atom were the size-of iheEm- Some of these little balls of matter havea pire State Building, its nucleus would beas large as a pea and the electrons would revolve around ,,poeitive electrical charge. Theseare called the nucleus at a distance of several hundredfeet. PROTONS. Others,, called NEUTRONS, (Understanding that there is so much unoccupied have no electrical charge andare said to space within the atom is important to an under- be electrically neutral. Botha proton and standing of the interaction of radiation withmat- ter.) a neutron are muili larger 'and heavier than an electron (see Figure 2.§1). - TRONS, PROTONS and NEUTRONS, the 2.22 For each posaively charged PRO- latter three comprising the basic atomic TON in the nucleus, there Isa negatively building blocks as shown in detail in Fig- charged electron in orbit around the nu-' ure.2.1913. cleus. The number of protons in thenu- ,2.20., The NUCLEUS is the heavy, , denie &ire of the atom, containing practically all of its weight. Aswe have seen, this nucleus is surrciunded- at quitesome

. . L HYDROGEN 2. HELIUM NDSHT OR RELATIVE RELATIvE . LINT SOMOLS MASS IN ATOMtC ELECTRICAL: LIAS UNITS * PIANO( Si Imams o OR I 007593 NIN * 4 I - Namara R 0. el I 0011911 saw 0

4 COI t CR ELECTRON 0 000549 Now I .113 OR

* AN ATOMIC MASS INNT (ov) IS EWA/ TO I II10'24 CRAMS OR ONE siLissTs Of A OILLYONTH OF A MILLIONTH Of A GRAM 3. unwell 4. BERYLLIUM FIGURE 2.22bomparing the atoms of the first four FIGURE 219b.Atomic building blocks. elements. _Olgus, therefore, aeterniines the humber of --electrotts which are in Orbit arOund the, nucleus. The: riu.raer of protons also deter- .- 'mines thenature of the element. Forexam- -*le; the sinee -positive Chargeon' the hydrogen nucleus balances ,the negative- _charge _ on-the electron. Thus, in its normal -or LJNEXcittpcstate, Me hydrogen atoth . aswhdleitrelectiically neutral. Thenext, element heavier -than hydrogen:is h'elhtm,

and it .has two electrons thatmove in; a *AEC 0114i 0.142 single orbit. Two positive charges in 'the 0 motor (Noki.; combo helium nucleus counterbalance thenega- faunae tft awns) tive effect of the two electrons. Lithium, 'F1duRE.2.23.The oxygen atom. the next heavier element, has three electrons. Only twq of these travel in the the drawing. One way to think of the six comparatively small area near the nu-V.,ter electrons, all revolving and spin- cletis, theIhird has a much larger orbit. ning, is as if they were tracing a hollow The lithium nucleus, therefore,has 'three shell like an ultra-light tennis ball. Scien- positive charges. See Figure2.22 for exam- tists customarily' speak of electrons as ._ ples. being located in SHELLS, classifiedas K, 2.23If time and space permitted, the L, M, N, 0, P, A, and sub-shells, in accord- atoMs of all the eIementa coUld be_exam- ance with their energy level, which is Pro-

_ ined one by one. For presentpurposes, portional to a distance from the nucleus. hoviever, the oxygén atom (Figure 2.23) 2.26 Continuing with our detailed look will be an adequate example. at the oxygen atom, we see that in addi- 2.24 The oxygen atom has eightpro- tion to the eight protons, and the two ,Ions, and therefore eight positive charges shells with a total Of eight eleltrons, there in its nucleus. To balance these eight pOsi- are also eight uncharged particles or neu- l'tive cg;ges, eight -electrons Are required. tron,. -The first two, electrIms are inthe hiner 2.26 With the single.exception of hydro- ' Orbit, as" is normal in any atom abbve gen in its simplest form, all atomic nuclei hydrogen. Three eider orbits, containthe contain neutrons as well as protons. The Other three.pairs ofelec*ons,as -shown in lighter elements tend to have appro*

FIGURE2.24.Another way of Viewing the apm Jiu'aminite solitlsystem. Instead of the sun at the center, ihere itthe nUcleuisrinstead Of the Pianets inorbit;1/4there are tht electrons. mately equal quotas of neutrons and protons; the heavier elements have more neutrons than protons. This fact, to be explained in greater detail later, iriiiipor- tant to tim understanding of.radiation.

ISOTOPES HYDROGEN DEUTERIUM COMMON ' RARE 2.27/The number of neutrons in. the STABLE FORM .STAILE FORM -nucleus may range from zero to almo'st 150. In certain elements it is found that different atoms of the same element have the same number of protons but vary in the number of neutrons. To the chemist, this is of little concern because the chemist works with the orbital electrons, and since all of these atoms have the same numberof protons,, they will have the same number of electrons in orbit. Since TRITIUM RARE they have a different number of neutrons RADIOACTIVE FORM in the nucleus, however, the various atoms of the same element will not all weigh the FIGURE 2.29.Thotopes of the element hydrogen. same. MASS.---A measure of the quantity ,oftritium contains one proton and tWo neutrons in its. nucleus. The addition of the matter . second neutron to the nucleus produces an WEIGHT.A measure of 'the force with dnbalance in the proton to neutron ratio .er. which matter is attracted- tothereby causing an unstable or excited the earth condition due to the exCess energy. Thik 2.28To. fhe nuclear physicist and physi-, excess energy iseinitted in the form of cal _chemist, these are different forms ofradiation. Tritium is the. only isotope of thp same chemical element .differing only hydrogen that is radioactive. in the number of neutrons in the nucleus. 2.31Onry three isotoPekofthe element Many of the isotopes are stable. Some ofhydrogen exist. Attempts to produce a the isetopes are Unstable Mid therefore fourth igotope fail because the nucleus of a radioactive: tritium atoni will 'not capture an add- 2,29 Figuxe 2.29'shows various isotopestiOnal neutron. Of the eleMent hydrogen. Theteavier iso- 2.32 Figure 2.32 shows- two different, topes Make up a very small fraction of oneisotopesof uranium. Oneis called uranium perCent of the total amoimt Of hydrogen 288. Its nucleus contains 92 protons and found ii nature Ordinary water consista 146 neutrons which cernbined total 238. ' of Molecule's each Of Which is, made up of Particles. The other, uranium 235, con- tWo attans of hydrogen and' one atom oftains 92 protons and 143 neutrona which oxygen. If -Water cOntaint hydrogen, Whichtotal 235 particles-Both of these will react is-not the wrmal iSotope ofhydiOgen (one chemieall.y in exactly the same way, proton) but .the deuterinm isatorie (one Therefore, te the chemist they are the, Proton'and brie neutron) it Will took like same. the important difference to the nu-.). "regular water, taste like regular water,Flear Physicist is the fact that, although and, froni the: Ole-Mica point of view, it both are xadioactive, the_ 1i235 will sustain Will be `water. however, frOM a nuClear.. a chain reaction whereas the V" will not,., point Of'irieur, this Is HtAVY WATtit 2,38As. previously stated, the first ele- ..because. it is made, With, the heavier iso- ment, hydrogen, has:only threeisotopes in OthydrOgen. its ftaMily. The number of isotoPes for. each 2:30 The third form of hydrogen.ealled of the other elements varies ,considerably .11 with, foreXample, as mink as 25 istotopes -=' for-the- fiftieth.element, tin. 2.34 Altogether thereare over 1,200 ilsotopes,,the majority of which are radioactive. Most elements have twoor more isatOpes.:While the number of neutrons in the nUcleus does. not _materially 'affect chemical:behavior, the neutron- to proton (n:p) ratio-Of the nucleus does affect The atom in other ways. FIGURE 2.39a.Atoms of the element hydrogen and the element helium.

We are close-to our main objective- -understanding nuclear radiation!!!

2.35 Before the. diicovery of the'neutron, scientists identified any element by a one-letter or two-letter .symbol representing its chemical nameH for hydrogen,' Cl for chlorine, Na for sodium (whose latin- ized technical name is natrium, hence the Na), and so on. The nuclear physicist accepts these time-honored letter symbols; but when speaking in general terms, he refers to any of them as SYMBOL X.

URANIUM23,5 `-RADIOACTNE 2.36- To make precise reference to a given atom, the nuclear physicist (1) pie- cedes symbol X with a numerical subscript calk" SYMBOL Z and (2) follows symbol X with a number (often, but not always, written-ad a sziperscript) called SYMBOL A. His identification of an atom, then, takes the form z)E., or sometimes when Z is clearly understood, simply'XAorA. For example, 17235 and tU238.

2.37 SYMBOL Z.-,-The subscript Z is called the ATOMIC NUMBER; it tells how many prOtons 'Pie nucleus contains (ahd simultaneonsly, of course how many pla- netarY electrons the atom has in it's normal state). For hydrogen Zis 1; for oxygen it'is 8; for uranium itis 92.

. 2.38 SYMBOL A.The final identifying symbol is an ATOMIC MASS NUMBER URANIUMPO 4. RADIOACTIVE- , . , . . -representing the sum of the protons, and i?1,OURp2.3.2.=-: LiOtoki-of #e elementuraniuni. the neutrons. :1.9. <

protons being positively charged tend to PRO- ATOMIC NEU- ELEC- SUBSTANCE SYMBOL TONS MASS TRONSTRONS repel each other. The repulsive force is (Z) M.IMBER' (A-Z) (Z) ) (A) counteracted, however, by a nuclear at- tractive force called Binding Energy. Very HYDROGEN _MI I. I 0 i 1 \. little is known of this energy. However, it DEUTERIUM' is known that for elements which have 2 1 1 1112 OR 102 ' I TRITIUM relatively low atomic weights, nuclear sta- 1 3 , 043 OR ITS 2 bility occurs when the number of protons OXYGEN and neutrons are nearly equal. Heavier .906 16 8 8 , elements, those with higher Z numbers, URANIUM 92u238 92 231 require a higher neutron to Proton (n:p) 146 92 ratio for stability. Whereas those elements FIGURE 2439b.Symbol meanings. in the lower part of the periodie table (Figure 2.17). are stable when the isotoPe IMPoRTANT has an n:p ratio of,approximately one (approximately the same number of neutrons To find the number of neutrons in any as protons). The n:p ratio must increase as fully identified atom, subtract Z from the Z number increases if the stability of A. the atom is to be maintained. Beginning vrith the element bismuth, atomic number 2.39 Let us see a few examples of the 83, when the n:p ratio increases above uses of these symbols. In Figure 2.39a, we 1.5:1 there aie to stable isotopes. The sta- see an atom of hydrogen with the sub- ble range of n:p ratios for many elements script 1 as its atomic number (Z), since is not critical, i.e., there are several ele- hydrogen has only ,one proton, andsuper- ments with many stable isotopes. script 1 as its atomic mass number (A), since the atom contains only theone pra- 2.41lin unstableatom, one with a n:p ton and no neUtrons. The Z number for ratio 'either too high or too low, willeven- helium is two, since it has two protons in tually achieve stability by spontaneous the nucleus. As we haveseen, each ele- emission of energy and/or particles from ment has a distinctive atomic numberrep- its nucleus. This process is knownas RA- resenting the number of protons' in the DIOACTIVITY. It may be the natural de-: nucleus, and we can determine thenum:. cay of unstable isotopes Which occur in `ber of neutronain the nucleus by subtract- nature or it may be das the result of artifi- ing the atomic number Z from the atomic cial radioactivity which has been caused mass number A. As examples, the nucleus by man. In,each case the nticleus is inan of 92U23s contains 146 neutrons arid the unstable or excited state, having anexcess nucleus of2;C" contains 32 neutrons. Since of energy which will 6elradiated allowing novinal atoms are electrically neutral,each the nucleus to achieve a stableor ground atdm will have tliesame number of elec- state. trons as there are protons in theenucleus, i.e.,the Z numherMll equal the number of RADIOACTIVITYis the spontaneous disinte- protons in the nucleusor the number of gration of unstable nuclei with theyesult- electrons in orbit abourthe nucleus.The ing emission of nuclear radiation. 'subscript Z number is sometime*disregarded because the atoni is identified1337 2.42Radiation is the conveyance.of 'en: Chemical symhol. Thus Hes,or 2Het both ergy through space. Everyone is familiar' have the same meaning. Figure2.39b with the radiatioo heat from stoves, shOWshow symbols are interpreted. ' light from plettric lingits and thesun, and 40/ the fact *that some kind ofenergy is' re- 2.40- The ratio of neutrons to protons Ceived by our radio and television sets to 'within the nucleus of the atom largely make them 'Otierate. The radiation of en- determines the stabilitY of the atom. The orgy from radioactive materials is Compa- A

41,

X FREQUENCY ARERELATED BYlc WAVELENGTH AND UNIT OF WAVES ANGSTROM UNIT -A PHYSICAL OF ELECTROMAGNETIC c = VELOCITY SECOND LENGTH, EQUAL TOt/210P CENTIMETERS; CENTIMETERS PER =3 x.ION SECOND, THE' AMOUNT Of ENERGY VIBRATIONS PER ELECTRON VOLT - =CYCLES/SEC. = ELECTRON FALLING THROUGH 1.? -FREQUENCY ACQUIRED _BY-AN CENTIMETERS OIFFERENCE OF ONEImo% X = WAVELENGTHIN A POTENTIAL. IS RELATED. TOTHE' LIMITS ELECTRON VOLTAGE (V) VISIBLE SPECTRUM .87000ANGSTROMS RADIATION (X), IN , - - 4,000 ANGSTROMS 14 CYCLES/SEC. WAVELENGTH OF THUS 1 3.7. x 10 UNITS, APPROXIMATE,LY 14 ANGSTROM 7.5x 10 CYuLES/SEC.r V = 12420/X ,

10-4 le lei 10-110-2 10-3 ,102 10 1 t I0 5 1 iO 104 e 1014 ipa5012 1011i010-10 100 I .1 i(VAVELENGTH X lot? wit ,4)15 I 1 I lite I1023 ANGSTROM UNLTS ohs. 1() CYCLES/SEC. 106 CYCLES/SEC. c'tcLgs/sre- CYCLES/SEC. CYCLES/SEC COSMIC , INFRA 1 GAMMA ELECTRIC RED POWER; ULTRA HERTZIAN ,V CILET (ODIC,/ TELEVISION,RADAR) VISIBLE X RAYS INDUCTION.' HEATING I r 105 106107 10 I 10 102 I 16-4 10-310j2 ENERGY wiz ics" 10 IY10 7 10 e 10-6 10 ELECTRON vou-s 2.42,Ele4trornagnetic sprIctrum., FIGURE 21 IC

or' ik

rable.to theie familiar forms of radiation ION. The two, particles, the- positiveion 'but, as indicated by Figure2.42, ere gener- (atOrn 6- atoms) and the negative ion(dis- ally higher in frequency and,therefore, Lodged electron). are knownas an ION represent greater energies. .PAIR. The prikess which caused thissepa- ratia of particlesmakingup the atom and the attendant electrical Unbalanceis NOTE known as IONIZATION. Remerabedioactivity isa PROC- ESS/N-uclear radiation is the PROD- UCT of this process. 2.43 Moms in the unbalancedstate described in paragraph 2.41are said ,to be NEUT/tai. UPI RADIOACTIVE. Theyare spontanemisly emitting some type of IONIZING radiation energy. IONIZATION is11 process which results in the formationof electrically charged particles (IONS)from neutral atoms or ,molecules.

. 2.44 For a closer look at ionization:cOn- sider Figure 2.44 in which_a normal atom bjected to a bombardment of-energy. FiGu4 444 oni z ati on. 1 The energy of this bombardmentmay knock an electron from its orbitinto free 2.45 Nuclear radiationsare given off by space, i.e., it will not be associated with atomsorhich have more than the normal a-hi-atom. It is a negatively chargedparti- complement of energY. The physicist cle in spade and is referred says to as a NEGA- theyare 'UNSTABLE. This unstablecon- TIVE ION. The remainder Of theatom dition is often caused by too lowor too from which the electronwas dislodged is high an n:p ratio at explainedearlier. also electricall3i unbalanced bythis event. Radioactive 'atoms literally erupt from Hiving lost one electronwith its negative time to time emittingenergy from the charge, it now has an effectivenet positive nueleus. Thele nuclear radiation emis- charge df one since itnow contains one sions are classified as ALPHA PARTI- proton for Which there is no. counterbal- CLES, BETA LIARTICLEA and GAMMA* ancing 4dectron. The positively charged RAYS.'Each tyfrg of radiation will be dis- atom (or atoms) is knownas a POSITIVE cussed in ,more detail in later paragraphs;

(ZI C 5.2 + 01 ,---- 27 CO° + loons#3 RAMATIC*1) , . # - I"- ' . ''' FIGURi 2.47.the normil atom of Co" bombarded by a'neutron.In this case, the atom accepts this neutron in its nucleUs, the A numbeivincreases by one to Co" and the,atom M radioactive. , 2,46 Nuclear radiation differs from 100 '1200 mc other forms of radiation in the sense that thi nucleua of ari unstable atom contains -an, excess of energy which will be eniittear regardless of 'man's efforts. Use of heat, . chemicala or Kessure will not stop or alter 50 NO0MC the rate of nuclear radiation emissions \ from a radioactive atom. Man can cause or I \ stop other:types-of radiation such as heat, 4 \ light, or even other atomic -radiations uw 25 1.5° ss IN 7 NALF`LWE PERIOOS THE RADIATIONLEVEL LI which in .many ways Compare to nuclear o. LESSTHAN I%0F ITS ORIGINAL INTENSITY 'radiation. ,In the case of heat and light 12.5 '1;25 12.5 radiations caused by electricity, merely 6.25 156 flipping a switch can start or stop these HOURS. 24 48 72 90 120 144 168 radiations. DAYS I 2 3 4 5 6 7 2.47 Many nuclear radiations are FIGURE 2.49.--Decay curve. caused by bombarding atoms with energy, causing them to radiate energy which up to millions of years. The following ra- ceases Nyhenever the bombardment stops. dioactive eIenients demonstrate this wide However, if the atoms_in the Material be- range of half-lives;-argon 41,109 minutes; come radioactive as a result of the bom- iodine 131, 8 days; radium 226, 1,620 years; bardment; they will then spontaneously plutonium 239, 24,000 'years. Figure '2.49 einit ionizing radiation of one or more depicts a gamma emitting material with a types until they reach a stable condition. 24-hour half-life. This material when first One of the sources of nuclear radiation made,radioactive has a quantity of radio- commonly encountered in radiological de- activity of,200 Millicuries. In 24 hours the fense training is27Co6°(Cobalt 60). Figure 'radioactivity would be down to 100 millicu- 2.47 shows how this isotope_ of Cobalt is ries; in another 24 houa it would be down developed from27Co59. to 50; in another 24 }tours it would bse down to 25, etc. 2.48, Different radioactive elements vary greatly in the frequency with, which their:atoms erupt. Some radioactive mate-. PROTACTINIUM 'Hale in ,which 'there are only' infreqpent ,einisSions :Or radiations tend to have a <- ; I. yery long life 'white thosewhich are very C". active, radiating' frequently, may have a comparatively sholk life. The time differ- ehee is Very great between, short and long

, AhER radioactive materials.. Some sub% 34,000 starices. may stabilize themselves in a YEARS,1 smalr part of a 4econd, while a radioactive isotope With 'a long life may chanke or decaY only, slightly in tbouSands 6r inir- rioif Years, Th'e rate of radioactive de- I cay- Measured in HALP,LIFE, ttl'e tiniarequired for the radioactivity of a given athount of a particu1ar-rnater4 to AFTER 34,000 , AFTER decreasa,to half its.original value: MORE YEARS- 34,000 MORE YEARS ,. P, ,249. ,Thkhalf-life of a, radioactive-mate-.

ria may range_ rom, fractions ota second FIGURE-2.50.Another view of half-life. 23 2.50 Let us look at another exaMple. its original activity, and in10 half-lives -Assume that the block shown at theupper the activity will be down to lessthan 0.1 left in Figure 2.50 is composed entirely of percent. The shorter the half-life, themore the radioactive protactinium isotoPe highLy radioactive the materialwill be. known as Pa231. The half-lif,e of this particular isotope is 34,000 years. At the end of 2.56 As we will 34,000 years, therefore, half of the original see in more detail .in suhnquent chapters, half-lifehas impor- protactinium atoms will have undergonetant bearings on safety. It is obvious, first transmutation to other elements. The rest of all, that any isotope witha long half-life will still be protactinium. If theywere is potentially dangerous if it is producedin separated from the transmutedatoms, the large amounts. When, such protactinium atoms would now constitute an isotope is the secorld block in Figure 2.50. once formedwhether by nature or inan atomic power plantor (Juring a nuclear 2.51 The second block will not decay explosionit will contaminate itssur- completely in the second .34,000 yearpe- roundings for a long time tocome. riod. Unquestionably, it has only halfas many atoms as the original block; but by -2.57 For some of the artificially that very fact it offers only half the origi- pro- duced radioactive isotopes, thehalf-life is nal opportunity for atoMic reactions to measured in hours, minutes, take place. As before, half.of the atoms (a or even sr- onds. These isotopes are extremelyactive; quarter of the original protactinium at-, that is why they decay so fast. oms) will remain unchanged at the end of the second half-life. 2.52 During the third half-life, the COMMON TYPES OF NUCLgAR number of protactinium atOms will again RADIATION be cut in halfand soon. In general 2.58 There are threecommon types of 'terms, then "x" grams of any radioactive nuclear radiation *with which isotope will decay in accordance with the you must become familiar: ALPHA and EETAPAR- 'following series: TICLES, and GAMMA RAYS.

1 x 2.59 Alpha Radiations emittedby ra- 2124+;+;c6-1-L-F6x4+1; 56c84-21 dioactive materialsare often called alpha 2.53 No matter how far thisseries is radiation or simply alpha. Alphaparticles extended, its final term, x/n willrepresent are comparatiyely large, heavy particles of .only half of the protactiniumatoms that matter which have been ejectedfrom the were intact at the beginning of the given nucleus of a radioactiNte material with half-life. If x/n atoms havebeen lost dur- very high velocity. The velocity with ing the preceding half-lifethrough decay, which these particles leavethe nucletis an equal number still remain to startthe determines the distance (range)that theyo next half-life. will travel in any substance.As indicated in Figure 2.59, an alpha particlecarries a 2.54In other words, thesum of this net positive electrical charge oftwo and series approaches an atomic mass of 4.00277. Thus the alpha x, the original number particle is equal to the nucleus of of atoms, but (in theoryat least) never a helium atom which contains twoprotons (with one, quite reaches it. There isalnays a frac-^ positive 'charge each) and tion, equal to x/n, representing theatoms two neutrons. that are still intact. . However, when we compare the speed of alpha to that of beta andgamma, we find 4.C this to be a relatively slow 2.55 A useful rule of thumb rate as- might is that the be expected due to:alpha's sheand weight, passage of 7 half-lives will reduce thera- Alpha rays are literally smallpieces of dioactivity to,a little lessthan 1 percent of matter traveling throughspace at speeds 24 17 . . of 2,000 to 20,000 miles per second. When a 2.62The, neutron is another type of ra- radioactive atom decays byemitting an diation which 'accompanies certain types alpha particle, transmutation of.this atom Of nuclear reactions but is not 'encoun- to an atom of lower atomic number (Z) and tered in natural radioactive decay. As was lower atomic mass number (A) occurs. discussed preyiously, this type radiation is

"O"C ILICTIIK L .441.0*. Si.f0C..1 ....f 0411 Ci./4,2 RIU41.1 A DCW.C.I. 10 KM.. 4.14. SC P411741.1 00121 +2 .0. 11.00110 C0' MI CLIC1C41 V. C141.Os 10 ...1... 6-- KUA 01.4.01.2 0000141 . VICO CLIC1.10M 0 11.1004104..2 vv." 76;v1-4 00111 MY( mu u.11411 01 (MOO

FIGURE 2.59,--Characteristics of nuclear radiation. , 2.60 Bela Particles are :identical to highspeed electrons. They carry a negative electrical charge of one and are extremely light, traveling at.speeds nearly equal to the sp'eed of light,18000 miles per second. Although theatomiC nucleus does not contain free electrons, only protons and neutrons, the electrons which are, emitted as beta particles result from the spontaneous conversion of a neutroninto a proton and an electron.The neutron which lost or emitted-the betaparticle has become a 'proton with a positive charge and thus-the atom has been ch nged. Transmutation has produced an atorn with

a_higher Z number. \. 2.61 Gamma Rays are a type of elec- trornagnetic radiation- which travel\with the speed of light. As indicated inFigure 2.59,, they have no measurable masS or electrical charge. We have be-come ac us- tomed to.the use of X-rays in the med cal field. X-rays and gamma rays are simi ,ar, j. , but there aretwo important differenees betWeeh them. First, as indicated in.Fw- ure 2.42, while there iS someoverlapping, gamma rays are generally of a high r freiluency. The basic difference, howeve is theft. source. "GaMma rays originate i the nucleua while 2C2rctys originate inot clpud of electrons about the nucleui. The emission of an alpha or beta particle from thinucleus of an atom.as shown in Figure 2.61, almoSt invariably leaves the nucleus with an excess 'Of -energy (excited stath) and Will be 'accompanied by the emission of -, g9nima rays toreach ground or stable condition. FIGURE 2.61,Excited to stable nucleus. 25 A able to iiiduce radioactivity in stable iso- units; and since the number.of protons has topesk been-changed, it is no longer uranium but is, in fact, thorium 234. RADIOACTIVE DECAY AH'D DAUGHTER 2.65b Thorium 234 emits not an alpha PRODUCTS-000"r particle brit a beta particle. Where does , the beta particle come from? Remember 2.63Radioactive detay, oiten results in that a neutrOrl is electrically ,neutral. We "transmutations", i.e., the Change of one have seen that an electrically neutral element into anOtherand the dream of the state can be reached when positive and inedieval alchemists. Some radioisotopes negative charges balance one another and decaylthrectly toa stable state in one that a neutron can act like a.proton with transmutation. Others decay through a an electrpn tightly tied onto it as shown in series of transmutations or steps formingFigure 2.85b. different radioactive elements called . , DAUGHTER PRODUCTS before finally 2.65c The n'egative charge of the elec- reaching a stable state. tron balances the posItive charge of the 2.64 proton resulting in a neutron. When. this Consider now What happens when negatively charge eleGtron is\ ejectedas a a radioactive isotope emits radiation, and beta particle titie remainder 'is no longer follow one atom of uranium through its electrically neutral, but.now has a.positivi successive transmutations: Starting with.charge, thus changing a neutron gt,a pro- an .atom of uranium 238r-w,rtich. has 92 ton.. In effect, one proton has been gained protons and 146 neutrons, follow the.and one ne tron has been lost, Now there transmuttttions in Figuie 2.64. are 91 ptons and 143 -ne,utrons, The 2.65aUraniumt2g8-emitsan alpha par- weight istill 234, but since the number of ticle. An afpha particle consistpf twp prOtons h a been 'changed, the nature of protiins and two neutrons, and therefore is'the e nt has been changed and. is now an iitgynic' nucjeus in its own right. It is an atom of prOtactinium 234. the ntcleus of the helium atom. (Helium 2.65dProtactinium 234 also emits a -has a nucleus composed of two protons and beta particle so 1 proton is added, and 1 twO neutrons; With the alpha 'particle neutron is subtracted;leaving 92 Proton# emitted, there are now 90 protons tnd 144 ,ineutrons. The nucleus now weighs 234 and 142 neutrons. Its weight is 234, but 4. the element is, of course, again uranium because it now has 92 protons. ELEMENT ANO TYPE OF NUMBER OF ATOMIC WEIGHT RADIATION VATTED PROTONSNEUTRONS 2.65e Uranium 2344em1ts an alpha par- URAMUM- 231 92' I46 ALPHA PARTICLE -2 -2 tide, 2 neutrons and 2 protons are sub-- THORIUM-234 DO 144 tracted, leaving 230 particles in the nu- SETA PARTICLE +I PROTAC1'INIUM-234 91 143 'cleus. Since the number of protonsis. back ETA PARTICLE +I .1 IMMS/16234 92 142 'to 90, the element is now thorium 2-8-0. , ALPHA PARTICLE THORIUM-230 30 140 2.65f Thorium 230 emit,s an alpha Parti- ALPHA PARTICLE -2 -2 pnle. Subtract 2 protons and 2 neutrons. It RADIUM-2 26 ' ,', os 136 ALPHA PARTICLE -2 -2 ow haa,a....weight of 226, and since it has RADON-222 SW 136 ALPHA PART -2 POLOMLMI2111 64 134 .ALPFIA PARMA -2 -2 LEAD.414: 112 in 132 SETA .PARTICLE +1 -1 1111106./711-214 63 IM sir . BETA PARTICLE +I -1 476411UM-214 114 130- ALPHA PARTICLE 42 -2 LEAD-210 112 126 SETA PARTICL +I -I INSMUTH-210 113 , 127 'SETA PARTIC E +I 7 ^.1 110 POLOMVOA210-' ' 114 126 -1111 , C ALPHA PAR E

LEAD-206 STABLE 016 92 124 -

FIGUREU5b,--Concept of a neutron changing intoa FIGURE 2.64,The decay chain ilftwuranium atom. proton by a beta particle.

r) ft .19 s) only 88 protons in the .nucleus, it is the does not take with it all of the energy that elementradium. the, atom would like to get rid of in this 2.65g Radium emits an alpha particle, particular disintegration, it throws off 802 neutrons and 2 protpritare lost leav- some of the energy in the form of gamma ing 86 protons and 136 neutrons. Our ele- radiation. Therefore gamma radiation can ment is now radon 222 which is a gas. be given off by many radioactive materials 2.6511 Radon 222 emits .an alpha parti- in addition to.the beta or alpha radiation. cle, leaving 84 protons altd 134 neutrons. 2.67 The foregoing makes it clear why 4gain a different element is formedpo- gamma radiation occurs and can therefore ronium 218. be detected from a radium dial wrist watch'or from uranium. ore by g prospec- 2:65i Polonium emits an alpha particle, tdr. Both radium and uranium are pure 'which leaves 82 protons and 132 neutrons, alpha emitters, but as time passes the and is lead 214. decay process goes on andlorms daughter 2.65jLead 214 emits-a betwi.particle products in the radium and uranium. It is which increases the numbeatikotOns-by from the decay of these various radioac- 1 and decreases the_ number 'otrieutrons, tive "daughter products".that the gamma by 1, leaving 83 protons arid 131neutrons. radiation is given off. Pure radium or ura- This forms bismuth 214. nium, freshly prepared, represents only an 2.65k Bismuth 214 emits a beta particle alpha hazard and could safely be handled which adds 1 proton and subtracts 1 neu-, with the bare hands as far as external tron, leaving 84 protons and 130 neutrons. hazard is concerned. (Handling it with the 'this is polonium, 214. bare hands is, not a good-idea because of 2.651 Polonium 214 emits an alpha par- the possibility of introducing some radium ticle which takes away 2 neutrons and 2 into the body by thirineans and, besides, protons, leaving 82 protons and 128 neu- heavy metals are toxic.) After the passage

, trons for a mass of 210, and the element is of time, however, the daughter products 'lead 210. start to build up and alpha, beta,' and gamma radiation are. all being given off -2.65thLead 210 emits a bet article, 1 frOm the sadiuni and its associated daugh- leaving 83 protons and ,neutrons, which now becomes bismuth 210. ters. 2.65n Bismuth 210 emits a beta particle which adds a proton and subtracts a neu- INTERACTION OP RADIATION WITH tron, leaving 84 protons and 126. neutrons. MATTER This is polonium 210. 2.65o Polonium 210 emits an alpha, NOTE which leaves 82 protons arid 124 neutrons. The important thing to remember The total weight is 2,06; the element is lead about nuclear radiation is that it is a 206. "shooting out" of particles or 6its-of energy, some large, some smail; some 2.65p Lead 206 is stable and not radio- fast, some slow; some weak, vd-me pow- actiye, therefore; this is "the end of the erful. Since everything contains at- line". omsincluding our bones, skin, and Well, that's fine, and all very inter- organs, of coursethese particles 2.66 strike the atom's with force, the amount esting, and accounts for beta and alpha depending on the kind ofparticle, and radiation, but what about gamma radia- gther factors. Actually, since the atom tion? Where does that come fromZ As we is, as, wehave seen, made up of an saw. in paragraph 2.61, gamma 'radiation extremely compact core and shells of electron( 8), these electrons, bear' the originates when, the discharge of qne of biunt of the hammering given out 'Mega particles frOM-a-nucleuirdoes-not when the atom is struck .by particles. take 'sufficient energy along with it to As will be seen, the elect/iv= feact-to-- leave the nucleus: in quite a contented this hammering in various ways. This -state. If the particle leaving the nuéleus has great significance to the study of 27 , radi4tion safety and the effectsof radiation -On the- boay,as you will. dis- coter-later. 2.68 Alitha particles lose. theirenergy *rapidly- and hende havea limited renge, onliabout 6 or 7 centiMetersin air, and' are tompletely stopped by a sheet ofpa- per.-Vien the alpha particle is storiped, -stabiliied, or reaches ground State,it has 4iicketup tWe electronswhich are- availa- .1le in, spaCe thua makingit:a neutral he- Thetas-of energy by the alpha- paricli as it. traversesspace is due, to its nary&ION high diecific ionitation, i,e., the numberof ion pairs produced FIGURE 2.69.--Excitation and ionization by an alpha per tentimeter of path. particle. Each ionization -event in airrequires about 32-36 ELECTRON VOLTS,per ion is a greater probability of ionizing -them. pairproduced. The unit electron volt is the With this loss of energy there isa reduc- amonnt of energy acquired bya unit tion in speed and hencea steadily increas- charge 'of electricity when thecharge ing amount of ionization, at first slowlyi. moves throiigh _a potential difference of and, then more rapidly, reaching.a maxi? 'one volt. For Otample, ifan electrOn mum and then dropping sharply almost to Should start at a iiotential ofzero; Volts zero. Figure 2.70: is a representativecurve and be aCcelerated toa point baying a for the. specific_ionization of alphaparti- Stet-Alai uf 32 vOlts; it wonldadoire an cles. The range andspecific ionizationvar...., energy egiziyalentto 32 elect*. volts. An ies.somewhat for different radioactiveiso- elettron volt iaa very sinall amount of topes due to Variation in theenergy mith energy'. gore cominkternisarethousand which the alafit .particle is .ejected, 4.0. electrini. Volta (ket,. arid million'electron MeV'tolOOtteV. however, allalphaparti- =- clei:ethitteit** siiieCific nuclear reactien , have esaefitially-the same energy, aridso 2.60 'The high specific ioniiation-of (al- _ _ pha pailicles; 'go;00040,000-loir-pairs the:saMerange, , , . per ntiMeter of air traversed, is.due to.sv- 2.71 !The beta pattiele iioeatot loge -its er,l. fROOTRI, .tirst, alpha iSs-arelatiVely energy _as rapidly as tile alpha partic* Jirge liarticle and hasa high- 1;,ositive This is due te the, laCtthat it isa, very chariot tience ft Will not onlytollide4th small parade fiasjesf Charge tlian the h*tqr, but there will talitcjnent "(qtrQ4atio,.intata4finrii*itb,ijie-;elee- which 0i0-4-pasOng.'1:4ese..inter- 4ietiOna.4einit.*:**:10g,z0;enetgY ,electron- frOin jtsurbit 4000 (ioniOition); or it may lose Unerig to' the V 3 atothliy:Merely,displaeing _electrons Irpm -their tiOrinat!:Orbiia ejecting Wei& a 2000 :tr.* 1116,-aioni-,(eXeitatipn),figAre_ 4:09'

isboWa;'tba:4fiteten00"-lietWeezi:' an,lexcited 1000 -E,t0*akitia,4YOsitive!ieh..'" Or' Tit,additiOnt4being large2aruiposi- 3 tively -charyeit; -Okq, :aipna ,partiCle 4 ititoo orirAnct eoinParstiVel$c:slolc,,,,ifict-by-*egkaining -in bwitomictiAs1 -0**idnitY;;Citthe atoins, in its Pith, tbere 111:61.1itE 2.70.tpeclfie ionizationof alph&particlea, 28 '2 1, :alpha ,and.lS inoVing at a -higher "vane MOM** *TS MOS 1014a1011 ofsp ed: An-alpha:particle, because of

ts relatiVelY 'heavY weight,- is not easily , 2X0-20.03 20.1:00-90.0O3 efletted:and tendatotravel in a Straight ALM1 5-70. le Im*Uto 'tireittiSing:iyhigh degree of ionitation. A iftrAX bierticle.,, being light-Weight is easily ..- , bititiked -around in anY material'. There-- 1 25-21%. 30-5Co fox*, #11 range in terins Of diStance from ICU ZCO- 6:0 m YIP 0 r 1.04T. me oositm the =point -of origin ,te the point where it aisociatealfself With an atom may. - _,vary-considerabiy.,. _ The actual distance atat,4 IJSCOr WO- vuocema 5-I/ -trave1ed_by the beta particle also varies to MOMS 104.000 kV= a,censiderible extent-but notas- much as the Measurement from the pOint of origin :to-thepoint where Complete-49n of, excess FIGURE 2.74.Characteristics of nuclear radiation. energy occurs. Unlike alpha, the beta par- rapidly as either alpha or beta particles. ticlesemitted-by any given nucleus.have a Gamma rays or photoni produce no direct _range-of velocities and ,only mean,or maxi- ionization by collision as alpha and beta mum energies:can be assigned, to primary because gamma rays have no mass. They beta.particles. Tables almost invariably are absorbed or lose their energy by three ..ShOw Maximum energies. : processes known as the PHOTOELEC- The rangeof velocities for beta TRIC EFFECT, the COMPTON Etl*or, partteles-rangeS.from, about _25 to .99 per- and PATit PAODUCTIOg. -..ientOf , _thespeed of, _ light, with-correspond- 2.76 gamma .rays are higtfly penetrat- -ing .energy. variations. from, 0.626 keV to ing, their effective range depending on *y,' with a majority of them being in.their energy. The effect of aii on a gamma ray is so small that it is. not practical to the Vfeinity_, 'of, 1 MeV. The range of the ID beta partieleis proportional to its energy. measure the range of garnma radiation in Therefor:0,, -a 3 MeV beta particle will termls, of inches, feet, or ineters,,-but its traVeLfUrther than- a 1 MeV.beta particle. penetrating power is Measured in terms of _ 24 Range is only approximately in,. the amount Of material .that Will be re- Versely.proportional to ,the dmisity of the quired to reduce the gam* ray to some , -absorbing .inaterial-4hrough which it fraction of its original value. themoredense, the higher the 2.77 As ,a gamma ray or photon passes -number, the -More effective that mate- throUgh an atom it may transfer all of its l,will-beinstopping beta particles. How-, energy tO an, orbital electron ejecting, it beCaufie:,etthe emission- of X4ays when beta:partiCleS react -With, high Z ntirnber tilitotials, =to* Z,-riurnber "Itatis= aluMinum, glass-04--plastics -4reqlOrMallyiuised=asbeta'shields;, ^2 7'4 ,-.14.-sii'e ON; iceilizatiski:0,140tw par- iielea4S:apProxiMately10400iowpairs-per eentiineter VarYing,aacording tOrthe ., . , .energy-Ofithebeta44i,tijcle:and -the density ahiorbine;Material. the range of .beta. particlesIP air would b e -several ,me-, ThuS,, compared,to .the few-centime-, -tCr'-rarige of alpha ,i111,144., bete hitiia. long

*IA -/4amina.tays do.,*(-consitt of par- .!.4 v fY ., &E.:* no Mais, Oat* a( the speed of FIGURE 2.76,Pertetration4bisorption of nuclear ghnce'dlosee(refièrgy as' radiation.. frorwthe-atom. Tithe photon carriesmore ate gamma photons of approximately one- enerty than necessry toremove the elec- tenth to one MeV. tron.frem ita orbit, this-excessenergy can LOWER betransferredto the electron in the form ENERGY PROTON.

Ithietic' energy. Figure 2.77 shows elec- PHOTON ENERGY -refit- ejeCted jn this mariner. Theseare r;eferred joas PifoToELECTRONS, and -the process by whieh this tranifer ofen- .eigy was actoniplished is known as the 03kPTON .-PHOTOZILECTRIC-- EFFECT. Since the ELECTRON orbital electron In this case has completely absorbed the .energy of the gammaray, the Photon diSappears. The photoelectron will-ultimately lose its energy through the FIGURE 2.78.Absorption of gamma radiation by the formation of ion pair's. The, photoelectric Conipton effect. effect generally occurs with' lowenergy gamma photons of approximately one- 2.79 PAIR PROEFOCTION occurs only tenth MeV or less. with high-energy gamma rays. In this process, as the photon approaches the .nu-_ cleus of-the absorbing atom, it completely ELECTRON converts itself ineo a pair of electrons. One . PNOTON ENERGY of these is called a NEGATRON :but ad.- tuallyis an ordinary electron with a negative. charge. the other particle which has exactlyjthe seine mass as the negatron (electroa 'but carries. a .positive charge rather than anegatiVe-tharge is known-as a -POSITIWN arid. la deSignatpti by-the. syMbol e4-.. This proce'ss reqUires gamine , *rays with aininfinurn energy of 1.02-XeV, anthat-energy levels-above this the. ôSi bility-Ofthisinteraction increases. FigUre .FiGint!-2.77;=Absorptionof gamma kadiation by the 2.'79. -iaa. &Wain of thjs. reaction. . 1,4*(Mec3.*:01qct. . t Zia'cOMPTON'OFFF_CT.:does net. .'cohiP.10.05",.-40:sOkb, VS an 0.1tStof the gamMa ray.. A gatMhaTay iosoa, a part Of Ita-eriergY- to a free or,:4lOoseiy. houndor- INCIDENT PROTON. : -bitafeleetron hnt will Ootithi.1.16 aa.a scat- ,teret ganitinyOlietori jaflavi_er energi.:the eneryY ilf:-1.his-pitotiMICillf,e0al:,.the difference in. onginaL energy 1e88 .theianionnt .of e = ineryi-,tiranSferia't it the -electron. the. FIduga 2.79-AbsorPtion of gammkradiationby pair 40,iriunk ptp:ttb4 -reaCting--With--an-orbite electiOn;itat#44:itheu'gh it-had maSssinde 2.80E,nergy in 7e3idet4 of1.0z 14.17 is it dig/sea-the erketiOn to:be ejected- With share4 by the, negatron=positronpair in- high enere and- a lqWer 'energyphoton the form of kineticenergy., The positron rebefriidaat:sortle angle. Both 'the'election uSuallY,acquireS somewhatmore energy Which iSejeetedat ail angle-to thepath Of than the' riegatron. Thist-processJs. Often 'the origrnal gamma Photon and the loVer'Imert At* .an'ez«mpte. of Einstein's *ass- One* gamma photbri Whickit-arsoat- ertergy7theor1 {-E ne2, see;paragniph-2.5); an angle May tanse Vrther loni- since it is an exa ple rot*: the:Creationof *ion. Pignii 018, "sho-W's the, dompton matter .(t2lle pair o elecfrons),out ofpure -affect. -,Thlt eftect occurs with intermedil energy (the gamma ray)4thas been found -,` - that the mass of one electron is equal to therefore, is the an?: of Mat'isotope that 0.51 MeV. Since the pair production proc- wilkproauce 8.7 x101 nuclear disintegra- ess involves-the conversion of energy to a tion% per second.. Since the measure is négatron-positron pair, the energy re- based on number of disintegrations, the quire& must be at least two tiMes the weight of the radioisotope will vary from . energyequivalent of one electron, 0.51 that of radium. A curie of pure Co" would key. Any energy in the photon that is in weigh less than 0.9 milligrams, wpile a excess of 1-.02 MeV causes the ejected par- curie of U238 would. require over two metric ticles to have.greater kinetic energy. The tons. The curie is a relatively large unit. negitren is noW equal to the beta particle, .In training, a millicurie, niCi (one-thou- 4- - usually a very energetic' beta particle, and sanIth curie) and the microcurie, MCi Will react and .be stabilized in the same (one-millionth curie) are common units in manner as previouSly explained. The ,posi- use. At the opposite extreme, the curie is tron has an extireMely short life, which is too small. a unit for convenient measure- ended by cpmbining with an electron,. ment of the high-order activity produced However, before this happens it will cause by a nuclear explosion. For this purpose, , ionization, of other atoms. When' the posi- the megacurie (one million curies) is used. tron does join an electron thurcre-annihi- 2.83 The ROENTGEN (R) by definition

.lated With the production Of two gamma measures exposure to gamma and X-rays. photons of 0.51 MeV each, which eventu- It is an expression of the ability, of gamma ally will be absorbed by Compton or pho- or X-ray radiation to ionize air. One R will toelectric effect. proauce 2.083 x 109 ion pairs per cubic centimeter of air or 1.61 x 1012 ion pairs per Cuitt# AND-i0ENTGENS 'gram uf air. (See Par 4.13 for a more To. _be-:effective in your radiological complete discpssion.) defense Work, you muit geta frrm The curie measures radioactivity. grasp on the Ways Tadiation is nieas- . The roentgen measuresX or gamma - uredRadiation",,like "diatante" in a radiation. generat-,ccinCent. You- Would hive-a,' -AVealeiinderatanding:Of distance if you. Were -vagtie about- "foot.", "inth", -.REFERENCES "Mile"; "loilenieter", f`light year" and the, other .-4vaysy which distance is The Effects of Nuclear Weapons.Glas- _measured. The- same is true for radia, itone, SaMuel, 1964. PreparenDy the U. S. tien. . Department of Defense, 'and published by the U. S. Atomic Energy:Commission April 2.81 The CURIE(Ci) is the unit used to 1962; Revised Edition Reprinted February measure the activity of all radioactive sub- 1964. (For sale by Superintendent of Docu- stan'OeS.- It a measureMent of rate Of ments, U. S. Government Printiv Office,- ,.-decay or, nuclear disintegr4tion that oc- Washington, D.C. 20402. PricV4,00_, with, - curs-within-the ,radioaCtive material: The Curie: Thitially established the, activity calculator $4,00.) (that is, thedecay rate) of radium as the Explaining the Atom.Hecht, Selig, Ex,, --Otandard.-with which-the activity of any ,plorer Books Edition, Viking Press, Inc., 1964. othei-4.uhstariCe -was conipared. - Nuelear Radiation Physits.Lapp _242; By-usingAlormUla that, takes into account the ,number cif -atoms per -grain Ralph E. and Andrews; Howard L., Pren- and-the:Value .of the half4ife -in seconds, tice-Hall, Inc.; 1972. scientists ,have determined that the activ- 'Sedrcebook on Atomic Energy.Glas- stbne, Samuel, D. Van Nostrand Company, , ity of-radium-is:equal to37 x nuclear, clid*citration!s per:grant per setond..This Inc., 1967. valueisnaw.the standard unit of.corapari- Radiological Health Handbook.Pdblic .30n. A Curia Of .a*/ radioactive *tope, Health Service, Januaiy 1970. , . .

CHAPTER 3 4.

EFFECTS OF NUCLEARWEAPONS

After, our introduction to the language be said to have started with the explosion of nuclear physics, Weare ready to use of thetwo bombs over Japan in August, some of these terms in arriving at an 1945. understanding of a nuclear detonation and These, the first and only nuclear weaP- a knowlegN what can be expected from o s ever used against an enemy, caused a nuclear deto4ation. This is our primary itlprecedented casualties. Many of these objective arid in reachink it,we will also cover: asualties could have been.prevented if %b.- here had been sufficient warnings to per- WHAT is a chain reaction mit clearing the streets, and if the people WHEN doesit occur of Hiroshima and Nagasaki had -known what to expect and what to` do. For exam- . HOWis dlifce a chemical explosion ple, only 400 people out of a pdpulation of HOWis it different almost a quarter of a million were inside WHAT is fission and fusion the excellent tunnel shelters at Nagasaki_. that could well have protected 75,000 peo- HOW a nuclear weapon works ple. . WHAT aie the effects of a niiclear 3.3Information accumulated at Alamo- explosion gordo, Hiroshima, Nagasaki, Bikini, En- WHAT is fallout iewetok, and Nevada, as well, hs experience gained from other types of warfare,. has contributed to the store of defensive FAMILIARITY BREEDS CONTROL knowledge. From this knowledge, methods 3.1 ,During World War IImany large of coping with a nuclearweapon attack cities in England, Germany, and Japan have been, and are being devised. were subjecta;to terrific attacks by high- explosiye and incendiary bombs. Before NUCLEAR WEAPON DETONATION VS. the war, it was fully expected that such HIGH tXPLOSIVE DETONATION attacks would cause great panicamong the civilian residents of bombed cities. Ob- 3.4 The nuclear bomb was designedas servations during the attacks and subse- a blast weapon. Therefore, although im- quent detailed studies, ,however, fail to mensely more powerful, it resembles bear out this expectation. the studies bombs of.-thp-'-cOnventional type, insokras showed that when proper steps were taken.its destruttive effect is due mainly to the for the proteetion of the civilian popula- blast or shock that follows the detonation. tion and for the restoration of services However, nuclear detonationi do differ after the bombing, there was little, ifany, from'conventional -detonations in four im- evidence of panic. In fact,when such portant respects: measures are taken the studies showed Firsta fairly large amount of the that there was a definite decline in overt energy from a nuclear detonation is fear reactions as the air bombings contin- emitted as THERMAL RADIATION, ued, even when the raids become heavier generally referred to as LIGHT and and more destramilNe,_ HEAT; Secondthe explosion is accompanied 3.2 The history of nuclear defense rnq by highly-penetrating, harmful but IN- > 25 3 2 VISIBLE NUCLEAR. . RADIATIONS; tion, there is a rearrangement qf the at- Third7-!the nuclear reaction PROT:)- oms, and there is a change inthe charac- tICTS,. which remain after the detonater of the valence bowls. As stated above, tion, are- RADIOACTIVE,, emitting ra- a chemical explosive is-an unstable com- -iafions capabte of producing, harmful consequencesin liVing_organisms; pound, and in it the \valence forces are kourfhiluclear -explosions can be relatively weak. In the molecule's of the Many thonsands (or millions). of times decomposition products, however, the more powerful than the largest conven- same atoms are bound more strongly. It id - tienal_ _detonations.. a law of physics that the conversion of any , system in which the;constituents. are hey- '-,-IRINCIPLES.,:00A:CHEMICAL together hy weak forces intoine in'which

1.DETONATION . the forces are stronger, Must be accom- . panied by the release of energy. Conse- 0:5 Befóre the disdovery dhow nuclear quently, the decomposition of an unstable energy could-he Aeleased' for- destructive chemical explosive results in the libera- ptiposes, :the -explosive material in bombi tion of energy. Of the 'type in general, use, often referred _tO ',as conventional: bombs, consisted largely of atoms of the eleinents earbon, PRINCIPLES OF NUCLEAR DETONATIONS 'nitrogen, hydrogen, and okygen, in TNT 3.8 An atomic or nuclear explosion. re- -(trinitiotoluene) or of a related chemical sembles chemical explosions in the respect material. These explosive substances are that it is due to the rapid release of a large UnStahle mn nature, and are easil-k- broken amount of energy. But the difference lies , Mere-stable molecules. This proc- in the fact that in the nuclear explosion, essis asSOCiated 'with --the liberation of a the energy results from iearrangement relativel4large amount ,of energy, Mainly 'Wain the central portion, or nucleus of -Once the decomposition of a feW the atom, rather than among the atoms nthledules of Tiit-IS initiated, l3y means of themselves as in a chemical explosion. **likable detOnater, the muffing: shock Since-the forces existing between the pro- eaUseaStill More uiblectles to ;decompose. tons and neutrons inthe nucleua are iriuch Akaresult, the oVerall rate at Which TNT greater than 't'he forces between-the atoms '-MOlecules-hreak up is 'very -bigb.--tbis, tyPe in a -molecule of chemicat -explosive mate- of hehavibk is -characteristic of many ex-- rial,- -energy- changes, accompsnying nu- ploSione, the prOdess 'being accomPanied clear- rearrangements are very much -by -the liberation -of a largo quantity of greater than those- aSsociated with chemi- _energy. in.a; -Very short period;:of time,cal-reactions: ',within a Ifinited space: the .basic requirernenrfor energy a:0 'The'iitodOCti of the decompOsition release is-that the total mass-Of the'inter- of conyentionali*Plosives;are mainlyin- acting species should be greater than that 'trogen sanit :Olxi.des of nitrogen,- o/ides of of the resultant product (or products) of oitibok-'*itter Vapor, and' Saida, notably the 'reaction. As we saw in ChOter tarbOri, *iii* are read ily- disaipated in- the there is a definite equivalence between 'Therefore, the sub- mass and e. rimy. thus, -when a decrease 2stanceS- è iiiiafter the explosion do of-massliccura in a .nuelear -reaction, there no inorehernythin-the peisondus 'Carbon isan aecompariying -release of a certain nion OXide preSent 'in ,the 'exhaust gases amount of 'eriergy reIated-to the-decrease *lien -atitoM,Obile-,and airplane-engines.are in mass. In ;addition ,to the necessity for 'Operatectin:theq)pen.,air. the nuclear Prog4S?to he_ one in which NVIth a1 contentional explosive the there is 'a net_44,eale in mass, the J.elease Chemical:molecnies. comprising the various of 'nuclear ene'relik amounts sufficient to atOnware-heldtogether by- certain forces, cause an explosion requires _that t 'he i;eac-

AQinetfme0 ,-.ptPitcl -to 4s. encbOTIO. tion shouldhe able to reproduce itself once it has been started., 'Two types of nuclear ,en-` the molecules undergo decomPosi- , ium 222)- tire nearly 6.0: -MeV and 1`SWIeVi- respeCtiVely. Generally speaking, any heavy nueleus can undergo fission if the egcitation energy is -large enough, e.g., fission of gold Occurs with neutrons of about 100 MeV energy.

FISSION FRAINENY ..ft + tesa .45N4INERAGE) + ENERGY ?VISOR FRAGMENT

HELIUM NUCLEUS PLUS

FIGUR.V 3.10-Fission of uranium 236 produces FUSION neutrons. -41bURE 3.9-...Fission Anil fusion- I FISSION CHAIN REACTION. interactimis whiCir can meet the require- 3.11 addition to the large amount of nientS for the production of large amounts energy released in nuclear fission, the sec- otencity in a shorttike-are FISSIOO and ond important feet, which has made possi- Ft.1,SrON. The fiSSiOn process takes place ble the production, of an:explosiones .a , Iffit*,001Tie: Of :the 'heaviest nuclei pligh result of fission, is that theprocess is atomic iMinber), Whereas the fuSionproc- accOMpallied, 0 the release of twoor more . ess-inVOlVes edine, of the lightest nuclei NEUWMS (Figure 2.10), Theneutrons (low atinnie- nUmber).($ed Figure 3.9.) thus liberated jn the fissionprocess, are, ' able to cause the fission of -other uraniuM, 'NUCLEAR FISSION' or plutonium nuclei.. In eachcase more -240 The- fiSsile materials whielt can neutronS are released; WhiChcan prodUce presently be used to produce' nuclear 'ex- furtbher fission, end so on: lierice,a. Single neutron:could zstartself;sustainedlekain, ploSiOris are the nraniuth isotopes T.23; of fissions, the number of nuclei jnvolved_ M235, end the pintoniunt isbtoPe Pu239. increasi at atreinendous rate. ent aneittrowentere; the nucleus ,ofthe 'apprOpriate atom- thenudleus splith tfis- , Sionslinto-tWo,daughter nuclei, and twolo 3.12Actually, 'not all the nentron; liS- threeneutrons(Pigure3,16). PorV233,JJ2:15, erated in the fission ;process,are available ,A114:13074!.(unlike,the;Caselortils,there is-for causing' more-fissions. Sbnie of these -noloWerlimitfor the .kin,etic energy thata neutrons esCape _and othersere lost in neutron must po Ssess. to enable -itto,ceuse non-tisSion r(ectiOnS.1 'It will 'be assuMed, fission-on ,captureby iv.mucleus ofany, of i3vievet, for 'simplicity, thakfor each ura- these:threeisotopes.. For this reason, niunr (Or 'plutonium) nugleus undergoing 'these isotopes Are7celle4lissile materiels, fisaion, there ere tWo neutrons produced and.,onlithese three=ere -of practical' sip.' capable 'Of initia.tirig 'further fission. Sup- the-cese of -e nonfissile nn-POse a single neutron" is,eaptpred by a Clatis,-.0* energy of the incident neutron nueleue in a guantity ofizranium,sothat -fission oceurs. Two neutronsere then lib- ,MOSte:xceed.a,,,certein .threshold,velue -to . , it-tO-eanse 'fission or 'capture. The A solf.sustalnEtt ihaln reactlort in purtrUngor puN nig or natural threshold, values for, Mt!' and.,Th2n (Thor- uranium itriot poulble. , .; 27- ".--erated-alid#0*eguietWonlore nuclei.to :underie.-fiSSion. ThidreSultS in the produc-. four neutrons aVailable for '2 s- Sion. _The fissions indrease by geometric progression (1,2,4;8,16732;64,128,256,- -..51471524,2048,4096,. and"- se., on)..By. the

eightY4irit step Of this .process, we have LIVIA liAlttat 1; 2;5, ,,x-102f fiSsionskenough to fission a kilo- ACIAT WalCAU, , -uranitim. The time re- FIGURZA.1.4,-Tamper -qUired:::for-the 81, steps is'1/208 seconds.. As you :dim See this tremendous activity then, if several pieced of fissile material, takei :place. almost instantaneously, thus totalling more than the critical amount, producingfan explosly,expaction. are suddenly brought together ihside a streng container or TAMPER (see Figure 3:13'_ Thegetual,, loss. of mass in the fis- 3.14) a nuelear detonation results. , sion.of urardurri,or plutonium is,only about. : What constitueS a CRITICAL mass de- one-teitth-ef a percent. of the total. That is, .. ifll the atomic nuclei in one pound of pends upon a number of factors, including uranium or plutonium undergo fission, the the density of the material (whether solid _decrease of niess would_ be roughly. five- metal pr in porous, spongy form); and also : tenths-of a gram or one-sixtieth part of an upon pe nature of the TAMPER and okince. Nevertheless, the amountufenergy whether it absorbs neutrons or can reflect released by the. -disappearanCe of this them back into the fissile Marge. onantity of platter would be about the 3.15Published information suggests ,Sameas that prodtteed hy thp explosion of that an unConfined sphere of U233 metal of,

,8;600 tens of TNT. , about. 61/2 inches diameter and weighing about 48 kirograms wonld 'be a' critical 00404-SIO. OF ,NUCLEAR FISSION amount; this would be reduded to abOut 41/2- inches. diameter (16 kg.), for a U233 sphere enclOsed in a heayy4,tamper (Pignre 3.14 When a piece of fissile material is 3.14). The"critical sizes for 1.12.3 and Pu239 bele* a certain size, a few of the atomsare have not been disclosed. Tbe increasing C9ntinually undergoing fission, 'butmore mechanical compliCation of bringing to- neutrons escape through its surface thangether, rapidly and simultaneously,a :" ire,proctiiCed in fission, and an increasing number of subcriticai pieces offissilema- Chain of fiSsione is not builtup. Such a g practical limit to the power of Mass iS celled SUBCRITICAL. On the.nuclear fission weapons. Another impor- 'other hand whena mass (in a giventant consideration is that the size of a sha'pe) is just great enough to support a purely ,fission-type homb, is limited be-,

suitaining, chain, reaction, it is called a cause, above a certain critical...size,. a, lump_, cluncAL miss. As we 'can readily see, of fissile material is- self-destructive. ° , (GEFORE DETONATION) (AFTER PETONATION fr -

NORMAL ,DENSITY SUSGRITICAL ACTIVE MATERIAL HIGH'DENSITY 'SUPERCRITICAL

HIGH EXPLOSIVE

8.16a. principle. 'PROPELLANT ACTIVE MATERIAL: 9 (EACH TWO-THIRDS CRITICAL)

e N"" , ,

`&11NNX V h GUN TUBE

(BEFORE DETONKTION) TAMPER: TAMPER FIGUitE 3.1.61iGun assembly principle.

3.16 As we have seen, subcriticalmas- FISSION AND FUSION ..AND ses or piedes of fissile material, when brought- together rapidlyean, under THERMONUCLEAR WEAPONS proper conditions, cause a chain reaction 3.17A. fissfon explo-sion produces and subsequent explosion. As avery nec- briefly and in a email space,intensities of essark safety precaution, it is obyious that light and heat comparable to those in the the masses of fissionable material present sun. A fusion explosion does stillmore: it- a nuclearbornb inirat be kept i&beritieal duplicates.a part of the actualprocess by mitittime for -the borrib to be detonated. which the sun and other stars produee Aiid:'When that time arrives,_the subcriti- their light and heat. This process-is not- CalMaiseS nuist fermia supercritical Mass chemical burning reaction. It iSa nuclear 'Ansi-an-W*3,01y. One ,..wair of producing fusion reaction, in -which, :four nuclei,- of- :Supercritical niasS4s. by 'forcing twoor simple hydrogen ,become one nude:AS-of inereSUberitidalniasseS tegether..Another Stable helium, with a converSion. of.mass te eilueoe a, subritiealmass to radiant energy. Through' thisprocess tikbtlY into a neW-Shape 'Andkra greater our sun, every seq,90, loses. about 4 ;to 5 deneity,'$Peli 'a Mass becothes Opercriti- million tons of matter, radiatedA'senergy: 'eal-Withoirt, the addition of any inOre stib- From experiments niade.,in laboratories stall& 'tirialatter filethod, first used iri with cyclOtrons and-similar devicesit was in concluded that man could' partially' the iniplosion prind,ple (kignre .3.160.In cate the, procss of the sun, by the-fusion -tbie boinb, a giYen amount-Of-fissilemate= of isotoies of hydrogen. This element is rialiauberiticalin the torin.of a thin spher-known tO exist in three iiotopie fornis in ical ibeit, became critical 'Whenc oth - Which tlie nuclei have Masses-of 1, 2, imd '.Preelfed intla Solid; sphere; This ,compres- 3, respeetiVeIy. Thege are gefierallyre- 'Sion Was )irortiOrtabOut by firing-specially ferred to as hydrogen (II1), deuterium (H2 labrieated -Shapea Pt 'ordinary high explo- or P2), and tritium (H2 or T2). Several. dif- .Siire arranged sphericallyon he vogoferent 'fusion, reactions have been ob., A*..).thlto* eitibere When the'served among the nuclei of the three,hy- ''-eXPliisiYe'it detonated,. the MOS' is OM- cirogen isotopes, involving eithertwo sim,V4 PreSsied; iMpiediatelybecoininet#Pereriti, lar or two different nuclei. In Order to. the-atornic detonation takes plade. makethese:reactions occur to an apprecia, the:otber inethow'as peed witihe Iliro-ble extentt the nuclei mu.st have :high Ship*beMb.' The SUbdritical inaSsia,en- energies. One way -in which: thisenergy 'Cf4eFt, in something Iike.a:gUirbaftel,were can be ensiled ie..by ineane!o4 a, charged- iniptfilect againit eiCh other by:=thepction particle itaelerator, s,uchs. k cyclotion, inernical ,eXplesiVes, (Vigure as mentioned earlier. 'Another possibility is tO raiSe' the ,:temperatyre to 'Yery; high lel!iels. In these circumstances, the' fusion 1 SELF-.SUSTAINED FISSION Proceisee are-referred -to' ae '"thetmonu- OF PLUTONIUM 239 ..elearteactione". 'ON URANIUM 235 .348: teiiveratures of the Order of a slegrees -ate-necessary in order to' 4he ,nuclear fusiOn teactions take -pIfice.`The Only-nown Way hi which such teniper#dre Caivhe.:obtained oh earth is ;by,Means,Of a:fissio4 extilosion-At temper- aturei.oi'Milliene-Of degrees, centigrade, THERM07 NUCLEAR atome ,ate ,stritped of.lnost of -their sur- REACTION' rOnticlineclaid,of'electrone an4 the nuclei 'MoVe 'vety high speeds experiencing Many collisiOni With one another. Under FIGURE 3.19,-"Fiesion-fusion reaction. theSe circuinStineeS, the nuclei of the type. In later weapons the deuterium is rater hydrogen isotoPes deuterium .aqd combined chemically with the metal lith- tritium have enough energY of motion to ium in the form of a white powder. Each overeeide the, repulsive forces between neutron (1 mass unit) released by the trig- their -ingle positive electrical charges aid gering fission bomb splits a lithium atom they-4*e able tO fOse together. The-energy (6 mass units) into the non-radioactive gas release4 in the fulion of these two nuclei helium (4 mass units) 'and tritium (3 mass iS,about one-twelfth of that-released inlhe units), and the latter fuses with the deu- fisSion, of a eingle tI35 nucleus; but on 'an terium atoms present in. the compound :equal weight:baek the fusion energy is'(Figure 3.19). There is nO* limit, other than .aboUtthree tiMes as lEirge ai the, energy Of the convenience of delivery, to the size of a -EissiO0 ofU.The, actual quantit4of en- fusion .or thermonuclear weapon, and it is ergY liberatea,fot a giVen mass ofanate-" claiined that lithium deuteride is less rriA déencIs on, the -particular isotope. (or costly than tisiile materials such asU233, )isotOpes),iriVoived in the nuelear fusion U23-5or .13u231'. ,I-teaction.:-,Fouit'thermonuclear- 'fusion xeac, tiona4trenOted below: . 3.20 , In considering. . Nteapon 'designs, it is ,posSible also to- have a fission-fusion- 4-1127§.11e3 +n +3.25 MeV fisSiOn type weapon (Figuie 3.20). :In the propos, of fusion, e neutron is released at +14,-.:4H1,s+H! +4.03 MeV. a vOy high speed and it ligs enough en- ergY io split the COintrionet, atoms of W .1.,1P,-5>He4 +n +17.5840V A thermonublear weapen can be designed _with a.,Ooreoffissile..M.# asa. fuSiOn 43 +43-3.10- +2n +11..3210V

,OF URANIUM 235 .where-Hi'-iErtha,-. . syMbol for helium and n s. -f(iriaSs..--4.),::repreSents a' neutron: The- en- re n+ ,04. 0+4.1111.4., ergy case is ,eXpressed . *,ii11ion=e1ettrbil-vOits-7(MeV): llieRMO": I . atone, -deutethim and, trit- NUCLEAR .et, 4. HID.144+ als nisswi iitOtepee'of the 'gaseptis element REAcTION 'ilydrogeri,haYe tof'he liqUefieit ;at a "very lifWemperature)andlinaintained there for cOntain*etit hi' -a- thermOmialear-deviCe. FISSION 'OF, uRANIum 238 afthough:it haa been. roPoite:d'hatthe'giisi4i*azicaiOhernion-t nelear device teatO '062 was, of"thia FIGURE 3.20,Fisaipn-fusion-fisaion reaction. . f) $.1 tor encased in,a heavy container of U. heat or thermal radiation, This U238 casing will the proportion undergo fission from'as well as- thequantity is much higher in the high-speedneutrons produced in the the case of the nuclear hydrogen fusion detonlition. weapon. The basic Since the ce.s- reason for this difference is that, weight ing might bemany times'heavier than the for weight, the fissile core of U235, energy produced in a nu- correspondinglY larger clear explosion is millionsof timei as greaf quantities of fission productswould be released as fallout from as that in a chemica explosion.Conse- such a Weapon. quently, the temperat1i.rereached in the nuclear explosionare much higher than in 3.21 A muchmore detailed discussion a chemical explosiontens ofmillions of of fission products willbe taken up later in degrees in a nuclearexplosion compared this chapter, but itmight be mentioned with a fe;:v thousands ina chemical explo- here thaall existing types ofnuclear sion. weapo release fission products.,"Dirty" 3.24 For a nuclear,detonation in the bomb producea great deal and "clean" atmosphere below loo,00p bom feet, about 85 produce little, the dirtinessdepend- percent of the totalenergy appears first as ing upon the ratio offission to fusion intense heat. As shownin Figure 3.24, energy produced by the bomb. Thedivid- almost immediiatelya considerable part of ing line between"clean" and "ditty" this. heat is converted boMbs is, thus, to blast or shdck; a matter of opinion, but the the remaining thermalenergy moves radi- fission-fusion-fission type ofweapon /neerally outward at the speedof light -as heat ) *tioned in paragraph 3.20would be a rela- and visible lights The tively "dirtk"one. remaining 15 percent of the energy of thenuclear explosion is released aS variousnuclear radiations. Of this, 5 percent ENERGY YIELD OF*ANUCLEAR constitutes the nuclear. EXPLOSION radiation produced withina minute or so of explosion, whereasthe final 10 percent 3.22 The power ofa nuclear detonation of the bomb energy is inthe form of resid- is expressed interms of the total amount ual radiation emittedover a period of of energy releasedas compared with the time. The residual radiationincludes the energy liberated by TNT when itexplOdes. FALLOUT we will discussin later chap- A 1-kiloton nucleardetonation' is one ters. which releasesenergy equivalent to 1,000 - tons of TNT which iscalled the kiloton TYPES AND'HEIGHTS OFNUCLEAR (KT). The advent ofthermonuclear hydro- DETONATIONS . gen,hombs made it, desirable touse a unit '13.25 Aswe have seen, an exPlosion is about 1,000 times largerstill, and theme- the release of a large gaton (MT) unit was.adopted. quantity of energy in It is equiva-, a short interval sof time withina limited lent to the energy releasedby the detonation of 1,000,000 tonsof TNT. The bombs detonated over Hiroshimaand Nagasaki, and those used in the1946 test at Bikini, released roughly thesame amount of en- ergyots 20,000 tons (or 20 kilotons)of TNT. In recent years, muChmore powerful weapons, with energy yields highin the megaton range, have beendeveloped.

. . DISTRIBUTION OF ENERGY 3.23 Although the detonationof chemical explosives, suchas TNT, and the deto- FIGURE 3.24.Distribution ofenergy in a typical air nation, of a nuclear blast of a fission weaponinair at an altitude below weapon both produce 10,000,1e.et.

,31 space. The liberation of this energy is ac- 1-megaton TN't equivalent nuclear bomb. companied by a considerable increase in The important aspects of a nuclear expia- temperature, so that the products of the tion in the air are summarized in Figures ex ldsion become extremely hot .gases. 3.28a to 3.e. ese gases, at high. temperature and pressure, move outward rapidly. In-doing so, they push away the surrounding me- THE FIREBALL diumair, earth, or waterwith great 3.29 ,As already seen, nuclear reactions force, thus causing the destructive (blast involving fission apd fusion in a nuclear or shotk) effects of the explosion. The term weapon lead to the liberation of a large. ."blast" is generally used for_the effect in Amount of energy in a very short period of air, because it resembles (and is accom- time within, a limited space. As a result, panied by) a very strong wind. In water or the nuclear reaction products, bomb cas- under the ground, however, the effect is ,ing, other weapon parts, and surrounding referred to as "shock" because it is like a air are raised to extremely high tempera- sudden impact. tures, approaching those in the center of 3.26 The immediate phenomena associ- the sun. Due to the-great heat produced by ated with a nuclear explosion, as well as the nuclear explosion, all the materials the effects of shock and blast, and thermal are converted into the gaseous form. Since and nuclear radiation, vary with the loca- the gases, at tjle instant of explosion, Are tion of the point of burst in relation to the restricted -to the region occupied by the surface of the earth. -For each weapon qf original constituents in the bomb, tremen- specific power, there is a critical height' of dous pressures will be produced. These burst above which .the fireball will n pressures are many hundreds of thou- touch the ground and, hence, it will no sands times the atrvospheric pressure,2 produce .appreciable contamination on the i.e., of the order ofirmillions of pounds per earth's surface. Although many variations iquare inch. and intermediate situations can arise in 3,30 Within a fraction of a second of the _practice, for descriptive purposes three detonatiA of the bomb, the intensely ha types of bursts are distinguished. The g at extremely high pressure appear main types, which will be defined below, as a r y spherical, highly luminous are air, surface, and sub-surface burst. mass. This is the fireball referred to in , _ paragraph 3.26. A typical fireball accompanying an air burst is shown inr gure CHARACTERISTICS OF AN AIR BURST 3.28a. Although the brig ss u creases 3.27 An air barst (frequently the most with" time, after aboqt a ednd,2 the efficieni means of accomplishing a mili-fireball of a 1-megaton nuclear bec- tary objective, and the type used' over plosion would appear to an observ r 60 Japan) is definedas one in which the bomb miles away to be many times as bright as is exploded in the air, above Jand or water, the sun at noon. 'f at such a height that the fireball (at maxi . 3.31 As a general rule, the iurninosity mum brilliance) does not totch the sur- of the fireball does not vary greatly, with face. The aspects of an air burst will be- the yield (or power)'of the bomb. The gur- dependent upon the actual height of the face.temperatures attained,' upon which explosion, as well as upon the energy yield the i?lightness depends,, are thus not very of the weapon, but the general phenomena different, in spite of differences in the are much the same in all cases. total amounte of energy released, is 3.28In the following discussion, it will 3.32Inlmediately after its formation, be supposed first, that the weapon detona- the fireball begins to enlarge in, size, en- tion takes place in the air at a considera- gulfing cooler surrounding air. The growth ble height above the surface. The descrip- 'The normal atmosphera pressure at sea level As 14.7 pounds per tions given here refer mainly to the phe- square Inch (PSI). nomena accompanying the explosidn of a Amillisecond is one.thousandth part ofa second. t

of the fireLll is accompanied bya about 220 feet;and this ..increases," decrea e in temperature (and pressure) maximum of about 3,600 feet in 10 seco'W../ and, hence, in luminosity. At tile same The diaMeter 'Ai thenfume 7,200*.feetand: time, the fireball rises, much liketr fiery the fireball is rising ;at the.rate 61 doughnut. As it rises, thereare tiparafts 350 feetesecond. One,ininue, after** through 'the center of the doughnut and'nation,e fireball 'has toole,k POO downdrafts on the outside. . emission of heat and-,eniiaiilinOtof.-046 3.33 Within seven-tenths ofa millise- air, to such an extentithtttA4V10,19110.17-J- cond from the detonation, the fireball from_jItininous._ t ,4t.a s, a 1-megaton bomb reaches a radius q'roughly 4.5 miles fron341tetAioiiit: 14.y t FIREBALL NUCLEAR 0:!1-H.ERK;A RADIATtON'

PRIMARY SHOCK 'FRONT

not= 3.28a.Chronological development ofan Mr

":" " Nu-CLEARa TIMA .":` RADIATIO . FRONt-, . -- REFLECTED S,HOCrFiONT COMMENCEMENT'OP-- 'MACH.REFLECTED DVERPfikSSPRE 116- PSI - .. ' 1;74-'4

MILIES 01, -I" 3 5I

FIGURE. a020:Chronological development of _an air burst: 4Tseconds i(jter1-megatan detonation. ,

...... -_...... _ ----;" '`---:=-P.k1MARY'SHOCK FRoNf ' ."...:',,, '..----\* .' NUCLEAR6 THERMAC.. N -RADIATION,',, .

,REFLEOEDSHOCK PRONT i .d!..,,,.. ,t IND VELOCify'.I MACH_FitoNT ISO MH P ., 1---OVERPikESSURE 6PSI % ..' . ','.: ',...:::,..:';':::..,;,:,':7'...-;,:

MILES-I i T I I -. I - , 4 3 ci-dt 5 6 ' 4 01611E'3:28e.r7Chnol . 'cal. deilelopmert of an air burst: 11 seconds after1.inegaton detonation. , . . '.., . , 3 REFLECTED, SHOCK 'FRONT.'- \-" ifmiktoifri 1110,4 FRONT\ -%%\. . \

NUCLEAR PtApIATION.

HOT-GASEOUS BMB'RESIDUE , .

, MACH FRONT _OVERPRESSURE [PSI *1 -AFTERWINDS WINO VELOCITY- 4oMPH

. MILES1 1 I 1 -I -I I I ' 0 I 2 , 3 5 6 7 8 9 10

I - I I I TOTAL THERMAL RADIATION. CAL SO CM- 30 .20 . - -, 8 5 Fiat,' ix 8.24.C.Ilroologieal dwielopment of .an air burst.: 3t' seconds after 1-megaton detonation. ,

RATE. OF FiItE 130=170 MPH

RADIOACTIVE CLOUD .

WIND V,ELOCITY 275 MPH

L,fiDtiRli-848ev-,c,hreixiieekai-d,evekrneet-or ati-air-inirat:110 secoiids after 1-nriiiton detonation.- attained ita maximum size (7,200 -feet ihe blast froot is sonie-a itiiles . of ksecond after, theftirther ahead. About a 'minute after the ,, de4rUCtive high-presSUre explosiort,, whert ihe firehall is no liinger ,*aVe Aevelops:I4 The. shaaroubd the fire- the blattt waye has traveled ap- 'Ilan and ,moVes i!aPi4iy away, behaving proxithately 12 miles. It is then, moVing at a-Maiing, *ail of,highiy compreSsed.about 1,100 feet per second', whith is 'air..Aftemthilapse 'of 10,seCOnda,when the Slightly faster than the speed of sound at --firebalrat 4-714-egateninUclear -,66M6 ihas'-sealeVer REFLECTED WAVE I- "INCIDENT WAVE

t 1 1-- I.

/ X / / TRIPLE POINT -y , / MACH STEM I 1.P .7.771" -

FIGURE 3.35.--Fusion of incident and reflected waves and formation of Mach stem. THE MACH WAVE 3.36 For a `typical" air burst of a 1- 3.35 When the blast wave strikes the megaton nuclear weapon, the Mach effed surface of the earth, it is reflected ina will begin approximately,5 seconds aftek' wayailmilar to asoundwave producing an the explosion, in a fough circle at a radius. _ echo. This reflected blastwave, like the Of 1.3 miles. frpm ground zero. -The terM _- original (or direct) wave, is also capable of "GROUNP, ZERO" referS to the point on causin,g,material damage. Ata certain re- th. earth's- surface immediately below (or ' gion -on thesurface, the position_a_which abovathe isoint of detonation. . depends ChieflY On the height of the burst 3.37 At first, the height' of the Mack above the suifaCe and the eneigy of the front it small .(Figure 337), butas the eXplosion, 'the direct and _reflected blast blattfrónt continueis tomove outward, tile,: liontig, fuseas shoWn in FigUte 3.35. This height-increases steadily forminga fusion phencnienon its called the MACkSTEM.. During this time, ,however, theoV- EFFZCT. thefNE4PEE8s00, the erpreSsure, tbe original blaSt ressnie ottke--blast watrein-eXcess Of the Wave,. decreases correSpondingly because.,.. non* atirioSpheric value, atthe front ofof the continuous loss .pf_energy and the- tne MaCii- lkgenerallYaboUt twiceas eyet-indreasing, area of;:the.. -advancing Otat aS that it the direct slioCk front. Tbe front. After the lapse of'about 46isecondi,,ci, inixininin'XiVerPketsure Valne,i.e., at tbewhen the gioi fiont froma .1"-Eaagatoh,-, ;Wit ftent, is called the Peakoverpres- nuClear bombis 10 miles fromigreArkii-zero,_ si0e; fhp overPieSsure have: necrease'to-tt t-WLZtTLD I =1/IdOeNT. IIIt

PAIN OfTRIPLEtOilti

z ' 41','. 4' 71, cr. 41614 tjr Irjd' , " C' t FIOX.M#8:37:0.1.itWard motion oi ,thet-121.as.t...arSve near hei4urficelh`the Mitch region: roughly' 1 pound, per square inch. Most of POSITIVE AND NEGATIVE PHASES the material damage caused-by an air burst 'nuclear bomb is due mainly-zdi- 3.40 As the blast wave travels in the reitiyor indirectlyto the blast (or shock) air away from its source, the'. overpres- *aye. _The majority of structures will suf- eures at the front steadily debrease, and fer Isome damage. from- air .blast, when the the pressure behind the front falls off in a overpressure in the blest wave is about regular manner. After a,s17414.,thne, 'When the blast front has traVeled'e certain dis- one-hallf pound per square,inch or more. tance frtrar the fireball, the jiressure behind the front drops below that of the 3.38 The distance from ground zero at normal atmosphere and a so-called NEGA- which the Mach stem commences, and to TIVE PHASE of-the blast wave forms. In which an ove6ressure of one-half poundthis region.the air pressure is below that of per square inch will extend, depends on .the original (or ambient) atmosphere. the yield or size of the explosionandon the height of the burst. As the height of 3.41 During the negative=overpressure the burst for an explosion of given energy (or suction) phase, a partial vacuum is is decreased, Mach reflectioncommences produced and the air is sucked in, instead 'nearer to ground zero, and the overpres- of being pushed away, as it is when the sure at the surface near ground zero be- Overpressure is positive. In the positive (or comes larger. If the bomb is exploded-at a compression) phase, the wind associated greater height, the, Mach fusion com- with the blast wave blows away frOm the mences farther away, and the overpres- exprosion, and in the negative phase its sure at the surfade is reduced. An actual direction is reversed. contact surface burst leads to the est 3.42This wind is dten referred to as a possible overpressures near grounzero, "transient" wind because its velocity de- cambia ñ Via effect occurs, sinceere is creases rapidly with time. During the posi- no reflected wave. tive phase, these winds may have peak velocities of severel hundred miles per 3.39IT; the .nuclear explosions over Hi- hour at points near ground-zerk and even roshima and Nagasaki during World War at more than 6 miles from the explosion of* II, the height of, burst was about 1,850 a 1-megaton nuclear explosion, the peak feet. It was estimated,.and has since been velocity may be greater than 70 miles per confirmed by nuclear test explosions, that hour. It is evident that 'such strong winds a 20-kiloton bomb burst at this height can contribute greatly to the blast damage would cause maximum blast damage to following an air burst. The peak negative structures on the ground for the particu- values of overpressure are small compared lar targets concerned. Actually, there is no with the peak positive overpressures. single optimum height of lourst, with re- Thus, it is during' the compression phase gard to blast effects, for any specified ex- that most of the destructive action of blast Plosion energy yield, because the chosen from an air burst will be experienced." height of burst will be determined by the. However, the winds associated with the nature of the target. As a rule, strong_(pivnegative phase can be quite damaging to h,ard) targets will require low air or sur- eakened structure's. face bursts. For weaker targets, which 'are '3.43 From the practical viewpoint, it is estroyed or damaged at relatively lowof interest to visualize the changes of ov- overpresSures or dynamic pressures (the erpressure in the blast wave with time at dynamic pressurejs a function of the wind a fixed location. The variation of overpres- Velocity and air density, behind the blast sure with time that would be observed at front), the height of burst may be raised in such a location in the few seconds follow- order to increase the area of damage, since ing the detonation is 'shown in Figure the distance at which low overpressure 3.43a. The corresponding general effects to would result would bel extended because of be expected on a light structure, a tree, -the Mach effect. and a small animal are indicated at the, 43 c't ;44. 7t

Ell

C.,

PRESSURE PHASE

a a1:3'a' et==0 4 0

4 SUCTION PHASE

a.'ariation of pressure with time atafnced location and effect of blast wave passingover a . `struettire. ,0-4 left of the figure. Additional data ispre- all of these fourways, depending -upon sented in Figures<3.43b ind 3.43c. many factors, including the degree ofprotection, closeness to groundzero, size of 'BLAST CASUALTIES, boMb, height of detonation, etc.. . 3.45 The four kinds of blast injuries 3.44 There are four different kindsof are: 4 injuries caused by the blast of an atomic (1) primary blast injuries, caused by weapon. Victims may be injured inone or the high pressures of the blastwave;,- . 37 4 4 a- ..,.. -1 t ti a lk-I

A II11,:4q LIGHT DAMAN TO WINDOW MANES AND DOORS. MOD(RATE * .,... PLASTER DAMAN OUT TO NOUT IS MILLS; GLASS ICEMAN -50_-- 44445 -0.036 - 12' POONA OUT TO 50 NW.

` 51 3.45 - 0.049- 14 PIN MUM iums. lama

740 60 - 3.44 - 0.072 -1.7 SMOKESTACKS DAMAGE. 1.- 7 ... WOODFRAME aumpaoss, NOCIERATE OAMASE. RAM AMC TV TRANIAITTINS TOWERS MODERATE DAMAGE. 72 7 3.43 - 2.1- W030-FRAIN linLoons.saysite *was. mimic a POWER UNESLINIT OF SIGNIFICANT OAMAGE, , 111iLL-NANKIL NICK RADOM (APARTM(RT NOUN TYPE). 99 - 3.40 - b.16 - 2.6 MOOERATE'DAMASE. WALL...EARWIG. BRICK MALMO (APARTM(NT HOUK TYPE ) SEVERE DAMAGE. -5- UGNT sTrli-samas. INDUSTRIAL sun.saws,m000mit DANSE. 117 3.24 - 0.28 - 3.5 -45 uoir STEtlerRAIRE, IICUSTRIAL SUILDINDS.SEyERE DAMAGE. MULTISTORY CALL- KARIN SIRLOINS (MONUMENTAL TYPE) 4 MOOERATE &Jaws. 302 - Q60 - 5.5 MULTISTORY ISALL-SEARING SUILDINGS (MONUMENTAL TY-PE) -20 177 MERE DAdASE. INMOST AND RR TRUSS NUNES. MODERATE DANADE. YULTistoar,sym.-FRAke GOLDING (OFFICE TYPE). SEVERE 715 278 - 2.69 - 140 -9.4 3 DAMAN TRANSPORTATION 'VEHICLES. MCOERATE DAMAGE NOLTISTORY. REINFORCEDCONCRETE FRAME BUILDINGS (OFFICE 2.25 - 5.22 -18.0 2 TYPE). SEVERE DAMAN. -10-- 464 MULTISTORY.SLAST-RENSTANT DENNED. REINFORCED CONCRETE MODERATE *Januar. BLAST- PIENSTAgrtweaso.atowoacmillitarrs - 5 307 1.75 - 3.60 - 27.0 -0- SUILDININI. SEVERE. ALL ME* (MOVE GOMM) STRUCTURES. SEVERELY DAMAGED OR -o DESTROYED.

FIGURE 3.431xDamage ranges for a 1-MT typical air burst.

(2) thosefrom the impact of missiles cause varying amounts of dirt ,and debris thrown about by the force of the blast; to be sucked up from the earth's surface (3) result of being thrown about by the into the atomic cloud. (Refer to Figure -blast; and . -3.28e.) (4) miscellaneous injuries, such as ex- 348 At first, the risini mass of bomb posure to ground shock; dust inhalation; ,residue carries the particles upward, but

. fires caused by the exploSion, etc. after a time, the particles begin to spread .e.venty -percent of those who Bur- out and fall slowly under the inflnence of , viyed, the nuclear bombing in Japan suf- wind and gravity. This is FALLOUT. fered:from; biastinjury. gince many of the --- ' 'suryivorawere'alsoinjured in other ways THERMALRADIATION twilit-Tan-Or radiation-bOtIr-to-be:~dis- eu,ssed-later).ww.cannot sarthat this is the .3.49Immediately after the fireball is .percentage oflnjuries caused by blast. formed, it starts to emit thermal radiation. istevettlieles5Tblast; war-one of tpe or Because of the very high temperatires of and,- certainly, a- major the fireball, this radiation 'conSists of visi- causes of ble light rays, invisible ultraviolet rays of Pauie ofdeath. shorter wave length, and invisible in- THE ROMI-(RADIOACTIVEYCTOUD ., , , frared riq4s of longer wave length. These 147, In,additidn to the transient winds rays all travel with the speed of light. Due associated with the passage of the, blest to certain physical phenomena associated front, _a strong, updraft with inflowing with the absorption of the thermal rhdia- winds, called "afterwinds", is producedin tion by the air in front of the fireball; the , the;immediate vicinity Of the, detonation surface temperature of the' fireball under- du-Fro:1M riiing.fireball. These afterwinds goes a curious change. The teMperature 45 ._. . EXPLOSION YIELD , STRUCTURE TYPE DAMAGE S .AbIstallia- in milts) i0O-XT-: t iMtI IoMT . . . : _ . . . 'MODE/VI 3-,2 .6.6 14 - WOOO-FRAMEEiull..pING-, 1 RESIDENTIAL TYPE .

-, SEVERE '. \- 2.4 '5.5 12 .- . -

, . I WALL-KARING, MASONRY, MODERATE 4.7 10 BUILDING, APARTMENT HOUSE TYPE SEVERE 1.7 3.5_ 8.7

.. - MULTISTORY, WALL- MODERATE 1.8 3.5 7.4 BEARING BUILDING, : MORUAIENTAL TYPE . SEVERE, 1.3 2.8, 6.1

. REINFORCED CONCRETE . MODERATE 1.5 3.4 1 i/97-EARTHQUAKE ' 7.2 RESISTANT) BUILOING-, CONCRETE 'WALL, SMALL . ; WINDOW-AREA, , SEVERE El-

'FOR A SURFACE BURST.THOESOIOTIVE DISTANCESARE THREE QUARTERS OF THOSE FOR AWAIR.11,11RST OFtiit'SAMEYIELD;

-Pittaa4:43c;;-kaximunirankialroin. , ground zerbfor structural-damte fronv air bursts.-

diereaSet rapidly fOra fraction ofEt Eec- aOCOrrespondingto the two tempera- OnL surface_ temperatuip' ture Puises,, there -are two pulsesvf emis, ore:Saes-40in for a sonieWhat longer time, siOn-of.thermal radiation from the:fireball $fter z%Ithich :it falls-continuously. In other_ (Figure 846).. In the. first Puliel which wercls,, thereare ,effee*efy two su'rfSce- lasts about a tenth Ofasecond for a 1, teni' erat. plosion, the temperaturesare 'shOrt -duration, 'whereai the Second lasts mOStly Very 'W.A.-Asa result,,Inuch of -the for a Mutklonger time. This behavior isradiation aMitted ,in thiSpulse is in -the -itUiteStaridard With all-size apon$,al- ulttaViolet r a ura ionImes- o t e two Of ultrairiolet radiationcan _produce pain- pUlgesincrease with the energy -yield of ful *blisters; in Tnilder-forM. the wig:60On. After:about these .effeots seconds -from are familiar aS simburn.'However, inmost the-detonation-0f a 20 ICT bomb, the fire- circumitances, the .first pulse Ofthermal balL-14hoUgh Stillvery hot,:has cooled, to radiation is nOt A-significanthazard, with luotfineittent-that t e thermatradiationregard: to Skin hurns,Jorseveratreasons. its :n6-1OrtgerinitiOrtant, whereas 9Mounts In the first place, only about1 percent of ot AO:Mat-radiation still continueto hethe thermal radistion,appears in the ini- -en:IWO-fro* the-firebalt at 11 sedond tial pulie because ofl its short-duration. 'titter 1.'1=inegiton Oplosion. econc), the ultraVioletrays are ,reach.ly glisorbed in the atmosphere, so that the burns due to a nuclear explosion into two dose delivered at a distance from the ex-,classes, namely (1) primary burns, and (2) Plosion 'may be comparatively singlkFur- secondafy burns. As in the case of blast

5 ther, it appears that the ultraviolet radia- injuries, the terms primary and secondary tion from the first pulse could cankisignif- refer to the manner in which the burns i6nt effect on the human skin onlY within are inflicted. Those in the first class are a ranges where peoPle would he killed out-, direct result of thermal radiation.from the right by the blast and at which other bomb, while those in the second group radiation effects are much more serious. Arise indirectly from fires caused by the - 3.51 The sitUation with regard to .the . explosion. From the medical point of view, second pulse is, however, quite different. a burn is a b`urn; wlietherreceived -g's a This pulse may last for several seconds flash burn from the initial thermal burst and carries about 99 percent of the total or, at a later time, from the burning envi- thermal radiation energy from the bomb. ronment. Since the temperatures are lower than in 3.53Experiments in the laboratory and the first pulse, most of the rays reaching in the field have established criteria for the earth consist of visible and infrared assessing the degree of thermal damage to light. It is this radiation which is the main be expected for doses of thermal radiation cause of skin burns of various detrees delivered to human tissue within specified suffered by exposed individuals out to' 12 time limits. Medical diagnosis usually re- miles or more from the explosion of a 1- cognizes three grades of thermal injury: megaton bomb, on a fairly clear da.y. The first, second and third degree injury in warmth may be felt at a distance of 75 ascending order of severity. A first-degree miles. For air bursts of higher energy burn corresponds to a .moderate sunburn yields, the corresponding distances, will, of or erythema. Such damage, while quite -course, be greater,GeherallYi thermal ra- painfutis -r eparablewitltime andre diation is capable of-cripsing skin burns on quires no special treatment beyond the exposed individuals at such distances from relief of pain. The second-degree burn in- the nuclear explosion that the effects of volves the skin thickness down to and blast ,and of the initial nuclear radiation including portions of the dermis. A charac- are not significant. teristic feature of second-degree burns is the formation of blisters. The second-de- THERMAL RADIATION CASUALTIES ,gree burn is extremely pdinful but also 3.52It is convenient to divide thermal reparable with time. Infection usually occurs' since the protective barrier of the epidermis las been pierced, leaving the tissdes open to infective pathogens. Given 6S to- .. time and Opportunity to combat infection, 2 OA the majority of second-degree wounds heal without undue aftereffects though per- .I___ Manent pigmentation changes may persist. The third-degree burn *nvolyes complete it).t.5,0 destruction of the- Av ole--skin- thickness. "4.0 Except for very sma area burns these are S ig 3 3A \. not reparable with time but require skin 6 2.0 " grgfting in all cases.. Infection is invaria- . bly present. Paradoxically, the third-de- 4 W gree burn is not as painful as the second-

1.02.0 30 4.0 5.0 40 70 0.011.0 100 11.0 12A degree burn because the nerve endings TIME AFTER EXPLOSION have been destroyed; yet third-Uegree (RELATIVE SCALE) burns to more than 25 percent of the hu- FIGURE3,50,--Emission of thermal radiation in two man body area might represent. a .fatal I ' pulses. injury. . 40 -

3.54The' treatment ofsevere thermal-22 times greater (since V500= 22 approx.). njury on areas in.excess of 25 percent of But the heat from the larger bomb is the whole body represents a grave medicaLspread over a much longer period, 20sec- problem e'ven in a modern hospital and onds compared with a 11/2 second -flash under the best of circumstances. Formass from the 20KT bomb, so thatmore of the burn casualties under field conditions the heat is dissipated. _situation takes, on- overwhelMing 'propor- 3.58 Nucieltrweapons of 1-0-100KT&- tions. An unwarned urban population Hirer at least 60 percent of the total caught out of doors duringa nuclear at- ther- , -tack-would -suffer-almost-tomplete-annihi=-mai radiation from the second radiation pulse in less than 0.5 secoRd. Weapons in lation from blast and thermalenergy out to a radius of many miles from ground the 1-1ogT range, while pkducingmore zero. While it is feasible to avoid the thermal energy overa greater radius from the burst than weapons of 100KTor less, prompt thermal flash by takingcover, it is deliver this thermalenergy at a .much not so evident how to avoid the secondary slower rate than the small effects of the burning environment which weapons. Thus, "3 for equal thermal doses incidenton tissue, develops soon after the burst. It is proba- the small weiiponsare more effective in - ble that burris from secondary firesengen- producing thermal injury because the dered by the bomb would representa major proportion of the casualties, large weapons reqUire anywhere from 5to even for a 15 seconds to deliver 60 percent ofthe population which had-received warning of thermal dose. For ekample, it requires 7-9 imminent attack. (From 65-85% ofthe atom bomb survivors in Japan cal./m.2 to produce second-degree burns were from a 10MT weapon. This illustratesa burned to some degree.) Figure 3.54_shows most important factor: The larger the the ranges in miles at which people, in the weapon, the greater the time available for open would suffer various degrees of skin burn from surface burst evasive dction. However, evasive tactics weapons of differ- must be exercised before 60 percent ofthe ent power. total energy has been delivered. For per; .sonnel well indoctrinated in evasivetac- THERMAL EFFECTS OF WEAPONS OF Mei, this couldmean the difference be- DIFFERENT YIELDS -1tween a moderate sunburn andsevere 3.55 A 19MT Weapon radiates 500 times /thermal injury. Figure 3.56 shows thermal as much heat as a 20KT. bomb. According energies required, tocause first, second to the "inyerse square" law and third-degree burns from different a 10MT yield Weapons. weapon should produce thesame amount of heat as the 20KT weapon ata distance 3.57 Temporary or perthanentblind- ness could be caused by the thermal radia- 44911 IN MILES ..., _

wf.APON POwER Det.Oirot T410 20 KT I00 Kr I mr 2 mi 5 WI' I04r 147 50 a 10047 MIT 10MT 20103 . 1

FOIST DEORa 1044 I 5 30 FAST COKE IlluM4 2.0 2.5 23 r II 0 I tO 150 210 3 2: 3.7 3.11

54:0ito 0034(1 SIAN 4 I %CM DOME MUM t-0 2 0 5 5 7 5 110 150 49 54 12 7.2 7.5

12 TWO DEGREE Num . TM° ef.04F_E MAN 0875 I 5 ' 80 7.3 S I 94 OS 114 475 425 85 13.0 "

FIGURE 3.56.---Approximate thermal FIGURE 3.54.---Range of effects from surfacebursts energies in Call cm.2,required to cause skin burns inair or surface on people exposed in open. burst. 13 41 tion if a person is looking ip the general the amount of thermal energy reaching a direction of-the fireball at the precise mo- grokind, target. ment of detonation. T.he lernk of the eye 3.61It.is.important to understand that* focuses beat as well as light rays on the the decrease in thermal radiation byTOg retina of the eye. Thus in addition to tem- and smoke will be realized only if the _porary_or !flasrblindnessof a few sec- burst point is above or, to a lesser extent, onds or minutes duration froin the intenSeirithin the fog (or- similar) layer. If the light, actual burns of the retina could oc- explosion should occur inmoderatelY` clear cur from undue amounts of thermal radia . air beneath a layer of cloud, or fog, wine of tion entering the eye. Neither flash blind- the radiation which would normally pre- ness nor retinal damage constitute major ceed outward into space will be scattered hazards during diylight because of natu- back to earth-. As a result, the thermal ral restriction of the diameter of the pupil energy received will actually be greater which limits the amount orlight entering than for the same atmospheric transmis- the eye; furthermore the blink reflex, one sion condition without a cloud or fog cover. . hundred and fifty thousandths of a second, 3.62 Unless scattered, thermal ra:dia- protects the eye from undue amounts of tion from a nuclear explosion, like ordi- 'radiation, except in those eases where the nary light in general, travels instraight thermal pulse is delivered within.ex- lines from its source, the fireball. Any tremely short times. This is the case for solid object, opaque material, such as a low-yield weapons and can also be true for wall, a hill, or adree, between a given object high altitude bursts. and the fireball, will act Us a shield and , 3.58It is an interesting fact that provide protection from thermal radiation. among the survivors in Hiroshima and Transparent materials, on the othet hand, Nagasaki, eye injuries directly attribut- such as glass or plastics, allow thermal able to. thermal radiation appeared to be radiation to pass_through, only Slightly relatively unimportant.' There were many absorbed. cases of temporary blindness, occasionally 3.63 In the case of an explosion in the lasting up to 2 or 3 hours, but more severe kiloton range, it would be necessary to eye injuries were not common. take evasive action within a small fraction 3.59 The eye injury known as keratitis of a second if an appreciable decrease in (an inflammation of the*cornea) occurred thermal injury is to be realized. The time in some instances. The symptoms, includ- appears to be too short for suchaction to ing pain caused by light, foreign-body sen- be possible. On the otherhand, for explo, sation, lachrymation, and redness, lasted sions in the megaton range, evasive action for periods ranging from a few hours to taken within a second or two of the ap- several days. pearance of the ball of fire eould reduce . the severity or injury due to thermal radiation in many cases and may eireh prevent injury in others. OFECT OF SMOKE, FOGAND SHIELDING

3.60In the event of an air burst occur- NUCLEAR RADIATION ring above a layer of dense cloud, smoke, or fog, an, appreciable portionof the ther- 3.64It was stated in paragraph 3.4 that mal radiation will be scattered up*ard one of the unique features or a nuclear from the top of the layer. This scattbereckexplosion is that it is accompanied by the radiation may be regarded as lost, as faremission of various nuclear radiations, as a poini on the ground isconcerned. In These radiations, which are quite different addition, most of the radiation which pene- ,from thermal radiation, consist of gamma trates the layer will be scattered and very rays, neutrons, beta particles, and a small little will reach the given point by direct proportion of alpha particles. Essentially transmission. These two effects (smoke orall the neutrons and part of the gamma s log) will result in a substantial decrease in rays are emitted in the actual fission proc- 42 49 esti. That is, these radiationsare prodUced on the characteristics of a 20-kiloton nu- Siniultaneously with the 'nuclear explo- clear bomb. For a bomb of higherenergy, sion, whereas the beta particles andthe the maximum distanceover which the remainder of the gafnmarays are .liber- gamma rays 'are effective will be greater ated'from fission products hi thecourse of than given above. However, at thesame their radioactive decay.The alpha parti- time, there is an iriirease in the rate at cles result from the, normal radioactiye which the Cloud, rises.;Similarly fora bomb 'Idetay ot the 'uraniam or plutoninmthat Of lower energY, the effectivedistance Is has escaped fission, in the bomb.* less, but so is the rate of ascent of the' 3.65 Because of the nature of the -phe-cloud. The period over which the initial nomena associated with a nuclear explo-, nuclear radiation extendsmay conse- :sion, either in the air ornear the surface, quently be taken to be approximately. the it is convenient for practiCalpurposes to same; napiely, 1 Minute irrespective of the consider the nuclear radiation as,being energy *ease of the bomb. divided into two categories; namelY, initial 4k69. -Neutrons produced directly in the and residual. --- thermonuclear reactions mentioned in paragraph 3.18 are of.special significance. INITIAL,NUCLEAR RADIATION Some.of the neutrons willescape but oth- 3.66 -The initial nuclear radiation is ers will be captured by the various nuclei generally defined as that emitted from the present in the exploding bomb. Theseneu- fireball and the atomic cloud within the trons absorbed by fissionable speciesmay lead to the liberation. of more neutronsas firat minute after the detonation. It in-ewell as to the emission of cludes neutrons and gamma rays givenoff gamma rays, almost instantaneously,as Velt as the just as described above foran ordinary gamma rays emitted by the radioactive fission bomb. In addition, the capture of fission products in the 'rising cloud. It neutrons in non-fission reactions isus- should be noted that, although alpha and ually accompanied by gammarays. It is beta particles are present in the initial seen, therefore, that the initial radiation radiation, they have not been considered. from a bomb in _which both fission and This is-because they are.so easily absorbed fusion (thermonuclear)processes occur, that Olty will-not reachmore than a few consists essentially of neutrons and yards, at most, from the atomic cloud. -gamma rays. The relative proportions of these two radiations may be somewhat 3.67 The somewhat arbitrary timepe- different than for.a. bomb in which all the riod of 1. minute for the duration -of the energy released is due to fission, but for initial nuclear 'radiationwas originally, based upon the following coniderations.'present purposes, this difference_may be i; disregarded. The range of lethal effects -; As a-consequence of absorption ,by the air, "from. initial nuclear radiationare well the effeetive range of the fissiongamma within the areas of severe blast andther- rays -and thoselrOm the fission prodtibts mall damage. . from a 26-kiloton explosion is very roughly words, gammatraydorigis nating from, sucha sOurce-af an altitude of RESIDUAL NUCLEAR RADIATION ' over 2 Miles Can be ignored as tar tul their effect at the earth's surfaceis toncerned. 3.16 The radiation which-is emitted 1. Thus, when the atomic cloud has reached minute after a nuclear explosion is defined a height of2 miles, the effects of the initial as residual nuclear radiation: Tliis radia- nUclear radiationare no longer signifi- tion arisedmainly from the bomb residue; cant. Since lt,takes roughly a minute, for that is, from the fission products and, toa the cloud to rise this distance, the initial lesser extent, from the uranium and plu- nuclear radiation is definedas that emitted tonium which have escaped fission. In ad- in the first minute after the explosion. dition, the residue will uSually contain some radioactive isotopes formed as a re.; 3.68 The foregoing discussionis based suit of neutron Capture by bomb materials. 43 - -A.notheraourceotresidual nuclear radia- 3.74 An important 'difference between a tion, it the actiVity induced by neutrons- surfaCe buffet and an aik burst is that in the .captured-1n various elements .present in surface burst the atomic cloud' is much theearth, in the.sea, orin.the substances more heavily loaded with .debris (and so ,whieh may,be in the explosion environ-, producesmuch more FALLOUT). This Will- Merit., consist, of Particle s. 'ranging in siie from 3:71 .';iTifit,h1surfaceitand,iespecially, sub- the very-small on,ea prodneed y condens,a- , -"surface,eltPlOsions;,the demarcation be- tion ai the 'firehalt Coeds, tO th# anuch larger particks which have been raised by .tWeen-initial:and residual nuclear radia- -. tion.iisnOt as-definite.some -Of the radia- thOtirfaee winds. The exact comPosition -tion:from.the -bomb residue will be within of The:cloud will, Of cenrse, depend on the the range of the earth's surface at, allnature Of the terrain and, the extent bf tiineaso- that theinitial and,residual.cate- contact with the. firéballi goriee merge Continuouily into one an- -&75 For a surface burst asaociated other. -Oor. very deeP.underground and un- with a moderate amount of debris; as was derWater burstar the initial gamma raysthe case in several test explosions in and neutrons produced in thefission proc- which the bombs were detonated near the ess maybe ignored. Essentially the anti ground, the rate of riae of the .cloud is nuclear radiation of importance is that much the smile as given earlier for an air arising-from tbe, bomb-residue. It can con- burst. The atomic cloud reaches .a height sequently be treated as consisting exclu- of several miles before sPreading ont into sively of the-residual radiation. In an air.a mushroom shape: arid surface burst, however, both initial 3.76 The lorization of dirt and other and; residUal .nuelear radiatiOn _must be material when, the fireball has touched the takeninto*sideratiOn. earth's surface, and the removal of Mate- 3.72 :Oneadditional iMportant cOnsider- rial by the blast wave and, winds accompa- ,ationof nuclear radiation is that the resid- nying the explosion, result in the forma- ual:nuclear radiation can, under some con- tion of a orater. The size of the crater will ditions,,represent a seriouskaxard at great vary with the height above the surface at clistanees. from anuclear explosion, wedwhieh the bomb is exPloded and with the beyond tke range of blast,, shock, thermal character, Of the Soil, as well as the energy .radiation,, and initial nuclear. radiation: of, the boMb. It is believed that for a 1-

_ This phenomenonFALLOUTwill be dis- megaton 'bomb there wodid be no apprecia- cased'at lentth in later chapters. ble crater formation unless detonation oc- cure at,ari altitudeoft450 feet or less. 3.77If-anuelearb,ornb is exploded near CHARAtTERISTICS OF A SURFACE 'BUitST ,s the surface of the. water, large amounts of 3.13- In .a.surfacebUrst,,the ball of fire water Will be vapOrized and carried up mite rapid ihitial growth will touch the into the atornic clOud. For example, if it is surface ,of the earth. Because of the in- supposed, .as abOve (paragraph 3.73); that t tentie.heat. a considerable, amount of rock, percent of the energy of the 1-megaton 8,4411Aieofharniateriallocated in the, area boinb Is expended in this mariner,, about "/ Will,be yapOriZed and taken into the bail of 10,600 tons 41 'Water' will be coriVeited Ik 'has. been estimated 01,4;0 only. 5 into vaiior. At high altitudes this will con- perce4 of a -1"Inegaton bomb's:energy is dense to form water droplets Similar- to spent Uythisjoanner, soroething,like 20,- those in an ordinary atmospheric clond. 400 ions. of Vaporized, soil material Will be addetto thmormale cOnstituentsof the AIR BLAST AND GROUND SHOCK firebill.inaddition,the high twirids at the earth!s surface will cause large amounts of 3.78 The Overall blast effect due to the dirt,- dust, .0-d other particles to be-sucked air shock from a surface bqrst will be less thez,ball ,of fire rises; (See Figurh. than that from an air burst for weapons of equivalent yield. For orie thing, part of the energy of the bomb is used up in vapor- a surface burst will be similar to that in an izing materials on the surface and in air burst. However, if the low level nuclear forming a crater. In addition, up to 15 explosion occurred,in a more or less built- percent of the energy may go into ground up area, the structures through which it shock. The main point, howevekr, is that passed would serve to reduce, even thou* because the bomb explodes close to thethey would not coinpletely shield, the earth's surface, the 6verpressure neat gamma radiation. For practical Inaposes, ground zero will be much greater than for however, it would be advisable to treat an air burst, but it will fall Off more rap-these two types of burst as the same as far idly with increasing diitance from ground as initial nuclear radiation is concerned. zero,.

3.79 As a result, energy will be wasted RESIDUAL NUCLEAR RADIATION t on targets close to ground zero which could have been destroyed by much lower 3:82 With respect to residual radioac- overpressures. At the same time, the over- tivity, -a nuclear explosion at a low level pressures a some distance away will be would produce effects somewhat similar to -too low to cae any considerable damage. a subsurface burst. That is, a considerable In other words, there will be an "over- amount of dirt and ot et debris or water, destruction" of neay surface targets and would be hurled into he air, and upon an "under-destruction" of those further descendrig, it might pr d cea base surge away. The energy that has gone to produce (highly radioactive clouof dust or vapor) ground shock may contribute, however, to which will be contaminated partly from the destrzation of underground targets pro- the condensation on the ground of the tected from the air blast such as missile nuclear reaction prOducts froin the ball-of launching sites. Figure 3.43c, (and its leg- fire, partly from the fallout of heavier end), will provide additional specific infor- pieces, and partly from radioactivity in- mation on surface bursts. ducdd by neutrons.. THERMAL RADIATION CHARACTERISTICS OF A SUBSURFACE BURST 3.80 The general characteristics of the thermal radiation from a nuclear detona- 3.83 When a nuclear bomb is exploded - tion at the surface will be essentially the under the ground, a ball of fire is formed Same as for an air burst, described previ- consisting of extremely hot gases at high. ously. As stated earlier, if evasive action pressures, including vaporized earth and can be taken within a second or so, part of bomb residue. If the detonation occurs at the heat radiation may be ayoided. ' not too great a depth, the fireball may be seen as it breaks through the surface, INITIAL NUCLEAR RADIATION before it is obscured by clouds of dirt, and dust. As the gases are released, they carry.. 3.81 The initial nucleat radiation from up with thetS into the air large quantities

SHOCK FRONT

DIRT COLUMN

0 0.5 1.0

FIGURE 3.83a.Chpnologica1 developmentof a 100-KT shallow underground burst: 2.0 seconds after detona-

-45 , . - 1 1 1 1 MI LESI - 1.5 2.0 0- 0.5 4.0 4 noun 8.83b.Chronological development of100-KT a shallow underground burst: 9.0 secofidsafter detonation.

CLOUD NUCLEAR RADIAT1ON

THROWOUT

BASE SURGE FORMING

MILES. o a 2.0, Fromm 3.83e.--:Chronologleal development of a100-KT shallow underground burst: 45 see inds afterr detonation.

CLOUD

NUCLEAR,RAD ATION 41

bASE -SURdE COL

1 1 2.0 0.5 . 1.0 /1.5 . i irrauszafiad.--Chrenological development of a 1 KTa4Iillow underground burst: 4.minutes after detonation. - .. ,.

_ ,

.of eartht roele",-and debrisin fhe :form of a the surface Sn and, the cooling is so cylindrieal cojumn..The chronological '1 . devel- rapid that the erature. drops-alinost. opment of some of the phenomena associ- imjnediately t ated with n underground explosion, int where, there is-no. kay- further appreciable emissiono hermal, ing an energy yield. of 100 kyotorts,is adiation. It follows, therefore, tha"b4nan represented by Figures 3.83ato 3.$3d. 4 underground nuclearexplosion the her- 3.84 , It is estimated from:testsmade in Nevada that, if zeal radiatibn can be ignoredas fara-its a 1-megaton bomb were effects on persodnel andas a soCrce o fire dropped from the air and penetratedun- are toncerned. . ris . L derground in sandy-soil toa depth of 50 3 88 Itprobabie, to,at most of the .., feet before exploding, the resulting crater neIiIons andgamma rays liberated 0% wotild be about 300 feef deep anenearly 1,400 feet across: This,Aeans Withia shorttime of thelpitiation of the Cr that approxi- ',expl eiwn Will also be Ab's9rbed mately 10 million tong ot!soil. androck by the would be hurled upward from the earth. But, when the fir bailreaches the earth's sunfeleand the gasesre expelled; the surface. The volume of thecrater AO the gamma rays (and beta mass of material thrown up by the force of rticles) from. t fission products willre ent a. form of the explosion will increase roughlyin pro- 'initial nuclear tadiation. portion to the energy of the bomb.As they addition, the descend to earth, the fill.r radiation fromellission (andnutron- artieles of soil induced radiartive) products preseitt may initiate a base surges shown in in Figure 3.83d. the cloud stein, radioactive clfflid, and IDase ., surge, all three otwhich are formed within ..../ . a few seconds of the burst, Will contribute. o AIR BLAST A D GROUND SHOC to the initial effects. 3.85 The ya id expansion of thebu ble 3.89 However, the fallout fromthe of hot, high-pr ssure k.ases formedin t e cloud and the base surgeare also resonsi- underground urst initiatesa shock wave Ne the residual nuclear radiation. For in the earth. Its/effectsare iomewhae a subsurface burst, it is thus less meaning-, similar to those of ar earthquakeof mod- ful to make a sharp distinction.between , erate intensity, 9 xcept that the disturb- initial and ridual radiation, suchas is ance originates airly near the surface in- done in t é of an air burat. The inidal , .stead of at a gre t depth. The differencein nuc radiation merges /continuously depth of origin means that thepressures,into those which ire, produce:Iover a pe- in the underground a hockwave caused byyiod of time following the'nuclear explo- t a nuclear bomb probably fall off moie rap- sion. idly with distance han do thosedue 'to earthquake waves. HIGH ALTITUDE BURSTS 3.86 Part of the energy froman Under- giound- nuclear explosionappears as a 3.90 For nuclear detinations'at heights blast wave in the air. The fraction, ofthe up to about 190,000 feet the .density of air is such that the distribution of 'the explo- ../ energy imparted to the air in the form of blast depends primarily upon the depth ofsion energy remains almost unchanged, the burst. The greater the penetrationof approximating that described foran air the bomb before detonationoccurs, the burst, e.g., about 45 to 55 percent (ofthe smaller is the proportion of the shocken- fission energy) appearsas blast and shock, ergy that escapes into the air. and 30 to 40 percent is ihceivedas thermal ,radiation. . THERMAL AND NUCLEAR RADIATION 3.91 At greater altitude's, this distribution begins to ,change noticeably within- 3.87Essentially all,th

-between air bursts andhigh-altitude bursta. as shown in the upper portion of Figure 3.95-. The lower portion ofthe diagram 3.92 There is, ofcourse, no sharp shows some common EMPenergy collec- change in behavior at thiselevation, and tors. Sufficient energy van be collected by so the definition of a high-altitude burstas these means to cause damageto attached being at a height abofe100,000 feet is electrical and electronic equipment. somewhat arbitrary. Althoughthere is a 3.96In a surface cr near-surface burst progressive decline in theblast energy the relevant EMP enetgies with increasing height of burst are generally above 100,- well within the blast and thermaldamage 000 feet, the proportion ofthe explosion energy received as effective thermal areas close to the point of nuclear detona- ra- tion and thus covera relatively small geo- diation on the ground doesnot at first graphical area. change appreciably. This isdue to the interaction of the primary thermal 3.97 By contrast, ifa nuclear weapon is radia- detonated high above the earth's tion With the surrounding airand its sub- atmos- sequent emission in a different phere, the X-rays andgamma rays emit- *spectral ted downward from the explosion region. At still higher altitudes,the effec- will be tive thermal radiation absorbed in a big "pancake" layerof the received on the atmosphere between .12,/2 and 25 ground decreases and ii, infact, less than miles at an equal distance froman air burst of above the earth's surface,as s'hown in the same total yield. Figure 3.97. Thegamma energy is converted into lower-frequencyelectromag- 3.93 One aspect ofa high-altitude burst netic energy in this interaction regionand that has received increasedattention in propagated downward to the earth'ssur- recent years is the electromagneticpulse face as a very brief but powWulelectrom- (EMP). Its iinplicationswere first noted agnetic pulse. Tlie strength of thispulse during an experimentalhigh-altitude on the ground is much thesame.as ip the burst_oxer Johnson Island inthe Pacific moderate damage area of a,surfaceburst. Ocean in 1962 when stieetlight 'failures However, very largeareas, otherwise un- and cominunicationsdisruptions occurred damaged, can be affected by the highalti- on Oahu, 750 miles awdy. Inan era of tude detonation,as the lateral extent of intercontinental ballisticmissile systems, the "interaction region" is generallylim- and defenses against thosemissiles, the ited only by the c(gvature of theearth. possibility of ,a high=altitu-aeburst in a nuclear attack becomes 3.98 The extent of that damagecan be very real. seen by considering a typical high-altitude 3.94 Put simply, the electromagnetic burst over Omaha, Nebraskaas shown in pulse is, that portion of theelectromag- Figure 3.98. Within the circlepassing netid spectrum (Figure2.42) in the me- through Dallas, Texas the EMPhazard * dium to low frequencyrange extending would be the greatest. Theouter circle roughly from the frequenciesused in ra- shows that there is potentialdamage from dar and TV down to thoseused in electric EMP effects over the wholearea of the power. Since most of the energ,y isra- United States. diated in the frequency bands commonly 3.99 EMP can cause two kinds qf dsed for radio and TVcommunications, it dam- is sometimes called "radio-flash."It is dif- age. First, functional damage that would ferentiated from the thermalradiation require replacement ofa component or "pulse" that produce heat and piece of equipment. Examples wouldbe light and the burnout of a radio receiver "front the initial radiation ',!.1Tlse" ofgamma and end" X-r ys, or the blowing of a fuse. Second,operational upset of equipment suchas opening 3. There is concern about EMP be- of circuit breakersor erasure of a portion cause he-energy in the pulse can be col- of the memory of a computer. lecteçY and concentrated, muchas the 3.100 Exberiments have shownthat CD sun's rays can be focused to prancea fire, raciiation detectionequipment is not sus- 49 * '4: 1 INT:ERACTION, .41 .g. fI I ; I 'I ;1" I .' I I 1 I I I I I I r 1 -EM FIELDS I 1

EARTH

EM energy Is picked up by long conductor and delivered to sonsItIveeauIpment. EMP.ENERGY FROM HIGJ-I ALTITUDE BURST, - r

From: Survive, November-December 1969

4:IGURE 3.97.---EMP energy from high altitude burst. EIVIRGIIIDUND COVERAGE-Of HIGHALTITUDE EIUR4T-S

Source': 'Defense Nuc lelr Agency.

FIMME 848,-=EMErground'cOver,age of high altitude bursta -Optible-to_ direct daitagè norare hand HIGH-ALTITUDE BURST 5' held Pitigent BantilvalldetalkieS. or FM radio -receiVere. The' vulnerability of indi- LIGET: Very intense. iiduit..electrical or electroniC eiluipment HEAT: Moderate, decreases with increas- cart -vary itreatly, Transistor s.. 84.4_ inipro- ing burst altitude. r- jviire[dicides, for exaMPle,, are relatively INMAL NUCLEAR EADIATION: Negligible. thah vacuuM tubes or bleötiieniOtois. SHOCK: Negligible. .3.101. ttig EMP:threat and protective Aut BLART: Small on the ground, deereas- measures for civil preparedness. related ing with increasing burst altitude. ,equipinent are available in EARLY FALLOUT: None.. tectinical phblicationa of DCPA. E Mer- SUMMARY: The most significant effect will -gency oPeritting, Centers; broadcast radio be flash- blindness over a very large ind:TV,-telephOne and electric power sys- area; eye burns will occur in persons thins and; public safety radio are'some of looking directly at the explosion. Other -the-Area's-of concern. effects will be relatively unimportant. 3.102Listed- beloW are seven anti-EMP actiOns that could be applicable to local AIR BURST civil preparedness operations. 1. ,Maintain a supply of spare parts.. LIGHT: Fairly intense, but much less than 2. Bhift to emergency power at the earli- .for high-altitude burst. gst possible time. HEAT: Intense_ out to considerable dis- a. Rely on telephone contact during tances. threat period' so long as it remains INITIAL NUCLEAR AADIATION: Intense, but operational. generally hazardous out to shorter dis- 4. If radio_ coMmUnication is essential , tance -than heat dining-threat period, use only one SHoCH: Negligible except for vèy low air" system at a tini6. Disconnect all other bursts. systems from antennas, cables, and AHISLASTL Coriaiderable out to dstances power.. . similar to heat effects:% "6: Disconnect radio base stations, when EARLY FALLOUT: Negligible. not-in use from antennas and power _ line. SUMMARY: Blast will cause considerable g.Plan for mobileto-mobile backup com- Structural damage; burns to exposed munications. skin, are possible over a large 'area and I. Design emergericy operating plans so e5T effecti over a "still larger area; initial nuclear radiation Willhe:a hazardet --:that-pperationa will adegfade_grace- fully if coMmunications are lost: elbser clistanOei; bift..tne early Eillouf hazard will-be negligible.

_SUMMARY-OF EFFECTS OF IlAiIOUS TYPE GROUND SURFACE BURST BURSTS., LIGHT: Less than for an air burst, but still MAP ,Some general conclusions cah.be appreciable. .OfferefineuMniary of the degree Or seyer- HEAT: Less than for an air burst, but ity.of the particular effeCts of the various significant. typea'of nuclear detonations. The ;various INITIAL NUCLEAR RADIATION: Less thin degrees are relative to, each -other for a for an air burst. glien,btirst tyPe, andiare best'inthrpreted in tenni of the descriptions given below. SHOCK: Will must damage within about three crater radii, but little beyond. , ; isonitharris repdMed from THE EFFECTS OF NUCLEAR WRAPO-NS:' *As modified by4.9S-3.102. =' AIR BLAST: Greater than foran air burst surface burst are similar' to those fora at close-in distances' but considerably ground surface burst, except that the less atifarther distafices. effect of the shock wave in water will EARLY FALLOUT: May.be considerable(for extend farther than ground shock. In a high-yield weapon) and extendover a addition, water wavescan cause damage large area. on a nearby shop by the force of the waves and by inundation. SUMMARY: Except in the regionclose to ground zero, where destruction would SHALLOW UNDERGROUND BURST be virtually complete, the effectsof blast, thermal radiation, and initialnu- LIGHT, 'HEAT, AND INITIAL NUCLEAR RA- clear radiation will be less extensive DIATION: Less than for a water surface than for an air burst; hoWever, early burst, depending upon how much of the fallout may be a very serious hazard fireball breaks through the surface. over a large area which is unaffected by SHOCK: Ground shock will cause damage blast, etc. within about three crater radii, but little beyond. SHALLOW UNDERWATER BURST AIR BLAST: Less thanforiasurface burst, LIGHT, HEAT, AND INITIALNUCLEAR RA- depending on the depth of burst. DIATION: Less than. for a ground surface EmtLY ,FALLOUT: May be considerable, if burst, depending on theextent to which thi-apth of burst is not too large, and the fireball breaks through thesurface. in addition there may be a highly radio- SHOCK: Water shock Will extendfarther active base surge. than a water surface burst. . SUMMARY: Light, heat, initial nuclearra- AmBLAST: Less than for surface burst, diation, and blast effects will be less depending upon depth of burst. than for .a surface burst; early fallout EARLY FALLOUT: May beconsiderable, if can be significant, but-at distances not the depth of bhrst is nottoo large, and too far from the explosion the radioac- in additioh theremay be a highly radio- tive base surge will be an important active base surge. 41. hazard. Water waves can alsocause damage, as in the case of a watersur- 1.1MMARY: Light, heat, and initialnuclear face burst. radiation will be less than fora ground surface burst; early falloutcan jpe sig- CONFINED SUBSURFACEBURST nificant, and at distances mot too far LIGHT, HEAT, AND INITIAL from the e3Icplosion the basesurge will NUCLEAR RA-, be an important hazard. DIATION: Negligible ornone. . SHOCK': Severefrespecially.at fairly4close WATER SURFACE BURST distances from the burst point. LIGHT: Somewhat more intense than fora AIR BLAST: Negligibleor none. ground surface burst. SUMMARY: If the burst doesnot penetrate HEAT: Similar to ground surface burst. the surface, either "of the groundor INITIAL NUCLEAR RADIATION: Similarto water, the only hazai-d will be 'from ground surface burst. ground or water shock. No othereffects -will be significant. SHOCK: Water shock cancause damage to ships and underwater structures toa REFERENCES considerable distance. AIR BLAST: Similar to ground surface The Effects of NuclearWeapons.Glas- stone, Samuel,:1964. EMP Threat ahd EARLY FALLOUT: May be considerable. Protective Measures, DOD/bCD, TR-61,August 1970. SUMMARY: The general effectsof a water RCPA Attack EnvironmentManual. C.) 0 SS CHAPTER 4

NUCLEAR RADIATION MEASUREMENT

Since we cannot hear, see, smell, tasteor 4.2 At the present time, nuclear radia- feel nuclear`radiation from the fallout,we tion detection instruments are widely used must relir entirely upon instruments in in industry and research. X-ray films and order to DETECT its presence and MEAS- Geiger counters are.items of everyday URE the degree of danger. In this chap- conversation. In this diapter we will dis- ter, then, we will look at: cuss the principles and theory of operation HOW nuclear radiation may be de- of many nuclear radiation detection in- tected struments, or radiological instruments as we will refer to them. These instruments HOW nuclear radiation may be are very similar to other types of elec- measured tronic equipment. Their main diskinguish- WHAT instruments exist to do the de- ing characteristic is their ability to re- tecting and-the measuring spond to nuclean radiation. HOW do instruments operate 4.3 The term DETECTION is used in WHY do we need different types of this text to inclue only the indication of instruments the presence of nuclear radiation. The term MEASUREMENT will be reserved WHAT are the units we use to meas- for both the detection and quantitative ure nuclear radiation estimation of the amount of nuclear radiation present. , INTRODUCTION

4.1 Man is aware of his environment PRINCIPLES OF RADIATION DETECTION through his senses. He cansee, smell, taste, hear and feel. Yet, none of these 4.4Radiological instruments detect the senses will make him aware of the pies: interaction of radiation with some type of ence of nuclear radiation. This situation is matter. Th,e different principles of radia- not really unusual. In fact it is Jike his iion detectionare characterized ,by the ,i,nability to respond direptly to thpwaves nature of theinteraction of the radiation of ultraviolet light and radar, television,,With the detecting or sensing element. or radio transmission. For example, a man Several types operate by virtue of the may receive a serious sunburn due to ov- ionization which is produced in them by erexposure to 'the sun's ultraviolet rays, The passage of charged particles. In other yet his first indication of over-exposure detectors, excitation and sometimes molec- may come Several hours later when he ular disassociation play important roles. feels pain. In this Situation hewas not 4.5During the 18.90's, Henri Becquerel , awareof the ultraviolet rays during the found that photographic plates, when exposure period; however, in a sense, he placed in proximity toores or compounds did detect the ultraviolet light indirectly:6f uranium, were affected inthe same 'since certainlY wotild be aware, ofa manner as if they had been exposed to painful sunburn. Similarly, since man 011.7_,light.,This occurred even when the platps !riot rely- on Ilia leiiies le detect nhcrear Were prOtected by sufficient coveringto radiation he must rely on some secondary assure that the strongest light could not means such as instrumentation. I affect them:This date marked the discov- GI SS ery of radioactivity, and today this princi- the current is measured. Since the light ple is still used to detect and measure the intensity and the resulting electrical cur- product of radioactivity, NUCLEAR RA- rent are proportional to the rate ,of radia- DIATION. tion exposure, the instrument can becali- 4.6 The photographic detection tech- brated to read radiation exposure rates. nique is relatively simple. As a charged 4.8 A third principle for detecting ra- particle passes through a photographic diation is based on the fact that many emulsion, it will generally cause change% substance's' undergo chemical changes which will result in a blackening of the when exposed to radiation. This is particu- emulsion when the film is developed. The larly true of chemicals in aqueous solu- photographic emulsion consists of finely tions where the decomposition of the divided crystals of a silver halide, usually water itself contributes to the reaction. If Silver bromide, suspended in gelatin and the extent of the chemical change can be spread evenly on a glass, cellulose, or pa- conveniently measured, tite reaction can per base. When charged particles strike be used for measuring radiation. There the emulsion, some sort of ionization not are several chemical reactions which may well understood takes place. This local dis- be utilized in this manner. One of the first turbance of the electrons in thesrystals of used was the liberation of acid from a silver bromide creates a latent image chlorinated hydrocarbon such as chloro- which is invisible to the eye when formed, form. Chloroform, water, and an indicator but which can be developed later by chem- dye are sealed into a glass tube. As radia- ical action. The chemical developer acts as tion penetrates thi tube, hydrochloric acid a reducing agent to deposit metallic silver is liberated from the chloroform. The liber- only at those points in the, emulsion where ation of this acid reduces the pH of the radiation interacted- and in proportion to solution and causes a distinctive color the amount of radiation which acted on change in the-dissolved indicator. The ex- the ,silver salt. The amount of blackening tent of the color change is an estimatt of o9, the film is a function of several factors: the radiation exposure of the tube. the time of exposure, the intensity of the 4.9Becquerel's discovery that gases exposure, the sensitivity of the film, and become electrical conductors as a result of the chemical prqesses of development. By exposure to radiation provides us with a rigidly controlling these factors, the black- fourth means of detecting and measuring ening of the film can be Made proportional radiation. When a high-speed particle or a to the radiation exposure. photon passes through a gas, it may cause 4.7 A second method of detecting radia- the removal of an electron from a neutral tion was again first employed by Bec- atom or molecule causing the formation of querel and Rutherford in their early work an ion pair. This process of ionization in a with radioactive substances. Certain ma- gas is the basic phenomenon in allEN- terials will produce small flashes of visible CLOSED GAS VOLUME INSTRUMENTS.The elec- light when struck by alpha, beta, or tron produced may have rather high ener- gamma radiation. These flashes are called gies and may produce more ionization in scintillations. The mechanism of formation the gas until its energy is expended and it of these scintillations is very complex but is efinally captured by an oppositeV essentially it involves the initial formation charged ion. If two oppositely charged cqi.- of higher energy (or excited) electronic lecting electrodes are introduced into the states of molecules (or atoms) hi certain gas filled chamber, the ion pairs will mi- materials. Some of the absorbed energy grate to their respective electrodes. NegiN, which has been derived directly or indi- tive ions will move toward the positively rectly from the incident radiation will be charged electrode and the positive ions emitted in a very_ short tVrie as photons of toward the negatively charged one. When visible or ultraviolet likht. These light the ions reach the electrodes, they will be r: photons are-then converted into an electri- neutralized, resulting in a reduction of the cal current by a photomultiplier tube and arge on the electrodes. In one type .of . 56 instrument this loss in charge ia usedas a of energy liberated in the absorbingmate- measure of the radiation exposure. In.an- rial, and theBIOLOGICAL DOSEis a meature other type, batteries are used to replace of the biological effect ofa particular ra- the charge on the electrodes resultingin a diation absorbed byan individual. How- current flow in the external circuit. Within ever, it is also important to emphasize certain limits, this ionization current will that the ultimate objective for measuring be proportional to the radiationexposure an exposure to radiation is to relate that rate. to a certain biological response of theex- 4.10 In addition to the four principles posed individual. discussed above, there are several other principles which .may be utilized for the detection of radiation, but to date these uNrrs OF RADIATION MEASUREMENT have not been as widely used. 4.13 As discussed in Chapter 2,the roentgen is the unit of radiationexposure. TYPES OF RADIOLOGICAL INSTRUMENTS This unit is basedon the effect of X or gamma radiations on the air through 411 In the development of radiological'which they pass. It is definedas that instruments, the choice of detector isan quantity of X or gamma radiation such important factor. An equally important that the associated corpuscular eniission factor in their design is thetype ofinfor- per cubic centimeter of dry atmospheric mation required by theuser. Normally air at 00 centigrade and 760mm of mer- this information falls into two categories: cury produces, in air, ions carryingone the measurement of total accumulatedex- electrostatic unit of Charge of either sign 'posure to radiation, and the instantaneous (2.083 x 106 ion Pairs/cc). Since this unitis rate of exposure. The first isreferred to as rather large for measuring peacetimein- anEXPOSURE MEASUREMENTand the second,, as an cupational exposures, the milliroentgen, EXPOSURERATEMEASUREMENT.As an which is equivalent to 1/1000th ofa roent- example of a situation in which bothtypes gen, is frequently used for measuring of information are required, considerthe small exposures. Sincedosimeters meas- followink. An area is contaminated with ure exposure, they measure in fallout. A person is required ROENTGENS to enter the orMILLIROENTGENS,while survey meters, area and not eiCeed an" exposure of 25 whiCh measure/exposure rates, roentgens. This situation requires measure in an in- ROENTGENSper hour orMILUROENTGENSper strument which will measure the totalac- hour. It is importarit to note that theroent- cumulated radiation exposure duringthe gen applies only to the measurement of X period of stay in the contaminatedarea. or gamma radiation, and does not apply to Instruments_ designed to provide such the measwement- of alphaor beta. radia- measurements are calledDOSIMETERS. tion. Next, aasume that the operation to be 4.14 These units ofexposure and expo- performed will require two hours to-corn- sure rate are related by a time factor Plete; In-order'to deterMine ifentry into the area is practical, jt is analogous to the relationship betweento- necessary to tal distance traveled and speed. Forexam- -know the instantaneous rate ofexposure fa which the ple, the total distance from Battle Creek, person would be exposed in Michigan, to Detroit, Michigan, is approxi- the contaminated. area. Instrumentsde- mately 120 miles. A person leaving Battle signed to measure exposure rateare called SURVEY AFTERS. Creek and averaging 40 miles per'hour would- require three hours to travelto 4:12It is iinportant to emphasize thatDetroit. Similarly, if aperson -entered a radiologieal instruments measureexpo- radioactive contaminated area where the sures awd Dot abSorbed dr biological doses. exposure rate was 40 roentgens per hour StithEXPOSUREis a Measure of the and remained for three hours, his total strengt14" of the radiationfield, while the accumulated exposure would be 120 roent- ABSORBED DOSEis a measure of the 6notintrgens. This, of course, assumes that the 40

0,7 . 'roentgens per hour exposure rate re- - Mained constant. Just as it is ,difficult to .^.:maintain a speed of 40 miles per hOur, so nfight..it be difficult 'to maintain a radia- tiOn field of 40 roentgens per hour, since -radioactive materials decay according to fixed natural laws. This decay will cause the 40 roentgens per hour exposure rate to *crease with time. However, if the radio:- (active material has a relatively long half- life, the decrease in exposure rate during a three-hour period may be negligible. (With fallout, especially in the early hours after detonation, the decrease in exposure rate will be appreciable during a threeAlour period.)

DOSIMETERS

4.15 As indicated above, it is necessary FIGURE 4.16b.Radiation effect on charged in emergency operations to provide an in- electroscope. strument'capable of measuring an individual's total exposure to radiation. It is clear, from the definition of the roentgen that simeters, consider a foil leaf electroscope the measurement of ionization in air is (Figure 4.16a) consisting of an outside basic to the determination- of radiation metal shell iii which issmouhted an exter- exposure. In Civil Preparedness an ioniza- nally projecting electrode. An insulator tion chamber employing the principle of such as amber or sulfur insulates the elec- enclosed gas volume has proved most sat- trode from the outside case. Two narrow isfactory for exposure measurement. strips of a, thin foil' are cemented to the 4.16 To understandithe operation. of do- enclosed stem of the electrode to form the mOving pit of the-electroscope. Normally,

windows in the ease serve for viewing the 4 7:ELEC1RODE foil leaves. If an electrical charge is applied to the externally projecting electrode, it is transferred through the electrode to the foil leaves. Because Of the CASE mutual repulsion of like chargeS, the: lepAres -will immediately repel each other FOIL LEAVES until the electrical repulsion is just counter-balanced by the gravitational force tending to bring therd back together: If the air in the 'enclosed chamber is ionized bir radiation(Figure 4.16b), it becomes an electrical conductor and. this permits

thecharge. ,on the leaves to leak away. Since the electrical charge is reduced, the Mutual repulsion of the leaves is reduced and they assume a position clOsertO- gçther. This same principle is basic to the oPeration of dosimeters. The electrostatic self-indicating dosimeter used in Civil Pre- paredness is nothing more than a sophisti- FIGURE 4.16a.ohArged electroscope. cated electroscope. , FIGURE 4.17.Constrnction principles-ofan electrottatic self-indicating dosimeter. 4.17 The dosimeter consists of a quartz suspension. Only when the dosimeter is fiber electrometer suspension mounted in- placed oi ?. a dosimeter charger and the side an ionization chainber (Figure 4.17). bellows depressed can contact be made 'The electrometer suSpension is supportedLbetween the rod and electrometer. This, by meani of a highly insUlated material arrangement provides a very high electri- inside an ,electrically conducting cylinder. cal, resistance, and the hermetic sealing The enclosed air volume ,aurrounding the allowed by such construction makes the electrometer suspension it the ienization dosimeter readings essentially _indeisendr chamber or the radiation senSitive compo- ent of huMidity and pressure changes, nent-of the instrnment. The indidating eleinentiaalive micron (I/5006 in.) quartz ,4.20 tOdUseq,con the quarti fiber is a 75 fiher -Which is part ,ot,:the -electrometer to 126 poWer MicroSoope which magnifies suspension, The quartz fihorhas. an electr- the iniake of the qUartz fiber ta that it is ically canducting coating evaporate d. on its viiible. the microsco-pe consists etone ob- .surface -and has thelltaine forrn:factor as jective lens; one eyepiece tens, and con- the metal frame of .the, electronieter. tn, tains a,scale or reticle at the real imageof most dosimeters both frame and fiber are the. q:iiartz ,fiber. The scale is graduatedin irithe'shape of a horseshoe,the fiberheing roefitgent or milliroentgins depending on attached to two offsett an the lower ex- therange.Of the inttruigent.: trenntiet of thefraine. 4.21 in preparation for exposure to ;Ilk 4:18 The dosimeter contains anlectri- diation, the .dosiineter is thiNei, to4bout ca with!,the,eleeire- 100 to 115 volt'a to h;riniliki image !:;f-the .rnetev pspensfen and the, chamber Wall. quarti fiher te Zere on the scale. (Pigure The range of the dosirneter is determined 4.21). In charging the dosimeter, an exter- ttie ti'ae of the: capac,or, the charnber nal source of electrical ,pgwer islised, the 'vOluine; the sensitiviti of the eleCtrOrrie: ionization Chamber is held at,grod pa- tr,the pressure inside the _ionization tential and the metal frame and fiber, of Chamber 'and the optical sYStein. Only the electrometer assume the other ex- prestige and capacitance Variation offer a* treme of the Voltaie difference. The fiber Wide ,telection of ranges. Therefore, the is repelled from thesframesince both are fitnCtion of the electriCal 'Capacitor is to_at the same potential. The pesition of the charige the.;range of the ,dosimeter. :How- quartz Ober will then yary with the poten- eVer; for a *0014 dosiineter, the rance tial difference. This variance is linear for Will:be fixed hy the seleetion of thetapaci- the voltage range, covered by the scale. tor at the, time ()Ott mannfacture. -When the inttruinent readi.fUll 'kale, the

. 4.19 Thech arging. switch- assembly con- potential difference is not zero but usually

sista ofa hellows and- a contact, rod,, which seine. intermediate voltage between 76 and ;riorMaillyitolatedfroM the electrometer ,125 !Olt& , (59. FIGURE 4.21.Zero dosimeter reading: FIGURE 4.22b.-80 R dosimeter reading. 4.22 As the dosimeter is exposedto Xhairline image of the quartz fiber (Figure or gaMma radiation, the photons will; in- 4.22b). teract with the wall ,of-the ionizatiOn The movement of the fiber isa function chamber producing secondary .electronsof the total amount of radiation to which 4:22a).. These electrons enter the the dosimeter is exposed, regardlees of the neneitive volume of the dosimeter and:ion- rate -of exposure to radiation. .- izet e-,41r. molecules. Under theinfluente .Of the-electrical field in theehamber, 4.23If the dosimeter reading iszero at the,the start of a period, the -ierijiairs Migrate to the_ electrode ofopp o- exposure may be -eharge and are neutralized: Thisread directly from the dosimeter. How- ;:ga0agii :a Proportionate discharge of -the ever, any initial dosimeter reading must' CaPacifor.isystetn and decreases thepoten- be subtracted from the final readingto tial :between the electrrometer obtain a correct indication of the total and: the ehatriber wali. the.quartz fiber exposure. For example, if a dosimeter reads 10 rems at the start ofa period and 04:y Ogisiimetaleiv position corresponding reads 55 rems at the end, the -tat)* 'new, potential 'difference:Thisis exposure reflected bit ini:-upleale movementof the during the period is 45 reins. Performance 'characteristics of dosimeterswill be discussed in the next chapter. DOSIMETER. CHARGERS : ..,4.24The design of ,dosinigter ihargerti hag progressed to the point that thelater models- all use transistorized, circuitsto provide the required charging voltage. Al- though some of the earliest Chargers were not transistoriieq, probably all future ones Will' b,e beCause of the ease of 'opera-

CHARGING CONTACT

an eledrostatic LIGHT SWITCH,OPiN tlesiineter. , FIGURE 4.25a.Initial condition. WOW SWITCH OPEN

DOSIMETER

wiltutz OLTAO Or- zip, you's, AwnwatitAKE tT.cIøG* I. FIGURE 4:254Simplified diagram cif !c CD V-750 . LIosimeter charger./ p,04:1T Siviitht 0_0,SED then reCtified by a diodeEu4i'potentielof 'FIGURE 4.r:h.Readingposion. 220 volts maximum is ailable at the charging.contact. A volta e dontrof iaused-- -CHA SWITCH C OSED to adjust. the output vo tage to the exact value required to 'brinthe dosiMeter to Zero. 4.26 The mechan of 'charging a do- 1401 simeter with this t pe of charger will be discussed in the nech4ter. IMETER

SURVEYMETER 4.27 ,Nr-d* cUssions ,in paragraph 4.11 established':additional requirement Air 1;14, azyinitrurrie t WhiCh-;would measure exposure rate, or' use in Stir:Toy Operalions; EIGHT SWITCH CLOSED This initment Wail meaiure the rate FIGURE 4.25e,Charging.position. of fOrma ion, of ion pairs rather than the total n,ber- that are Troduced_by radia ditelhe enclosed gas volume prin!. tion of the transistorized models an4 pro- cipleas again proved most satisfactory !ST-vil.Preparedness-uses. 4.26. In:the transistorized chargei, the 4 There are tWo types of Civil. Pre- eireuft,iati:Otvered by a sin* 1,5 volt bat- edness, exposure rate instrUments 40: "The eh-44ring contact lawshowp in its ich- depend on the .principle of, ele ctri cal 'lnitliii-coriditioii in Figure 4 25a When a ollectiOnot ions .(enclosed .gas -volume) for

4eSiMeter Is Placed On ther-okopq don- their -inieration.-The., Charaiteristics Of . 114 and, pressure is wlic4, the Iight eaCh depend mainly ,on the yoltage at ;a:Witch ,eloises and -the billb lights _(kigur which the enclosed gas volume is-oPerated. 4.25b). go*ever,in thii Iisitionthe doSi .To:understand their operation, it as neces- eterigiinhOt be Charged, sines the dOsi# sary teinvestigate the behavior of ions in *- charging switch is still open. so- an electrical field. A sYstem for investigat- tiOn4 'Pressnre must be 'apPlied' to lose ing this 'behavior is illustrated in Figure thilcisarit-ek(Fi-gtife-4,25eY. Alralisiii or 6S- 4-08. leCensiSts ofa chainber filled with Cilla4r cOnterts the ,direct CUrien froma air In, which, age.fixed two parallel metal 'light battery tO alternating current plates to act-as.electrodes. The electrodes Me:transformer cari "stup" the are connected to-a batte,ry in such a way VOltage 1(1.5 yoitri) to e yoltagtthat the voltage can be increased steadily d:bY the deSimetét. e current is from zero to:several-hundred volts. A me- curve in Figure 4.29 Will result. For 'convenience, the curve is diVidento fiv,e regions, A, B, C, D and E. 4.30 ,When the Nioltage applied toar electrodes is, low, the eledhcal accelerating force is small.. Thus, s the ions move rather slowlY and have sufficient time to recombine with other iqns of opposite sign in the vicinity. The size of the pulse measured will be leis than if-all of the ion pairs foimed succeeded in reaching the elec- , trodes.-Asthe applied.yoltage is increased, FIGURE4.28rCircuit for measuring the behavior of the ions fravel faster. Their chances of ions in an electrical field: recombination are lessened' and' the pulse .size inereaSes. Finally, as the applied volt- ter is placed in.ttie circuit to measure the age is ,increased sufficiently, all 'of the size of the electrical current produced. primary ion pairs will be collected at the 4.29Normally, the air rn the ioniiation electrodes. This voltage is referied to as chamber will not conduct electricity and the saturation voltage. 'As theelectrode no current will fldw in the external circuit. voltage increases above this point, no in- If a single ionizing radiation enters the creak in the size of current pulse is imme- chamber when a small difference of poten- diately experienced since all of the pri- tial is appliedqo the electrodes, a,number mary ion pairi have been collected. There- of ion pairi _will be produced .which will fore, the pulse size remains relatively con- move to7 the oppositely charged electrode. stant throughout region B of the curve in When these itarges collect, a current Figure,4.29.,The actual voltage range over pulse will be measured by t,he meter in the which the pulse size is constant depends ...external circuit. If. a _constant source of on ,many factors, which include the gas gamma radiation is used and the size ofused in the Chamber, the pressure of the he current .ptilse is plated against thegas, and tlie distance between the elec-- Voltage applied to the eleetrodes, the trodes. 4.31,Region B of the curves is referred AnomelmiTION CONTINUOUS DISeHARGE to as the ionization chamber region, and , IONIZATION CHANNER PROPORTIONAL 'instruments designed to operate in this GEIGER MULLER region are called ionization 'charmber in- A. struments. SinN batteries are Usually

.usdas the ,pP;pe, .0* PleOricALTPNYerjilir. _ ItAl5EF- instruments, this region is we4' adapted for their use. If the operating voltage for a particular ionization 'chamber is chosen at the upper end "of the plateau, the size of the electrical pulse, produced by radiation wilt not vary appreciably as the electrode voltage decrea'ses

cAmmA with both age and use of the batteries. RAXS-47 4.32, As the applied vblta e is increased .beyond the 'onization chamb r region; the size of thelIse is increased. n region C 0 of the curve, the increased electrical field 0 INCREASING VOLTAGE 4 ...- - -- causes tlie primary ions io gain sUfficient VOLTAGE APPUED ACROSS THE CHAMBER kinetic energy to sause secondary ioniza- FIGURE4.29--I'ulse size v. applied voltage for gamma tion of other atoms and molecules in the , radiation. gas. This secondary ionization leads to an inerease in the size of the pulse, which an electrometer tube and an indicating amounts to an internal amplification of meter. thop.ulsein the_enclosbd gas volume: This 4.361 The detectitig element of the in------iinTiplifiCatiOriliiereases with applied volt" strument is an hermetically sealed air- age aria remaing linear until 'an internal equivalent ionization chamber. It consists an...3plificatiOri factor of approximately 1,000 of a conducting cylindrical container of, is,obtained, Region C is theproportional . . plastic and:steel called the shell and a thin region, and instruments operating-in this conducting tlis-k, which is located in the region are called proportional counters. center of the shell, called the collector. No- Civil Preparedness instrumentsoper- These are respectively 'the positive and ate in this.range. negative electrodes and are insulated from preportionartekron, a large.-each other by an extrelifely hiih resist- number ot secondary ion pairsare pro- ance feed-thru insulator. A collecting volt- d.uced at only one point within theen- age 'is applied to these two chamber elec- Closed gas volume. However, when theap- trodes. plied voltage is increased further, thesec- ft --ondary ionizatidir occurs threughout the enclosed gas voltime. Therefore, since the amplification is so great in the Geiger Muller region, the size of the pulse is almost independent .of the number of ion. Thiii-produced:fihns,-pne initial ionizing event 'Occurring within-the_..enclosedgas -,-yoluinetwill=-initiate an-ELECTRON AVA- LANCHE (explained in paragraph. 4.46) 'Which 'will spread quickly throughout the entire tube: Instruments operating in this region will produce one large 'pulse for each ionizing event to' which the tube is subjected. Gas arriplification factors of the zerderof 100 million are common. r 4:34\- When the operatingVoltage ex- ,"ceeds. the Geiger Muller region, it.isso high that once ionizatpakes place in the gas, there is a continuous discharge of electricity so that it cannot, lie used for ibunting purposes. Theupper- end of the Geiger Muller region is marked by this- breakdown voltage. FIGURE 4.35.Simplaed eireuii diagram for a Civil Preparedhess ion chlaiber survey meter. OPERAVIONOF ION CHAMBER SURVEY METERS" 4.37 When the instrument is exposed to radiation, some of the energy of the radia- 4;35 The development of ionization tion field is absorbed within the walls of charnber=e44.rvey meters has alsopro- the ionization chamber. Asa regult, elec- gressed to"the point that, the later models trons are ejected Troin the wills into the- ,of -ionization chamber survey meters and air contained wiChirichamber. ther, As probably future models' will.use a modifi- these.electrons traverse the chamber, cation' of the eimplified schematic circuit they create a considerable amount of ioni- drawn in Figure 4.35. The. batik 'compo-, zation in the air. llider the influence of nents 'of this circuit are: (1) an ionizationthe electric Tield existing between the chaniber, sourceof electrical power, eh-amber electiedesz the ionsmove ,to the and---(3)-a measuring circuit consiking I` of electrode having the opposite charge; that r 63 t is,-positive ions move toward the collecting the radiation field, the Meter scale Can be disk and the negative ions toward the calibrated directly in roentgens per hour. shell. The arrival of these ions at the 4.41Prior to use for' measuring exTo- electrodes constitutes a current, the mag- sure rates, the static plate current must nitude of which is proportional to the numbe ,cancelled by the reverse filament cur- ber of ions collected. Since the number of rent to obtain 'zero meter current (zero ions created is proportional to the radia- reading). at zero radiation levels. Since it tion exposure rate, this ionization current will probably be necessary to zero the is prowortional to the exposure rate in the instrument in a radiation field, a section of ionization-chamber.-- the selector switchis used to short oht-the 4.38 A very small ionization current high-meg resistor and prevent any ioniza- (approximately 0.00095 microamperes at tion signal from being sented by the grid full scale on the most sensitive range) circuit. Thus, when the S-elector _switch flows through a " h-meg" resisr and (Figure 4.4T) is in the zero position, zero develops a measu able voltage. Thivolt- radiation conditions are duplicated and age is applied to the grid of a vacuumabe the zeroing process can be gccomplished calledan electrometer tube because it is even in tIle presence of a high radiation capable of measUring voltages at e field. tremely small current values. The electeo- meter tube. is connected as a triode. Its three elements are: (1) the filament which, when heated by current from the 1.5 volt battery, emits electrons, (2)-the grid, which controls the flow of these electrons according to the voltage applitd to it, and (3) the plate, whieh rpceives the elPctrons and passes them to the circuit in the form 'of a measurable current. 4.39 -.Measurement of the grid voltage of the electrometer tube is accomplished hy metering the change in plate current (Ip) directly. With-the-- selPctor switch in the zero position, the high-meg range re:: sistor.is removed from the grid circuit so -.that no signal voltage dan be developed as a result of any ionization chamber current. The quiescent value of the plate current is then exactly balanced by the buck- FIGURE 4.41,Se1ector switch and zero contro). ing-current (Q so that the resultant current through the meter is zero. Th.e buck: 4.42 The proper functioning of the ing current is adjusted breians of the measuring circuit including the batteries zero adjust potentioMeter. may be checked by turning the selector 4.40 When the selector switch is pladpd switch tethe circuit check position (Figure in a range position, one of the high-meg 4.41) and observing the meter readingl. In range resistors is reinstated into the grid this position, a predetermined voltage is circuit. The ,ionization current, therefore, impressed on the grid of the electrometer produces a positive 'signal voltage across tube to make the meter read approxi- this resistor, which in turn results in an mately full scale. Peterioration of any of increase in the plate current. Thus, the the components or batteries inthe circuit resultant current throUgh the miter is no will change this reading. Therefore, this longer zero and the meter measures-41wvoltage can be used to check the entiie increase in plate current. Since this circuit'at the exception of the ionizaton change isproportional to the magnitude of chamb high-meg resistor. 4.43 Allradiologicalinstruments duce further ionization. This cumulative should be calibrated prior to their iniial increase in ions is similar to a single rock field use and :pethdicalw thereafter._,_is precipitating an avalanche anct is, there, mgy beldone by -usingCalibrated source,_fore, often referred toasELECTRON AVA- of radioactive meter' l. If the instrument LANCHE.This avalanche may produce as does not read,proPerly when, placed ina many as 100 million_ other ion pairs for radiaticfn field"of knOWnexposure rate, the each initial ion pair produced in the cham- calibration control can be adjusted to give ber. the gas amplification factor of the the desired meter indication corréspond- tube under these conditions would be ingto the-knownfenwstire ratE; ab`out 100 million. 4.44Sensitiyity _of the instrument is -4,47__ Consider,,a Geiger tube filled with chi-nig-ed. by sWitehing high-meg resistors. a gas, frequently argon or neon, to an This is accomplished -by, the selector switch absolute pressure of ten centimeters of (Figure 4.41). On eachrange the meter mercury and exposed to a constant radia- xeading must \be multiplied by 0.1, 1, 10, tion intensity. If the number of pulse'sper and 100 to obtain the measuredexposure second occurring within the tube is plotted rate. againSt the voltage applied to the electrodes, a characteristic curve similar to OPERATION OF GEIGER COUNTERS Figure 4.47 is produced. This curve differs froni the curve in Figure 4.29 in that the 4.45 Geiger counter_operation is. based number _of _pulses. is ..plotted against the on the iönizatiori ot gases similar to the applied voltage rather than the size of the operation of ionization c_ha3nber_survey_pulse._Since$ under the_ operating condi- Trieref. rn theoniztiôn chaMber instru-tions placed on the tube, no gas amplifica- .ment, a very small current' is developed, tion occurs at low voltages, there isa amplified, and then measuredon a sensi- threshold below which no pulses will be, tive meter. The current is gThooth in chaArecorded. As theyoltage increases and the ----owtiber since the many ionizingevents Ire(gas amplification factor increases, the averaged. Geiger counters differ materi- number of pulses increases. At first, only ally in that the current flow is not smooththe most ionizing particles would be butit is.delivered in-surgesor pulses. counted and the weak ones lost. As the 4.46Geiger counters take advantage of voltage increases, however, practicallyev- the extreme gas amplification_ thatcan be ery particle entering the tube wil; be obined when' high accelerating voltages counted: When this conditionoccurs, The arepplied to the electrodes within the chamber. As ion pairs are formed in the gash they will move with increasing velocity toward the electrodes until eitherre- combination or collision with another air molecule occurs. The average distance be-' tween, successive collisions is referred to as the mean free.path. If the mean free path is small and tlie accelerating voltage relatively high, each ion will gain onlya small amount of energy between collisions. 'As the operating Pressure of .the Geiger tube is reduced, the mean free path is increased, causing the Lons' to gain addi- tionaLenergy between collisions. When the kinetic energy of the ions is' sufficient, they will cause secondary ionization. , APPLIED VOLTAGE These secondary-ions will Who be acCeler- FIGURE 4.41.---Number of pulsesvs. applied voltage - 'sited- by the-electrical field 'and will pro- for a Geiger tube. , 7-1 65 _ curve will flatten out. This is called the ble gas to the Geiger tube. Utilizing a Geiger plateau and it is desirable that it suitable electronic circuit, the operating be long and flat so that the counting rate voltage of the Geiger tube can be momen- does not depend strongly upon the applied tarily Teduced below the voltage required

voltage. Above the Geiger plateau voltage, for a self-perpetuating discharge as sooi. the tube goes into a continuous discharge as the avalanche begins. Other Geiger state and is not suited for counting pur- tubes, called self-quenched tubes, utilize a poses. small amount of alcohol or halogen gas to quench the discharge. In this ease, both 4.48 Avalanche formation will take argon and alcohol molecules fiarticipate in place in the vicinity of the central wire ofthe avalanche. As the positive ions mi- the Geiger tube, since here the eleckric grite to the electrode, the-argon ions hav- field is high and each electron on its way ing an ionization potential of 15.1 volts to the central wire acquires sufficient en- collide with alcohol molecules with an ioni- ergy for further ionization in each mean zation petential of 11:3 volts. This differ- free path. Thus, a large number of elec-ence in ionization potential causes the trons and positive ions will be formed near charge to he transferred to the alcohol the center wire in the first ,avalanche. The molecules and only these ions reach the electrons having a small mass and already electrode. As they approach the electrode, positioned close to the central wire willthey will pull electrons from the cylinder moye toward it with high velocities and wall. The energy of the excited states of will be completely collected in about one the alcohol molecules:will dgnssociate millionth of a second. The heavier positive other alcohol molecules rather than cause ions travel more slowly out to the nega- further ionization. The self-perpetuating tively charged cylinder. This causes a posi- discharge is prevented in this manner. tive ion cloud or space charge which reduces the electric field and stopsite ava- 4.50Since some of the quenching gas is lanche formation. In about one ten thou- disassociated at each discharge, the sup- sandth of a second, the positive ions or ply is constantly depleted and the Geiger - spacecharge will reach the cylinder wall. tube will havea limited useful life of about one billion counts. Halogens, particularly As a positive ion approaches very close to , the cylinder, it will pull an\ electron from chlorine and bromine, are currently being the cylinder-and he converted to a neutral used as .quenching gases in argon-filled molecule. Generally, the eleatron will 'counters and have some advantages over move into one of the upper energy levels ofthe alcohol-quenched tubes. Since the hal- the molecule resulting in an excited molec- ogen atoms will recombine after the disas- ular state. The electron will move to the sociation process, tubed filled with this gas ground state and in so doing may produce will Shave essentially an unlimited life. photons in the ultraviolet region which Halogens, however, are extremely reactive Will have sUfficient energy to liberate pho- gases and great care murt be exercised in toelectrons fiom the metal cylinder. With choosing electrode mterial.s. high tube voltages, this single photoelec- 4.51Figure 4.51 illustrates a typical tron will start a second avalanche andsimplified circuit diagram of a Geiger ,thus the entire process will be repeated-counter. The Geiger tube consists of a thin over and over again. Tbis-repeatid dis- cylindrical .shell *hich serves as the cath- -chitige must be stopied and the tube re- ode, a fine wire anode suspended along the stored to its initial condition if the tube is longitudinal.axis of the shell, and a small to be used to measure radiation. The proc- amount of a quenching gas. A potential of ess by which the tube Is prevented from approXimately 900 volts is applied between repeating the discharge is called que,uh-,the two electrodes. ing. 4.52 When radiation penetrates the tube, a gas molecule is ionized. The result- 4.49Quenching may be accomplished ing ion pair is accelerated toward the elec- either electronically or, by adding a suita-trodes by the electric field. Because of the .66 7° high accelerating voltages, thecreation of external circuit- The frequency of such additional ions is very rapid, thusproduc- pulses,is proportional to the strength of . ing a discharge (airalanche) inthe tube. the radiation field. The small amount of This llischarge results in- apullo in the7-hióèiijas intheint,eserves to stop each lischarge and restore the tube to its condition. 4.53 ke`pulse output from the Geiger tube is ambIified by conventional electronic means and then measured bya_ sensitive,,ineter,which-sinnS-up--the4adia--- tion effects in the form ofa reading in either-counts-per minute-or, in-the-case ofgamma rays, milliroentgens per hour. In, addition to the meter indication,most Geiger counters are provided with headphones which detect the pulses from the Geiger tube and producean audible click.

REFERENCES Sourcebook -on Atomic Energy las- stone, Samuel,D. Van Nostrand,19 Nutlear --RadiationPhysics.--Lapp, ,RalptrE: and Affi-vOroiviiidL.,' Pren- FIGURE 4.51.--Simpfifie4 circuit of a Geiger counter. tice-Hall, Inc., 1972.

7 3- 67 CHAPTER 5

RADIOLOGICAL EQUIPMENT

Having covered the theory of radiologi- DS_PA has developed several instruments cal instrumentation in the previous chap- thai, together, provide this.wide monitor- tgr, we are ready to move to the practical ing capability. These instruments fall into apects of detecting and measuringnu- two distinct-classes: ckar radiation. This means it is time fora Radiation survey meters for use by mon- look it the various types of radiological itoring personnel in.determining contami- equipment available and the different sit- nated areas and radiation exposure rates., qations in which each item would beap- Exposure measuring instrument( (do- plies!. In addition to learning whatwe simeters) needed by all Civil Preparedness have in the way of different 'pieces ofworkers such as fire fighters, fixst eiders, equipment, we will also be shown: rescue teams, and radiation monitors who WHAT the equipment can do have to perform their emergency duties in WHAT it cannot do contaminated areas. WHEN to uSe a particular piece of 5.3SURVEY METERSprovide the informa-, equipment tion required for -locating contaminatedareas and for estimating the degree of the HOWlo check it, operate it and care hazard. Since it would not be practical to - for it compute your total radiation exposure RADIOLOGICA*I. INSTRUMENT from survey meter measurements if the REQUIREMENts exposure rate varied during the exposure period,DOSIMETERSare also needed for re- 5.1 There is no exact equivalent ofcom- cording the total amount of an individual's bat experience upon which to base the exposure. Estimates of total exposure and requirements for Civil Preparednessra- related birological effects can be made on diological equipment. HoweVer, extensive the basis bf exposure rate measurements,a tests of nuclear weapons under known decay rates, and probable exposure times, conditions have indicated the kink and but these estimates should be used for extent of residual radiation that could.re- planning purposes only. Determination of sult from the use of such weapons. The actual exposure times and exposures dur- knowledge gained from these and other ing emergency operations must be based types of experiments makes it possible to on both the exposure rate, as read on relate radiation conditions to biological ef- survey meters, and on the total exposur fects bn iman and thus establish equip- as indicated by dosimeters. . ment requirements. 5.4Alpha, beta, and gamma radiations 5.2 Because of the many variablesas-. maybe .present in radioactive fallout. sociated with the detonation of a nuclear Sinte the hazards from these radiations weapon,.it is not possible to predictaccu- will be discussed in detail in later chap- rately_the radiation levels that will result ters, it suffices here to indicate that from fallout. Furthermore, no single in- gamma radiation is an external( hazard strument meets all of the operationalre- and, under certain conditions, bed' radia- quirements that Tight result from anu- tion may also be an external hazard. In ckar attack: Therefore, Li wilie arpability-Addition; thede three types 'of radiation for radiation measurement is required. may be internal hazards. 69 5.5 Alpha radiation does not present an very small amounts of radiation above external hazard, since it will not penetrate normal background radiation. This type of boyond the surface layers of the skirl. Al- instrument would therefore have little use pha emitters m-ust get inside the body in areas of heavy contamination. iii4fOre they can iau-se appreciable damage.- 5.8 To provide adequate monitoring, Bbeause alpha emitters will probably not portable radiolOgical instruments should present a significant hazard relative to be capable of measuring gamma exposure the beta find gamma hazard immediately rates as high as 500 RIhr and also indicate Wowing a nuclear attack and for some when exposure rates exceed this figure. time thereafter, and further, because of Measurement above this amount is not the difficulty in developing portable alpha necessary for portable survey instru- Oeasuring instruments, DCPA does not thents, because a higher level of radiation -provide a standatd instru-ment sensitiveloVionld be so dangerous as to preclude-fur- `this type of nuclear radiation. During the ther surface operations. / recovery phase, the determination ofthe 5.9 When surface level exposure rates seriousness of the*alplia contamination in are very high or when rapid monitoring of food and water will probably be accom- large areas is required, aerial monitoring - plished by laboratory-type instruments. may be practical. Survey meters designed for this purpose must be extremely sensi- MEASURING BETAAND GAMMA tive in order to giye correct readings of radiation levels on the ground. Remote RADIATION reading instruments used to indicate ra- -5;6-Since the biolOkicareffects- of beta -diation leveis outside 'fallout shelters are and gamma radiation differ, radiological_also required _and should indicate gamma instruments must discriminate between exposure rates up to at least 500 Rihr. them. Measurement of beta radiation is 5.10 Within the entire grOup of radiol- complicated by the very wide range of ogical instruments developed by DCPA, energies of these particles. Most beta de- the capability exists for measurement of tection instruments will not respond to ionizing radiation exposure rates ranging extremely low energy beta particles. How- from a minimum of natural background ever, that portion of the beta radiation radiation to a maximum of 500 RIhr. This that can be detected should be detected, so wide range of measurement capability is that its proportion to the total radiation considered adequate for all operational exposu-re_can bie-determined. This is neces- needs. o estimfite possible damage by each- ype of radiation. It should be noted, how- TYPES OF DCPA RADIOLOGICAL ever, that the units of measurement used INSTRUMENTS on radiological instruments to show accu- mulative exposures and expostire rates of 5.11 Each of the DCPA radiological in- gamma radiation are the roentgen and the struments will be dvscusied in terms of its roentgen per hour and the roentgen is uses, significant operating characteristics, defined in terms, of X or gamma radiation important specifications, and the care add expOsure in air. Therefore, these units do maintenance to be ticcomplished by the not relate directly to measurements of instrument operator or monitor. beta radiation. Consequently, meter indi- cations of beta radiation can be inter- 1CD V-700 preted only in a general way. 5.12 The CD V-700 radiation survey 5.7 The sensitivity requirement of a ra- meter (Figure 5.12) is Tt)highly sensitive diation instrument depends upon the type low-range instrument that can measure of information itis expected to provide. An gamma radiation and discriminate be- instrument used to measure the Contami. tween beta and gamma radiations. DCPA nation of personnel, food, water, equip- recommends its use primarily in long-term ment, or living quarters must Andicate 'clean-up and decontamination operations!' 70 s ? , 9. EI:ECTROMAGNETIC.INTERFERENCE: the instrument shalloperate properly in normally encOunteredelectromag- netic. hey's. 0:tOPEEATiCNAL CHEZt SOURCi: -aper- menentlY sealed radioactivesource shall' providea reading of 2 mR/hr 0.5 .mR/hr when the probe, with beta shield Open, is lieldover it. 11. BATItERY PPE: 100hours continuous use (Minimum).

.OPERATOR. USEi. CARE Ik.t4D MAINTENANCE:OF THE-CDV-400 5:14 Batteries.,=-Whetiever theinstrument fails tO respond to theradioactive FiGuitr5.12.CD'11-700, lowrange beta-gamma source on the side.of the instrUment, check survey meter. the batteries. Replace bad batteriesin ac-

cordance with the instructions inthe man-. 5.13 The inst mentcan also be used in ual accompanying the instrUment. 1 training progranis wherelow radiation ex- During extended storage 13eriods1the *pure rates will be encountered.The de- batteries should' 46 remóved froth' the tecting. elenient of the instrument and' stored iiia cool, dry -CD-y-700 isa plece. _ aiig0 Aub6 :Shielded ' -- so that only the Battery cOntacts should beinspected gainme-eXposure rateismeasUreddi beta monthly, and. any .dirt and- garnina cen be detected together or corrosion-present with should be removed..Whenever theinstru- the-Shield- open. A headphonefor audible mentis not in ruse, MAKE CERTAIN IT fS, indicatiOn is sUpplied withthis instru- : Ment. TIMNED oFE:; otherwise, -the.batteries willbe 'depleted and' theinstrumetit Ten., .dereclineffectiv,0, a

IMPORTANT SPECIFICATIONSOF THE CD 5.15 Geiger Tu0s,TheOeigertubes, in. the4later-tOdeli-of the =0 Vi--7011-atelialo-_ 7 gen:quenched -so Iliet tbeir,opereting 1. -RANGE: 0-0:5; '0=5;0, life 0-50 milliroerit-is linaffeeted.14r,lise,anci,,therefore,rarely,, gensTerliour. xequirefz_replacenient ifOivever,Wlien-fre0h:' 2. DETECTS: beta endgamma-radiation. betteriesere installed:and:the instrUment 8-. A660146: ± 15% oftrite exposure does not woric 'correctly, jt-rno fieceg,-_, -ratotwtobaitio -0 cesium137. -satY to replace the Geiger tubeTo,check 4, 'RESPONSE 9'5% -of filial reading fOr a faulty Geiteg tube,replace the sus! 'in-aiProXimatelyseconithr. % towed- tube' with .a goecVtube 4'roina properly lopeiatinrOD V2700., TEDOERAii.OftElirkstrumentShall oper- atO properlyfrom7 10° F, to + 125° P. 5.16: Hedclphones..If theoperator ; inistruMitntshallwerate.6hoOies t. uie theheadtliones with- the proPerlY from,sea level to 25;000 feet. in'struinerit, they MaybescreWed into the. connector provided at the lewer leftCorner 1., JAMMING: .e*pOsurerates from 50 mil-of the initruinent 'cover: I* , liroenigeris4er,hour using the to 1 roentgen. per heiaphone, the operator will lionr lif*O'procluce.,off-scale readings. note that each litilse-er co4nt is indicated-by a dis- ,svslolTryitn. sunlight tinctly audible. ciick. ilav_hen the -Sh headphones iancif siffeCt the O' orationof the ere .not in- use, the protectivecap on the headphone receptacleshould be 'replecodi.

71- *-171

5.17 carrying Strap.The instrument -may be carried in the hand or by a strap over the shoulder: The strap anchors are iirranged in such a way that the meter is -sisible_when egrried over_the...rightehOult der, 5.18 -Controle.There is only one control on this instrument for the operator's _use. This 'Control, called the selector switch, includes *an off position and three 044 labeled X 100, X 10, and X-1. On' the' X .1i-the X-100-rangesrthe meter readings must be multiplied by a 7:factor 10,. and 100,_respectivelyto obtain themeasured exposure rate. 5,19 Operational Check.The selector FIGURE , 5.2,1=cD -V,715, high-range- garkinsi supey Switch shouldhe turned to the X 10.range, niitter. Tile beta shield on the probe-,should-,ber.. - rotated. to the fully open position and the _probe placed_ as close as possible to the ogical-monitor for the major _portion of_ radioactive sample located, either on the survey, requirements in the periodimmedi- bottom. surface of the .case or .underneath ately following a nuclear weapon attack. -the manufacturer's name plate (see in- The CD V-715 hag replaced the now obso- struMent manual). The open. area of the lete CD V410 mediuitrange 0-50 R/hr -Trobe _must bedirectly facing the radioac-. eamma snrvey meter. meter should be adjusted \toireatt:-2-1 5 millitoeritgens-per hoOr. No external radiation must be present when MPORTANT SPECINCATIONfOisTFTE -0 iP10.010.his,:tcheclo. The source shouldbe 1/4715 _ nsed,:te."determine the operability of the -instrument.only. It is not intended to re- 1. RANGE: 9-0.5, 0-5.0, 0-50, 0-500.roent- .:place:the need for calibratinft the instru- operate from -20°F. to 110° F._ ment affainot a.known source. 2., bETECTS: gamma radiation. only. ._540 .Calibration,Theinstrument 3. ACCURACY: -± 20% of true exposure rate should be -calibrated periodically to yerify from cobalt 60 or cesium 137. that it ismeasuring correctly. 4. SPECTRAL DEPENDENCY: ± 15% for, _

_ v.21 Contamination.At .41 times the gamma radiation energies between 89 =operatorShOuld etteMpt to preyent radiol- keV and 1.2 MeV. Ogical-contamination of the inStrument, 5.gp$PC04_r.1.4_,P; .95% of fiO4 reading partionlarly of the, probe. in. case of' con- in 9 seconds. .taniinlitieri; the instriimerit can be cleaned 6.TEMPERATURE: instrument shall oper- Cieth dampened in, a -Mild soap solu- ate properly from --- 20° F to + 125° F. '_tion.--- 7.PRESSURE.:-..instrutnent-shall operate properly from sea level to 25,000 feet. 1/4,14 8.JAMMING: exposure rates from 500 -6.4 The cp V-415 (Figure 5.22) is a roentgens per hour to 5,000 roentgens -.high-range gamma survey meter for gen- per hour shall produce off-scale read- --,e-farpOitattack operational use. The ings at the high end. , tecting -eletrient .of, the bp V,-715 is an 9.ELECTROMAGNETIC INTERFERENCE: in- ionitationehamber.. The instrument is de- strument shall operate properly iri nor- _....signed, tor, ground. survey and for use in mally encountered electromagnetic fallOnt shelters. It Willhe used,by a radiol- field

1 77 .01111tATORAISC,:CARE AND 715 should-be zeroed fiequently, at least JAAMINANtE 00-THtieD-V-11'5, every half hour. 5.27 Calibration.-7The CDV;715 p4tter4-Bgatery.replacernent is should be calibrated periodically to vOfy ,noxinally.:regnired, whenever_ the instru=-- ,ment,Canrno.longer be zeroed or when the-the acctiriCy of ifs measurements. .rnaer, indicates below the "CIRCUIT -5.28 Contamination.The operator flAND".. Batteries should, be re- should attempt to prevent radiological placed in accordance with:the instruction contamination of the instrument at all, in_ the instrument manual. If the instru- times. In case of contamination, the hi- ment i. to be stored for more than a few stfument can be'cleaned by a cloth damp- ulfelc,s-,,the batteries should be removed a-nd ened in a mild soap solution: stored in- a coot dry,location. For instru- 5.29 Modification (c:D A77717:).-7-gqin, inentSin;cofitinuoUs use, batteries should of the CD' it-715's are etjuipped by the be refoOred monthly and the battery con- manufacturer With a removable ionization tacts cleaned of any dirt or corrosion pres- chamber attached to 25 feet of cable. This ent.. modification, called the CD V-717, provides a remote reading capability' for fel.- 5:24 Controls.Two controls', are pro- lout monitoring station's. The ,operating vided. One control, the selector switeh, has characteristics are identical to the CD V- seven positions: ciicuit check, off, zero, X 715 except that the removable ionization 100, X 10, X-1, an X 0.1 ranges. On the X chamber-must be placed outside the 'shel- 641.;_)r 1, X 10, and100 ranges, the meter ter in an unshielded area and protected readings !mist be _ultiplietby_ a aC,torsc_frompossible contamination,by placing itf ();I: `1 16; -Eta rtibi reepectiirely in order to in a bag or corer of light-weight material.' taiii,..thp, measured exposure rate: The All readings Mak then be, observed from "seco:nd cOntrol, the zerO Contrel, is used to within the fallout monitoring station. ad,j4ithe Meter readhig tozero during an After the early .periods of heavy fallout operatiOnal check. and -the requireMent for a reripte reading -0:25 CarrYing SWap.The instrument instrunient din:finishes, the reinovable ion- Pci!lipped, with a carrying strap whieh ization chamber should be checked for con.f allay be adjusted to any length-to suit the tamination With the CDT-700; decontami- operator. nated if néceSSary, and ,returned to the case. The eD V-717 inay,then be vsed for __0.fierational" Cheek.rtirp the se- other rOonitoring operations. :lector :Oilteh:io the- Op position, wait-a tube to Warin UP and adjust the zero control to make the-rneter read zero. Turn the selector SWithh to ,the circuit check position. the Meier should read, within the red 'band,inarked "Circuit..Check": As these- "lee* switch is turned through thezera pbsitibit to the four ranges, recheck the, 'No the- selector switch to the.X_JOk X '10; XI, and X0.1 range.,, 'When_iia'radiation,ls present, the reading shO41i1 not be More than two scaledivj- ions uP 'scale. If difficUlty is .encountered step in the Operational cheek, 'referio the-instrument Inanual forcorreci._ Ore, tiroOdure._ _Many medels have inter- = ba,:tidjuetinents: which May,Cprrect the _ ' difftu1tyDuing4rma1 ugeLthe COY, ____FIGORE..5.29mtOPS,71.7.,Itemo eion,Chamber- -74

44% ' - _ - _

- -.0-IC7 ':

noulet-6.366742k1.,teta-gamrna-survey meter.

CO V-720_ FIGURE 5.32.--CD operational dosimeters. = . 5.30 The CD 'V-720 (Figure 5.30) is a high range (0-500 Whr), beta-gamma, sur- 5.33 DCPA has procured three dosime- .-. vey meter designed for postattack use by ters for operational use. These are the CD Monitors. It will-be used in high-levei con- V-730, with a range of 0-26.roentgens, the

, tamination-areas where civil-preparedness CD V-740, with a range of a-loo rbentgens,, operations -are necessary and for -making and the CD V-742, with a range of 0-200 hi6,71eVel beta radiation determinations. roentgens. The CD ST-730 is used when a, e Federal agencies maintain a monitor expects:small repeated exposures ,PlOilije number of these instrtVents to over a long period of time. The CD V-740 fulfill' *it SPecial requirements. The de- and cp V-742 dosimeters are recom- tecting ,element of the CD V-720 is an mended for use when personnel could be .iohization_ chamber,_ shielded so that accidentally exposed to large doses of ra- gamma radiation only can be measured, or diation. They should be used when person- both beta and gamma can be detected. with nel are required to enter fields .of high the shield open; radiation or remain* low radiation fields for long -periods during. postattack sur- OPERAPPRUSErCARE AND vival and recovery missions. After current stocks of the CD V-730 and OD V-740 are .,:mmtirgsmcf OPTHE CD V-720 depleted, DCPA will procure and issue the, 5.31 The use, care, and maintenance of CD .V.442 only. For training purposes, the the C,D y-qp, are similar to the use, care, CD V-138 with A range of 0-200 milliroent-

= :and maintenance of the OD V-7I5. (Refer gens is,recommended. to-paiagriaphs,5.4to 5.28 fOrdetails:) .

CD DOSIMETERS 7 IMPORTANT SPECIFICATIONS OF THE db DOSIMETERS

, , 5:32, Personnel. who ,muSt work in con- _larninatecl .areas require radiation inte- 1. RANGE: CD y-138 0-200 milliroent- gratinginstrurnentS to keep them continu- gens ,,; t ously inforined df their exposure. For this CD V-730 0-20 roentgens purpose DOA recommends the Use of the CD V-740 0-100 roentgens 1401f-inckatjng -qOartz7fiber electrostatic CD V-742 0-200 roentgens 2. DETECT: gamma radiation. - , , , . 79 , Acbxtit4e 10% 'of trueexposures fromccobalt0-orcesiuin 137 4. SPECTRAL DEINDENCY::t 20% of true exposure for gamma radiation energieS -between 60- keV and 2 MeV. 15. ELECTRICAL LEAKAdE:CD V-730 and CD It-742. Beginningten minutes after exposure,, leakage shall not exceed5% of, full seale in a fonr-hourperiod. Begin- ning 48 hours afterexposure, leakage shall not exceed 2% of fullscale in 96 hourS.- CD V,440. Leakageshall not-exceed 2% of full scale in 24 hours. CD AT-138. Beginning 10 minutes after - e exposure, leakage shall not exceed5% FIGURE 5.37,-CD V-750, dosimeter charger. of full scale in 4 hours.Beginning 48 houri afterexposure, leakage shall not exceed 3% of full scale in48 hours. before use. A secondcharging may bere- 6. GEOTROPISM: readingshall not vary quired before theinstruments are ready more _than -±4% of full scale whenro- for operation._ tatekabout the horizontal axis. 7., TEMPERATURE: instrumentshall oper- CD V-750 itte-prePerlyfroin -40° F to+150°F. 5.37 The CD V-1750 doiimethrcha ger is _Instrument -shall operate used to read and charge .properly fromsea level to 25,000 feet. self-indicating eleCtrestatic dosimeters(Figure 5.37). A 9: SHOCK: instrument shaljAilierateprop- standard 1.5 volt flashlight erly after four drops from cell is used as a height of the source of electricalpower. lourfeet.Ontoa hard:wood floor.

IMPORTANT:SPECIFICATIONSFOR THE 'OPERATOR.USErCAREAND -co V-750 moTOIANcE.oF:THE,Dosuoultot 1. JAW& VURCE: '.5:34, -Afaintenance.NO instrument mustpro- maintenance vide itrumination forreading and/or should 'bp performed bYthe 'titer on the charging the dosimfiter. -self-indicating electrostaticdosinieters. 2.TEMPERATURE:instrument shall -oper- 6.35' th,e instrunientaare 'received; tbe operator ate properly from -20° Fto +125° P. should check the 3.PRESSURE:_ _ instrument shall operate abilityA&-zero the-dosimeter,cheek ita properly ?rom sea level response to-raliationcand.,dheckits electr- to 25,000 feet, .iCal reakage characteristics. 4. SHOCK:instrument shall oPerateprop- When Using erly after 6 four-foot the doshneters, theoperator should' keep. drops onto a hard ,as cross, to -,iero- as possible wood floor. .and Shoul4 preVent -thedosimeter front becoming --centaininated. Whennot' in use, OPERATOR USE, CAREAND thedOsimeters should ,be chargedand, sto- MAINTENANCEOF THE CD V-750 ,,,red'in . 5.38 Batteries.The 1.5volt flashlight Since most ,eleetrostatic dosime- cell should be replacedwhen the lamp ters.mill require -a "soak-in"charge' after dims noticeably toneternt sterageln 'an on actuating the charging. uncharged condi- Switch. Replace bad _batteriesin accord- Such. dosimeters should be charged ance with instructions in the andthe reading obserVedfor a few hours instrument manual. WHENEVER THE_INSTR15:7_

7'5 NT IS: STORED FOR moRg THAN A W WEEICS,, TtlE. BATTERY SHOTILD MQVEDTO PREVENT FOSSIBLE

_ . .39dpiii-44n8.-----To read a dosinieter; oye the dust cap- from the charging tack,,plage,_ the- dosimpter On thetcharg- contact, arid_ press lightly to light the k. Read:the dosimeter and replace the ,d st Cover -when finished. -The dosimeter alsobe read by holding it toward any ight ieurce suffi.Cient to illuminate the airline. To-.chargea 'dosimeterfollowthe precedure printed on the CD V-750. FIGURE 5.41.geiled source -capsuies, Open and ca sealed. N-457 (Figure 5.40) is a Geiger counter which has been especially sealed sources (Figure 5.41) and accessory designed for elissroom demonstration use. equipment. It should be hoted _that this Tt operates on, a normal 110.volt AC power Training Source Set has been designed supply and produces both visible .and audi- specifically for use in training exercises

, ble responses cO_ritiCle'ar -radiatiOn:-The-and is riot intended as ari acculatecalibFa- instrinnent ia used "in 'teaching basic -nu- tion source. -clear radiation plmics and for decontami- DAVI:he CD V7-778 Training:Source Set 'dernenstr ation . fr440n-, e, consists of the tollowing itemth 6-5.0 mCi ,Cobalt 60 Sealed Spurces ,totaling §0 mCi, CD V-784 1-:-Lead Container, small CD V-791) 1Lead Container, medium (CD V- 792) 2LoCis foi Lead dontainer CD V-792 1Long-Handled Tongs for Handling Sources (CD 11-788) 87-Radiation Area Signs 2-07200 mR Dosimeters (CD V-138) 1-,,-Dosimeter Charger (CD V-750) 1Geiger Counter'-(CD-V-70_0)

CO:V-794; 5..43 'The CD V-794 (Figure 5.43) is a calibration unit containing a Cesium 137 Source of approximately 430 curies. The primary shield...is composed of" depleted FIGURE:5.40.PD-V-457, classroom demonstration uranium, and is sicaped te beam the radia: unit. thin from the radioactive cesium into a Shielded ekposure'chaMber. Interposed in the radiation beam path is an attenuator tp;i1418 disk by means of Which radiation levels of 5.4r ',The CD V-77840- millicurie Train- 0.4, 4,-40, And 400 R/hr are produced in the ing Slurce Set consists ot six Cobalt 60 exposure chamber. Jigs are provided to

- .1.r_°.1.1 '8:1. FIGURE 1..42.--CD, V-778, Wainini(Source,Set.

properly position the instruments during beamed vertically. The aperture is nor- calibration. The range switch and calibrat- many dosed by a_ tungsten plug whiPh is ing petentiotheters are adjuStell through flexible linkages leading outside of the exposure chamber. The Unit is designed to prOvids,tiitable protection from radiation hazards fothe oPerator. "CD1/457 5.44 The barrier Shielding Demonstra- ter .$4, bb IF-1-51, is a low range radiation ,deteetion instrument, couPled-tcra neon ,lighted remote readMit indicator that'is readily visible' in large conference rooms br sin1l Aud1toitOr1s1-44t4,:the large, 414 catfir, a Jec,torer, can show:how radiation frOM a radioactiire souree is, affected by distance4ndahielding. **OR amv.mt ,Of cesiunt 137, which glyet off gamMa rays, is housed ina leadoom hall:hiounted in the dernpstratjon plat- term. A hOte in the pdatf6rm leads to the .efs,tuni SoiirCe, and gamma radiation is FIGURE 5.43.CD V-794, calibration-unit. 82 77"

4 104:740

aiflocied in ,poition. Abupted directly .ppstattacicperatiouase in slow low- .oyiirthelole Cs 4 ,-cwor ghlier tube that flying aircraft. The 78r will. be -u'sed is 4*, t e radiation beam when ,the by jsPecially trained, monitors. The four major. comPonen'ts of the Ci), Y-781 aerial a.-radiation absorbing mate- suryey iet aret detector'unit (three Jj40jst..04hp.:,,plattfkrm hole, the intensity of deigey-Mueller tubes); -Metering _unit with e.rs,01,09,/y-beam is attentytted, result-,"three range R/hr, 0-1,0 Rihr, .4.,:10440Wep.eiposure,rate readout. Cora,- and 0-10 R/hr); sinnilator unik:With dials corresponding iO the metering uhit; and a palsoni3Of ,rA4,44404- 4bsorbing materials , r aty =Yea.* ,-placingtem- in magnetic tape recorder. hradiation i*eAtifery-ifiriple Mathematical rola- IMPORTANT seggIFI TIONrco THE CD, diStances from 0.,. , 4ouree'4,-,f4Monitrated 11F.,00.3bling V4111 3#PlirP,4 deteetiir and_ 1, AANGE: 0-0.1, 0-14), and 0-10 roenV y Otiing:1 Met dpon the gens per.hour. elbn t e large indicatoy 2. ,N.TCTS:,gannna, radiation only. 3. ACCuitAciet:4--1-06/0 azDtrueeipoture rate from Cob.41Pqao-orCes,luill-P7-- Aerial 'aryeY Me- ..c.ALORA.,:Twm. is, perform'ed by the esigned for limited $i4t.e maintenan'ce shops \7- ' .5: TEkPERATURE: the instrument willthe 'metering unit into, the aircraft, - ,operatfrfroni- 20°--F. to the i10°F. instrument,s_houldbe. operatiOnally ipmarimm-to 95%: 7- checked' with-the use of the simutator 1. AiTiTUDE,;- to2G,000 feet; preferably unit.- . below 1,000 feet. - The folloWing procedures should be use&T OPERMING-TTME: 40 'hourson nine 1. Attach-the cable of-the metering.unit 'flashlight batteri.e.s ("P" to- the connector provididon the sim- cent ulator unit. . 4, TRACKINGERR,OR; between t e ':ta ?itials-nsit themetering dials shall 2. Position the ,power switchon the me- not be'nfO're -than10%. terinb grit to "Battery" powerposiz 10. READiNG TIME: not lessthan 15 section. and,gerv the instrumenta war- ondspreferably 1 minute. Mup period of at least 2 minutes. 11. SliOCK AND. VIBRATION:instrument is, 3. By rotation of the meter-readingcon- designed to withstandnormal shock trol knob on the simulator unit, check and vibration encounteredin small each of the three meters at half scale. aircraft operations 4. Starting with themetering control : -"; 12. ,DETECTOR UNIT:containsthree knob in the extreme counterclockwise Geiger-Mueller tubes similarto the CD position, slowly rotasie the knob clock- - t-700. The detectorunjt should be wi4e. The tracking error between the.: carefully handled wheninstalling bat- meirs of thesimulator unit and cor- teries,. . responding. meters, .on, the;.metering TIARMUii liME: 2minutes., unit should be no, more than 10% at . " any simulated-expOsure.. ,fate. opERAtiON'At- ado iitioaDoitEs- '5.47-Tlie--audiOTOiitPhtmay be. checked 5:46- Ifetering ekrit.--Trior-to- by plugging in the headSet to the metekug mounting unit. TheTalir:iiio oUtp,hRittld be onr..225. , . - - r, -.; J , 1 - -

vie

$AtiA.":00*:11tiii4i=iiletet-', ". - .,CD 'VI-781, odel =1 . _I _ .?",r

, 79 4

to 275 cycles per second (within one or Wo . at, or slightly above, the battery -notea of iniddle c) for normal radiatiOn check poInt. 4 background. The.3udio output can be oper- Aircraftl7ower Supply . ated with the simuiator unit. \ a. When the aircraft electrical itioter 8.48 Afte(r installation of the CD V--7g1 ,skurce is used, position the power _Aerial Survey Meter into the aircraft, the switck on the metering unit to the operational check is performed as follows: 'Plane" power fiosition. In\silintent Battery Supply" b. Repeat steps c and d, above. a. Observe meters prior to turning on b.'intrumeht, Meters should indicate zero within one scale division THE TAPE RECORDER (the instrument has no zeroed- 5.49 The manufacturer's manualsup- justment).. plied with the recorder indicatesprecau- b. Vosition the power switchon the tions to be lbserved arixi provides detailed m'etering unit to the "Battery" instructioni for operation. A monitorex- power sWitch position and allow pecting to Use the redorder should,practice the instrument awarmup period .of using it until he is proficient botlion the at least 2 minutes. ground and in flight. The recording and c. Observe the meters after warmup playback of preliminary survey informa- period. Meters should continue tortion will provi4e a cheek'of the recorder's indicatezero within one scale divi- operability. Prior to a mission, the '"Bat- sion when onlY normal backgrouliti tery Voltage Indication" .should be obi. radiation is present. In the event served and batteries repiacedNif required.. external radiation from fallouctr; prohibits.this hheck, it "sfii4ro-be ' 1 4sStinted the instruinent is operat- REFERENCES ,ing properly if it indicates radia- Handbook for Radiological Monitors. tiiin levels alfove normal back- FG-E15.9, April 1963. Instrument manuals ground. accompanying eaCh instriment. *d. "Presi the -"BattfkrY Check" switch. Handbook.for Aerial Radiological Moni- The 9-0.i 14hr met-er 'should read.tors.FG--B-5:9.1, July 1966.

v CHAPTER 6

RADIOACTIVEFALLOUT

NOw we are ready fora closer look at our to learn more about fallout thatwe start enemyRADIOACTIVE FALLOUT. We- to lose sight of this central and simple have learned how it is produced througha idea. Words like "clean bomb" and"dirty nu'clear detonation andwe have learned bomb"; "early fallout" and "worldwide-fel: how to measure it when it arrives.This lout"; "fission products" and "fusion prod- prompts a question: ucts"; "local fallout" and "late fallout"; Must we wait until fallout actuallyar- "surface burst" and "air burst"; "stron- rives before we canecide where it is tium 90" and "carbon 14'z makenS-w-Onder going and what to do about'it? if we know what fallout is after all, despite .. and the answer is... that built in definition. So, letus look at .NO! ! ! these words and see what they-mean.

True enough, we cannot detect norcan SOURCES OF RADIOACTIVE MATERIAL -we-measure fallout before it arrive§ biit we definitely do not have to just sit and wait 62 Lei us first-es:insider wriere thera- for it. Although it mayappear that the dioactive material in falloutcomes from? :fallout makes itsown rules, .its movement How many Sogrces are there andare all . r , is affected by. a number of elements,some' equally important? s,. of Which we can meast.ii-e. This letsus 6.3 When uranium or plutonium are-fis, make predictions about the behavior ofsioned the heavy atomsare split into fallout, to estimate its location. In shortsmaller atoms and k.yast arnouit ofen- :tyhen we take qur close look at fallout in eigy ia released. Millionsupon millions of thia chapter, we5villsee how RADEF tech- these atomic nuclei are split...or fissionedin. niqiies can prov,ide life-savingand morale- the explosion of a nuclearweapon. About supporting warnings of the directionof 200 different isotopes of about 35 elements fallout Movement. We willsee: are produced as fission products. Most of WHY there is fallout these are radioactive, decaying by-emis- a sion of beta particles frequently- HOW.* accom- fallout is,formed .. Panied bygamma radiation. TheSe -fission -HOW.it, rs sPread -' t,products constitute t\he largest single .WHAT influences that spread source ,of radioactive material in the tel- .- lout. WgERE :is fallout most likely to land 6.4 What about the radioactivity of WHEN, to expect it the fusion products? The different fusionreac- tion* used in fissionfusion,type.weapons may:prOdncetritiiiiii '(a radioactiire hydro- INTRODucTION .ken isotope) ,and the neutrons produ'cedin the reaction' thay cause the formation -of,- 6.1"FallaUt" is one- of those words radioactivekarbon (carbon 14)from the which define thernselves. Say the word,.nitrogen in the air. However, the carbon and you haVe graspeds eaSential mean- 14 produced is small relative to thatnor- ine the fallback-to earth of radioactive mally present in the atmosphere. Only in- /34irticlesiirodnced by the detonation ofa sofar as possible genetic effectsmight the- *iciear weapon. It is only *whenwe begin oretically, f3e incurred over the nextsev-

0 -;1 4 eral thousand years could carbon 14 or Any radioactive isotopes produced by neu- tritium be considered passible hazards. tron captore in the residues will remain Otherwise, fusion products are neglected associated with the fission products. In :as an illtportant source of radioactive ma- the period from 20'hours to 2 weeks after terial contributing to the immediate post- the burst, depending tO some extent upon attacksurvival problem. the weapon materialsj such isotopes, as 6.5' The uranium and plutonium which uranium-237 and -239 and neptunium-239 may have escaped fission in the nuclear and -240 can contribute up to 49 percent of weapon represent a further possible the total activity of the weapon residues. source of residual nuclear radiation. The At other times, their activity is negligible fissionable isotopes of these elements emit in comparison with that of the fission alpha particles and also some gamma rays products. of low energy. However, because of their 6.9 An important contribution tol the very long half-lives, the activity is very residual nuclear radiation can also Arise sziall cornpared with that of the fission from the activity induced by neutron cap- products. ture.in certain elements in the earth and 66 It will be seen later that the alpha in sea water. The extent of this radioactiv- particles from uranium And plutorfium, or ity is highly variable. The element which from radioactive sources in general, are probably deseives most attention, as far -7 completely absorbed in an inch or two of aS environmental neutron-induced activ- air. This, together with the fact that the ity is concerned, is sodium. Although this- particles, cannot penetrate ordinary cloth- is present only to a small extent in aver- ing, indicates that uranium andplutonium oage soils, the ,amount of 'radioactive so- deposited on the earth do not represent a dium-24 fornied bY-neutron capture can be Serious, external hazard. Ev,en if they ac- quite appreciable. This isotope has a half- tually come in contact with the body, the life of 15 hours and eniits both beta parti- alpha particles emitted are unable to pen- cles, and more important, gamma rays of 'etrate the unbroken skin. relatively high enertsy. 8-,7The last source of-radioactive mate- 6:10 How much radioactive material is rial, to be considered is the neutron in-, available for distribution as fallout? duced activity:The neutrons liberated in 6.11 At i minUte after a nuclear explo- the -fission process,'but which are not in- sioh, when the residual nuaear radiation volved in the propagation of the fission has been postulated as beginning, the chainare ultimately captured -by the gamma-ray activity of the 2 ounces of fis- weapon materials through which they sion products Ow a 1-kiloton fission yield must, pass before they can escape, by ni- explosion is cthnparable with that of about trogen (especially) and oxygen in the at- 30;000 tons of radium in equilibrium with mosphere, and by.. various.,elements pres- its decay prodiicts. It is seen, therefore ent in the earth's surface. As a result of that for explosions in the megaton-energy capturing neutrons4ubstances may be- range the amount of radióactkvity pro- come radioactive. They, ,consequently, duced'is enormous. Even though there is a emit beta particles, frequently -accom- decrease from the 1-minute value by a panied by gamma radiation, over an ex- factor of over 3,000 by the end of the day, tended period of time following the explo- the radiation intensitly will still be large. sion. Such neutron-induced activity, there- 6.12It has beenalciiilated that if all foreris part of the residual nuclear radia- the fission products' from an explosion tibn. with a 1-megatim fission, yield could be 6.8 The activity induced in the weapon spread uniformly over a smooth area of materials is .highly variable, since it is 10,000 square miles,, the radiation expo- greatly depenaeint upon the design or sure rate After 24 'houts would be 6 roent- structural characteristics of the weapon. gens per hour at a level of.,3 feet above the ' Paragraphs 6.5 through 6.18 are reprints of elected paragraphs ground. In actual practice, a uniform dis- from The Wets of Nuclear Weapons. , tribution would be improbable, since a el 8 '7 large proportion of the fission products surface, casualties due to falloutwere , would_ be depositednearer ground zero completely absent. than at farther , distances. Hence, thera- 6.15 On the other hand, a nuclearex- diation intensity will greatlyexceed the plosion occurring ator near the eartit's average at points gear the explosioncen- ter, whereas at Illaell greater surfaee can result in 'severe contanination distances itby the radioactive fallout. Inthe &sè o 'will usual y be less, The'above example the 15-megaton thermonuclear devic does not i elude any neutroninduced ac- tested at Bikini Atoll tivity. on March 1, 195 the B,RAVO shot of Operation CASTL FORMATION OF FALLOUT the eniuing faliout caused substantial contamination over an area ofmore thari, 6.13In a surface burst, largequan- 7,000 square miles. The contaminatedre- titieS of earth or water enter thefireball gionwas roughly cigar-shaped andex- at an early stage and are fusedor vapor- tended more than 20 statute milesupwind. iz.ed. When sufficient cooling hasoccurred, and over 320 miles downwind. The width . the fission products and otherradioactive in the crosswind directionwas variable, residues become incorporated withthe the maximum beingover 60 miles. earth particles as a result of the condensa- 6.16It should be understood that the tion of vaporiz-ed -fission productsinto fallout is a gradual phenomenonextend- fused particles of earth, etc. A smallpro- ing over, a period of time. In theBRAVO -portion of the Solid Partieles formed upon'-' exPlosion, for e ample,about 10 hours 1 further cooling are contaminated fairly elapsed before t e contaminatedparticles I uniformly throughout with radioactivefis- began to fall at t e extremities ofthe 7,000 sion produCts and other weapon residues, square mile area. By that time, the radio- i but in the majority the contamination is active cloud had thinned mtto such. an ,.. fonfid mainly jn as thin shellnear the sur-extent that it was no long,* visible,This face. In Water droplets, the smallfission brillgs up the important factthat fallout product particles occur at discretepoints can occur even when the cloud cannot be 'within the drops. As the violentdisturb-_seen. Nevertheless, the area of contamina- ance due to the explosion subsides, the tion which presents the most serioushaz- 'contaminated particles and droplets grad- ard generally, results from thefallout of uallr fall back, tO-earth: Thiseffect is re- visible-particles. ferred tol as the,"fallout". It is theassoci- 6.17 The fallout pattern1 fromiparticles ated radiioactiviiy in the fallout, which of visible size will 1-ive beenesablished decays-over a long _period of time, that is within about 24 hours after theburst. This --- the main:SOUrde.of residual nuclearradia- is referred to as "early-fallout -tións. and-is also . sometimes called "local" br "efose-iefal- 634 'Thelektent and nature of thefallout. In addition, there is,thedeposition of -can r nge between Wide extremes. very small particles Which,descend very 044he-actual behavior willbe determinedby slowly over largeareas of the. earth's sur- a Combination -of cireumdtances aisoCiated face. This is the "delayed fallout,"also With the ,energy yieldand design of the referred 'to as "worldwide fallout,'-'to weapon, the height of the explosion,the which residues, from nuclearexplosions of nature of the surface beneath the pointof various typesair, bigh-altitude, burs surface, , and the meteorologi al conditions, and Shallow subsurfacemaycontribute.. which we willfdiscuss later. In the case of 6.18 Although the test of March1, 1954 - dr d r bare, for example, occurring at an produced the most extensivelocal fallout appOciable- distance above' the earth's yet recorded, it should be -pointedout that; "434iftiCe.,'So that no surface materialsare the phenomenqn was not necessarily sucked into the -cloud, negligible fallout char- s is acteristic of (nOr restricted to)thermonu-, prOduced Thus at Hiroihima and Naga- clear explosions. Iis very probable that if ," Saki, where approximately P-kilotOnde- the same device h &been detonatedat an 'i Ivicet Were ekplocled 1,i5Q feet abovethe 7 appreciable distan e above ,the .CoralIs- ' ' 83- , , land, so that the large fireball did not 6.23. Height and bintension of the toUch the surface of the ground, the early Cloi.41.It is obvious that the phYsicat.,ske fallout, would have been of insignificant of the cloud at the time of stabilization proportions: will have an effect on the distribution of early-fallout.:The height to which the indi- WHAT GOVERNS THE LOCATION OF vidual particles are carrie.d principally de- EARLY FALLOUT- termines how far downwind a giVen par44- cle size will drift, and the horizontal ex- 6.19 There are several factors goverrk.tent of the cloud affects the width of the ing the location of early fallout. These are: area over which fallout will occur. 1. Kind of Weapon. 6.24 The eventual height reached by 2. Yield of the burst. the nuclear, cloud depends upon the en- 3. Altitude of the burst. ergy of the bomb ahd upon the tempera- 4. Ileight.and dimension of the cloud. ture and density of the surrounding air. The greater the amount of energy liber- 5. Distribution of radioactive particles ated the greater will usually be the up- within ,the cloud. ward thrust due to buoyancy and so the 6: Radioactivity associated with various greater will be the distance the cloud as- particle sizes. cends. It is probable, however, that the 7.. Rate of fall of the particks. ' maximum height obtainable by the nu- 8. Metecirological conditions, illauding clear cloud is affected by the height of the wind structure to the top of the cloud: tropopause, which is the boundary layer arid...ariy type of precipitation. ,between the xelatiiely stabje air of the 6.g0 These faCtora are so interrelated Istratosphere and the more turbulent thatjt is .almost inippssible to isolate the osphere. (See Figure..6.24.) Teifedts O:*ani orie factor:-(Tith pkecision. HoWeVei, -it is possible to discuis the gen- STRAfOSPHERE etal sigkificance of each factor. f-TROPOPAUSE ; 6.21 Kind, of Weapon.Since the fusiOii -TROPOP,HERE products-do not niake a significant contri- butiokof 'Pailioactive ,matefial- o-fallout, ..--...... , -even --whe-n-.trie-Welpon fs adiermonuclear ,-- -,. one (i.e., fiiiion is involved), onlytli.e fi8- siot yield 'of ovioen Weapon is important N Iv- ln.deterraiiing_the total_ amount of radioac- N :::tii)e..fallout: Tor example, although the to- / --_tal--arnount of, radioactive material pro- / -cinOed-'would.be aPproximately the same in / . a'1.nregatdn.50% "fission. yield weapon and /? 'a 2 niegaion.25 .% fission yield weapOn, the o lk:). .- . % =--reSUlting' fallOnt Patterns would -probably \ diffe,bcause of the greater height ob- FIGURE 6,24.-144 eartills atmosphere. talined iisr the 2 megaton. cloud.

--0.2'2Altitude of the Burst (This is a crucial factor).The fraction of the total 6.25 The height of the tropopause is radioactivity of the bomb residues that usually slightly above 50,000 feet in the appear in the early fallout depends upo)tropics and at 30,000 to 40,000 feet in mid- the .extent that the fireball touches tlie dle latitudes in the summer. In winter, in 4urface, Thustthe proportion of the availa- the middle latitudes,. it is somewhat loWer ble' activity ocontributing, to early -fallout on the average than irr4he summer. For increases, as the height of Intrst degreases smaller kiloton. weapons, the height of the and irrore.of-the.firehall conies into Contact tropopause generally limits.the height of *016 -aretil; the nuclear cloud. t ven for larger si*e " . -." - q9 -FAET '130,000'

Il0;000

90,000

70,000

50;000

30,000 . roo,KT . 1)41 '.-za MT . . ,.: FIGPRE 64:Representative nuclear detonation cloud-heights.

I We-46ns in the megatori range, the devel- cron is r millionth of a meter). It isAuite 4irtent of the cloud slows downas the'possible that even smaller particles exist alOud builds upinto the stratosphere. lince the lower limit of this range is the,. 4. Thus the lower the tropopause, theless limit of the resolving power of the electrop.,*, the total height of the cloud. Figure 6.25 microscope. To determine the fallout pat,:-.4 - illustrates- rougir estimates of some possi-,terns from a nuclear detonation,it is nec- bre Cloud, heights under "typical" 'condi- essary to icnow the distribution of the total tions.'v ; radioactiyity among particles of various 26'.= rbtatflbutiOn. of Radioactivity oithin.tM'.loiuis.Ffgure e 6.26summa. "iitektheldiitriliutiori of radioactivity within the, nticlear- cleud; You willnote: -Outt:Okojciinately-09%,ofthetotal activity in -;he cleUd and airy. 10%or lesS tri.--the stem sectioizjth the, bulls of the itetiyity-in tie base' of the :cloud. It-is :1Urther ,assumed that the',.hUllc,of there-- diOaCtiVe,Material that .4'ontributes .to .early:fallbut ,will, be' at'ort below about SNOOOleet: Aboyethiaaltittide the 01-'6- elear`iyilt.iiro4blY- 'be'ln..,4 finely divided 4.ill-,C-Oritribi.ite -most to' the

'WerldiOdefallotit,: . Ain.ount_., of :Radipactivity .014048,1:PAW* q2:08;::.410111, eX1001:1041' evidence radioactive parW

:officqopty We** (Ami- 6.2,0-Dhstribution of radiolketivity.- $ Mies.Knowledge in this area is still rather wind directions and speeds usually vary limited because of the difficulty in obtain- from one level to another, each particle ing large and repreientative samples of follows a constantly changing course, and radioactive debris-from a nuclear cloud. changing speed as- it falls to earth. The.' 6.28 Rate of Fall of Partieles.The par- rate of fall depends upon the particle size, ticles carried up into the atmosphere by a shape and weight and the characteristics nuclear detonation are acted upon by of the sir. The stronger the wind in each gravity and carriekby the winds. Since layer the further the particles will be car-

EFFECT OF PARTICLE SIZE (WIND di INITIAL HEIGHT 90,000 FT. ASSUMED CONSTANT) LARGE PARTICLES FALL FAST, LAND 60,000 FT. 01, CLOSE SMALL IN1RTICLES 111 30,000 FT. -11,1 %MIER N GROUND srittlig -EFFECT' OF HEIGHT (WiND a PARTICLE SIZE ASSUMED 90,000 FT. CONSTAN7) LOWER PARTICLES LAND SOONER, 60,000 FT. --111, SER UPPER PARTICLES FALL LONGER, LAND FARTHER , 30,000 FT.-

GROUND aa a a EFFECT OF WIND (PARTICLE SIZE ASSUMED CONSTANT)

90,000 Ft 'fko. . i7,z. I - , -STRONG 60,000 FT. WIND 0 PARTICLES LAND FARTHER, MORE SPREAD OUT 11 1 30,000 Ft, itI \\PARTICLES, LAND CLOSE WEAK WIND GROUND alba a _EFFECT OF VARIABLEWIND(PARTIdLESIZE a INITIAL 90,000 FT. 4-- 0 HEIGHT ASSUMED CONSTANT)

60,000-Ft PARTICLE:5 'MOVEMENT IS '.SUM OF ALL WIND FORCES 30,060 ft

GR0LIND: 'FIGURE 6.28,F'actors:affecting_diStribution of radioaltive partkles.

4 - ried in that layer. The faster the particle other sections of the cotentry. Southwes- falls, the less influence the wind will have terly. and northwesterly winds_are more on it and the closer to ground zero it will common. Above 60,000 feet, easterly winds I land. The 'higher the altitude at which it occur frequently in all seasons and are the begins to -fall, the longer it will be carried rule in summer over most of the United by the wind, and under most Conditions States. when the wirids at different altitudes do 6.32In deicribing- direction of fallout not oppose one another-the farther it will from the point of detonation (GZground travel. (See figure 6.28.) zero), the terms "upwind" and "down- 6.29 Meteorological Conditions.Winds wind" are often used. The "downwind" are the principal factor which affect the direction is the direlkion toward which the movement of the nuclear cloud. Even with wind blows, while "upviind" Means against the same type, yield, and altitude of deto- the wind. When applied -to falloutf the nation, different wind conditions willpro- terms upwind and downwind will apply to duce different falloutAnatterns of irregular the resultant or total effect of all the shape. The speed anorvertical shear of the winds through which the pgrticles have upper air winds will also affect the concen- fallen. An upwind component results from tration of railioactive materialon the the very rapid expansion of the cloud in all ground. A fallout pattern under conditions directions immediately after detonation. of strong winds aloft would differfrom The disturbances at the time of the explo- that of weak winds ih two ways. First, the sion will deposit radioactive material in strong wind would spread the material upwind and crosswind directions for rela- over a larger area tending to reduce the tively short distances from ground zero. concentration close to the source. Second, 6.33Since the direction of fallout is de- at a given distance the fallout wouldar- termined by winds up to at least 80,000 rive sooner and would have had less time feet, and since winds in the upper air to decay. frequently are quite different than winds 6.30 The United States hasa variety of at the surface, surface wind directions upper air winds. During the winter, spring, cannot be used as an indication' of direc.&"" and'fall seasons the United States Ninds tion of flow of high atmosphere winds. it it are pritharily the "prevailing westerlies." not at all uncommon ,te have east, south, By this it is.meant that the winds Oyer the or north winds at the snrfaceand westerly United States blow more frequently from winds aloft. . the west*n quarter than froth-any-other 6.34In considering the possiblearea of quarteA of thecompass. The westerlies in fallout, wind speed is as important as wind the middle latitudes become increasingly direction. Depending on particle size, the predominant with increasing heightup to direction determines the sector tp which -about 40,000feet. Nt 5,060 feet the winds they are carried; and the speedgoverns are from the western quadrant about half how far they will travel before coming to, the time; while at 30-40,000 feet theyare thearth. Wind speeds over the United "- from that quadrant about three-fourths of States generally are less in the summer the time. Above 40,000 feet, the percent- th4n in winter at all heights and above all, age of westerly winds again decreases. sections of the United States. The only' 6-.31The predominance of westerly exceptions would be during the paksage of wind direction changes with theseasons. hurricanes or tornadoes which produce Upper winds blow from the west more very strong surface winds in the warm offen during winter than duringsummer. seasons. This difference between seasons The increase in frequency of other direc- is greatest in the southeastern portion of tions in the summer is more pronounced in.the country, where winds become particu- the southeastern portion of the country, larly light and variable in the summer.. where direciions *bent/Ie.-variable at all buring the winter,upper winds along the levels. Along the Pacific Coast, the winds Pacific Coast generally have lower speed blow less constantly from the west than in than in any other section- of the United 92 117 , 5" v

States, Wind speeds increase with altitude 6.38 -Variation of the winds by day and from the surface up to a level between night has littO effect on factors that de- 30,000 and 40,000 feet!. Above this level termine fallout patterns. Winds a few they usually deciease in speed until at hundred feet aboveground fre-quently 60,000 to 80,000 feet they become rela- change 'from day to night, but those higher tively light. up, which have the greatest effect on the 6.35 The winds of greatest speed us- fallout lipeern, do not follow a daily cycle. ually occur between 30,000 and 40,000 feet, Cloudiness or fog alone are not believed to Winds exceeding .50 m.p.h. being the rule have a marked effeCt On fallout, although all over the country in winter and in the the combination of fallout particles -with northeast in the summer. In this layer,cloud droplets may result in a faster rate winds greater than 100 m.p.h. are at times of fall. Some cloud types also have upward experienced over all areas of the United and downward air currents. The down- States, but have been observed most often ward currents might tend to bring some of over the northeast, where they are found the radioactive debris down more rapidly about 25% of the time. In this northeast- than it would otherwise settle. ern area, winds of 200 m.p.h. occur frte- 6.39In addition to the wind, precipita- quently, with speeds -df 300 m.p.h. ob- tion in a fallout area will affect the radio- served on rare occasions. The high speed active deposition. Rain drops and snow winds usuallfr occur in narrow meandering flakes collect a large proportion of the currents within the broad belt of middle- atmospheric impurities in their, paths. latitude wOterly. winds, and are calledParticlesofradioactve'debris -are "jet-streams". "washed" or "scrubbed" out of tfle air, by precipitation. The result is that containi- 0.36 The strongest winds encounterednated material, which would be Spread_ by a falling particle have the greatest over a much larger area by the slower dry. proportional influence on its, total move- weather fallout process, is rapidly brought ments. The strongest winds are usually at down in local rain or snow areas. It is altitudes in the vicinity of 40,000 feet. conceivable that hazardsus conditions can These winds would largely determine the occur in rain Ateas where ordinary fallout gemraldirecti6nand length of the fallout estimges alight indicate a safe condition. Uleliottgit, all the winds- iito iit-Cre This sdrubbing reduces the amount of con- than twice that height could be tamination jeft in the air to fall out far- 6.37Fallout pAterns 'cher the -United ther States would probably differ in shape and. 6.40Terriiin features will also cause a extent. In the northern half of the country variation in the degree-of deposition. Hills, considerably longer patterns would be ex- valleks and slopes of a few hundred feet pected, spreading toward the east because would probably not have a great effect on of the strong upper air westerly winds.'the fallout radiation levels. Hoirever, The passage of low pressure areas would large mountains or ridges could cause sig- cause shifts from a more northeasterly to nificant variation in deposition by receiv- a more southeasterly spread of the fallout ing more fallout on the sides facing the pattern from one day to another. In the surface wind. This 'is true for both dry summer, particularly in the southern part weather fallout and "rainout". of the country\ a great variety of patterns might be expeeted with a broad irregular spreading in all directiOns in some cases, WORLDWIDE FALLOUT and elongated streaks in others. It should 6.41Worldwide fallout by definition is be remembered Islso that in an area where much more widespread than early fallout. several target cities are situated within diWorldwide fallout is that portion of the- few hundred miles of one another, fallout bomb residues which consists of very fine from more than one detonation might occur material that remains suspended in the af,the:Same Place. air for times ranging from days to years. Si These fine particles can be carried:over that most of the fine tropospheric fallout, large areas by the wind and may ulti- is deposited in a short period of weeks in a- mately be deposited on Parts of the earth fairly nat.row band andt encircling the remote from the point of burst. It should earth at the latitude of the nuclear deto- not be inferred from this term, however, nation. that none of the fine material is deposited 6.45For explosions of high energy yield in are'ainear the explosions nor that such ih the megaton range nearly all the bomb material is deposited uniformly over the debris will pass up throUgh the tropo- earth. sphere and enter the stratosphere. The 6.42 You will recall that early fallout is larger pellicles 'will be deposited locally important only when the nuclear burst for a surface or sub-surface burst, while occurs at or near the earth's surface so the very fine particles from bursts of all that a large amount of debris is carried up types can be assumed to be injected into intoethe nuclear cloud. Contributions to the stratosphere. Due to their fineness Worldwide fallout, however, can come from and the absence .of clouds and rainfall at nuclear explosions of all types, except such high altitudes, the particles will set- those so far beneath the sUrface that the tle earthward very slowly. Although ball of fire does not break through and agreement does not exist as to the mecha- there is no nuclear cloud, or those deto- nism that produces'observed differences in nated in outer space. With regard toi the 'worldwide fallout, it is now clear that non- mechanism of the worldwide fallout, a'clis- uniform circulation of stratospheric debris Unction must be drawn between the be- between the hemisphereS is a characteris- havior of explosions of low energy yield tic Mwor1dwide fallout. Also tto agreement and those of high energy yield. If the burst exists as to the residence tinle for,world- oecurs in the loNier part of the atmosphere vide fallout in the upper atmosphere, but theucleak- Cloud from a detonation in the-it appors to be somewhere between 1 to 5 kJ, oton range will not generally rise above y eaxi: the top of the :troposphere, conseqUent1y7 6.46During its long residence in the nearly all the fine particles present in the'stratosphere, the bomb residues diffuse bomb debris from sucli'explosions will re-,slowly but widely, so that they enter the Main in the troposphere until they aretroposphere at many points sover the evrtually deposited. earth's surface. Once in the troposphere, 6.43 The fine fallout particles front, the fine material behaves like that which re- troposphere are _deposited in a coinWex mained initially in that part of the atmos- way, COmplex, since varimis processes in phere, and is brought to earth fairly rap- addition to simple gravitational settling idly by rain or snow. are involved. The most important of these 6.47 An important feature of the strat- . processes appears to be the scavenging ef- ospheric worldwide fallout is the fact that fect of rain or other forms of moisture ,.the radioactive particles are, in effect, sto- precipitation. Almost all of the tropos- red in the stratosPhere witha small frac- pheric fallout will be deposited within two tion conttnuously dribbling down to the to three months after the detonation so earth's surface. While in stratospheric 'that bomb debris dpes not remain for very,storage, the debris does not representa long in the troposphere. direct radioactive hazard. In fact, during 6.44While the fine debris is suspended this time most of the activity of the-short- in the troposphere the major part of the lived isotopes decays away and some of the material is moved by. the wind at high activity of the longer-lived isotopes isap- altitudes. In general, the wind pattern is preciably reduced. Thus,tratospheric such that the debris is carried rapidly in worldwide fallout is a slow, continuous, an easterly direction, making a complete non-uniform deposition of radioactivema- circuit of the globe in some 4 to 6 weeks. terial oyer the entire surface of the earth, Diffusion of the cloud to the north and the rate of depOsition dependingon the soUth is relatively slow, with the result total amount of bomb debris still present , in the stratosphere, the season of the year 20.0 010 20 SO 40 SO 40 SO 40 SO 100 .10 120 40 40 MO .60 ao 40 .10, T.- arid the amOunt of precipitation. 1900 300

30 IMPRESENTATION 00 EARLY FALLOUT , MOO I HOUR '300 100 .6.48In a somewhat idealized situation, 30 it is to be exPected that, except for the very smallest particles which descend over ..Ja wide area,_the fallout of the larger particlea loll to 'earth forming a, kind of elon- 300 gated (or cigar shaped) pattern of contami- 100 .30 nation. The shape 'and dimensions will be 10 'determined by tbe wind velocities and directions At all altitudes kbetween the ground and the nuclear cloud. It should be RI HOUR emphasized that these _elongated Vi'llout FIGURE 6.50.Contours from fallout at 1, 6, and 18 patterns are ideali4ed, and an _actual fal- hours after a sui\face burst with a fission yield in lout pattern, will not conform ,to these pat- the megaton range (15 m.p.h. effective wind). Val- ,.terns. ' ues given are in roentgens per hour. . 6,49 AtapartieulartiMe.aher the deto. nation of a nuclear' weapon, the radiation contamination since the OcpOsure rate will '.POosure rate IS apt to be highest at fall off steadily over a.greater distence. ,:g-round zero; and Will decrease as the dis- , tante froth..ground, zero increases. This is , 6.51Consider fiftt, it'locatzon 3koil1es --because the. aMount -of fallout-,iper unit downwind from ground zero.,AVOne hour area is also- likely Ao be less. -There is after the detonation the observed expo- another factor that contributes to this de...sure rate is seen to be about 30 R/hr; at 6 crease irkexposure rate with increasing hours the exposure rate which lids be- -distancenthe explosion.-This-faCtOr is tween the contours for 1,000. and 300 R/hr time. The:later times of arrivatof the .has increased to about 800 R/hr; but at48 fallout -af these greater distances mean hours it is down to roughly 200 R/hr. The that, the fission products have decayed to increase in exposure rate from 1 to 6 hours 'IsOme extent while the particles were sus- ineiins the fallout was not complete one ._pendectin the air.; hografter detonation. The decrease from 6 6:50 Some *apt' the Manner in which to .18 hours is then due to the natural atallout pattern may develop over a large decay of the fission products. On theother _area during the .,period of several hours hand a total radiation exposure received .f.ellowinua-high-yield nuclear surface at the given location at one hour after the burst May be seen in Figure -6,50.. For explosion would be ielatively small be- aimplicity of representation,- the actual cause the fallout has only:just started to coMpIex wind pattern is replaced by Ian arrive. By 6 houri the total exposure could Approximately equivilent or effectibe reach over 3,000 R and by 18 hours a total -Wind of 15 miles per hour. Figure 6:50 exposure of some 5,0004R could have accu- -shows -a- numher of contours, for certain mulated. Subsequently, the total exposure arbitrary _exposure rates that could possi- would continue to increase but at a slower 14Y,hivebeettobserVed.on the ground at 1, rate. 6, and. 18 hoUrs + 4 H + 6; H + 18) 6.52Next, consider ci point 100. miles 4*§POtlYely After fhe explosion. It should ownwind from ground zero.----At one hour be-Underite,od- that the, yarieus exposure after the explosion the exposure rate, as Oites.ellange giadually from one contour indicated in Figure 6.50, is zero since the lineto the. next,'Sirritiarly, the last contour fallout will not have reaChed the specified 'line-Shown does noVrepresent the:limit of location. At 6 hourS the exposure rate is 19 _ 95 _

R/hr and at 18 hours about 50 Rthr.. The total (infinite) exposure will not beas great as al locations sloser to ground zero because the quantity of fission products reaching the ground decreases at increasing distances from the explosion.

UNCERTAINTIES IN FALLOUT PREDICTIONS 6.53Idealized fallout patterns are useful for planning purposes, but they are not blueprints of the actual, fallout pattern

that would occur. There are juit too many AfE MEAD uncertainties or variables involved in fallout, affecting both distribution, of early FIGURE 6.54b.Fallout patterns from nuclear test fallout and rate of decrease of radioactiv- detonation at the Nevada Test Site.

ity, to make precise prediction possible. . 6.54It is difficult to estimate the extent of the induced radioactivity because

.,"odifferences in type of weapon, the. :height i;f burstoknd the nattfre of the Sdif ° or other mateirial in which neutron born- ., bardment has caused 'radioactivity. 'Fur- jhermore, the eicistence of \unpredictable hot_ spots will affect local radiatin expo- sUie,rates, a§ will the nature of, the terrain (buildings, trees,etc., may reduce the average, radiation exposure rate above the _graund..to .70..or. 75- percent -Of- the value measured in open, fiat terrain); weather- ing (wind:may move surface-deposited fat- lout front 'one area to another or rain may Wash it into the soil); fractionization (any FIGURE 6.54c..Falha patterns trom nuclear tesi' detonation at the Nevada Test Site.

C: . _sne a, several processes, apart from radioactive decay), that results in change in the coMposition of the'radioactive weaPon de-

bris); fission products of differing ag9Land-, other.factors. These uncertaintiesor ..Tari- ables mean that the cigar-shaped fa lout patterns are idealized, not necessarily "real. Tb se,e film the idealized pattern differs from an actual pattern, refer to Fig- Orei.a through 6.54c whi`ch sh4w fill- lout' Pa erns ,from actual test detohations M 4 e istevada Test Site. These patterns - were teloped from monitored Teadings taken s ortly after the test shots:

6.55So far we have examined' the fal- ,

FIGUR? 6.5-4.4allout patterns from nuclear test lout problem in general terms without , *:detonation at the Nevada Teit Site. trying to show the magnitude ot the sittta-, _ . . tion, that cotild eicrst if theentire. nation -should be attackedt The'map in Figure 6.55a illustrates .an ass\umedhypothetical - nuclear attack. Each circlerepresents a 20 megatob surface PxplOsion. Thereare 50 of these. 'Each square representsa 10 mega= ton surface burst. Thereare 100 of these. Each triangle representsa 5 megaton burst and there are also 100of these. In . this hypothetical attackthere are 256 weapons dropped or& 144 differenttargets which include military,industrial and pop- tjlation objectives. The toAlyield of these '250 weapons is equivalentto 2500 mega- FIGURE 6 55b.HypotheticaI ttack,.1-1 +1situation. tons or 2.5 billion tons of TNT! Exposure rates exceed )0 4tIhr. 6.56Figure 6.55b shows theareathat would bp affected by falloutand the theoretical levels of radiation one'hour after the attack. The falloutareas would be 30 to 50 miles long, dependingupon wind speed and In the center ofthese areas the levels of radiation could begreater than 3,000 R/hr at H + 1.- , 6.57Figure 6.55c illustrates the situation 6. hours afterttack. Fallout would have sprea'cl oye'r out 40% of the national land area. Hoviever,the radiation FIGURE 6.55c.Hy pothetica1 attack, H +6 situation. levels would have decayedby ap.proxi- Exposure rates exceed 1 R/hr., mately a tactpr of ten. Theexposure rates in these areas wouldrange from one R/hr Nowlie7 Ae1;03- along tbe border to perhaps400 R/hr in ,02011, -_-megasmirrr,, the-center. Figure 6.55d iillustratesthe areas that would be affected-by falloutone NAL:110-VAP01,11 Pea day after attack. Approximately70% of *yea41:au.AVIIVA the country's totalarea would be covered by fallout exposure ratesgreater than 0.2 R/hr. About 18% of the.lb.ndarea would have a very Serious falloutcondition.

FIGURE 6.55d.Hypothetical attach, H +24 sitaution. Exposure rates exceed .2 R/hr.

6.58Shortly after the first.day radioac- tiVe decay would ileginto predominate over further HPposition of fallout The boundaries of these falloutareas would gradualiy shrink. Figure 6.55e illu,strateg thesituation orie 'week after attack during whichtime the radioaictiveareas would hai.4e. peen decreasing in size ana theexposure rates decreasing as a retult ofdecay. Only about F1GGRE15.55a.Hypothetical attack pattern. one-third of thee nation"sarea would be 92 D7 Itame the ground zeros and thesame weapon yieldsbut, based on the weather ofJuly,12, 1957. You will note that theaxis of fallout deposition ofmany locations has shifted by more than 12 4 degrees.On another day. the wind could swingin any other direction and tum safeareas on these maps into areas ofextreme fallout dangar.

FALLOUT FOREdASTING FIGURE 6.55e.Hypothetical attack,H +1 week 6.62 We have seen thatone of the most sitirtion. Exposure rated exceed .2 R/hr. significant factors affecting thedispersion of fallout Was the wind. Wealso saw that data can be obtainedon wind direction and speed at various altitudes.Since a major inflUenceon fallout' is .one about which considerable dataare known, it ena- bles us to predict withsome degree 'of accuracy the probable pattern of fallout dispersion. The 'requirementsof fallout

FIGURE 6.55f.Hypothetical attack, H.+2 months 0 situation. Exposure rates exceed .2 R/hr.

covered by falloutexposure rates exceeding 0.2 R/hr. This reductionin exposure rate would continue.' Two montfisafter attack, the situation mightexist as illustrated in Figure 6.35f. We wouldfind .only isolated elongated islandswhere.the levels FIGURE 6.60.Hypothetical attack,fallout pattern of radiation would exceed0.2 R/hr. for winds.of June 28, 1957. ,.6.59It is emphasized that thistraining exercise represents justone attack pat- , tern applied to the wincIS and weather of one day. Had a different attack pattern beenA"elected or the weather foranother day, the fallout situation wouldhave developed quite differen9y. 6.60 To illustrate the effectsof differ- _ ent wind patterns on a hypothetical nuclear attack; figure 6.60 showsa fallout prection for a 156 weapon-384megaton attac -\nsing the wind. cOnditionsthat ex- on June 28, 1957, 6.61Figure 6.61 sh-ows the theoretical FIGURE 6.61.HYpothetical attack, falloutpattern fallout from the identical attackpattern for winds of July 12, 1957. DP 93 prediction 'frornwind direction 'and slieed For example, at Lynchburg, fallout woold . are two: accurate data and current data..be forecast to arrive about one hour after Both of these conditions are met by the detonation. . network of rawin observatories estab- Information provided thkorecasts is lished by the United States and Canadian limited to areas that may be coverpd ,by . Weather Services. fallout sand the approximate times of fali, 6.63 The purpose of preparing fallout lout arrival within the forecast area. Pre2 forecast plots is to provide graphic esti-dieted radiation levels or exposure rates mates of areas that are likely( to receive are not includ-ed in t7he forecasts. fallout and the approV,mattktime'of fallout 6.64Meteorologic.al data for the con- arrival. Figure 6.63 illustates a fallout struction of fallout forecast plots are avail- forecast plot. The area inside the heavy able to all levels of government in the 'UP shaped pattern and the dashed three- form ot "DF" messages which arp trans- hour line represents land which could be mitted by teletype over the national covered with fallout within three hours of weather service network. Data points are a nuclear surface detonation upon the city showq on Figure 6.64. Arrangemeuts for 'of Roanoke. The dash'ed One-hour and two- the receipt of D'F messages should be hour lines represent fallout tar:rival times made to iupport operations iri the event of and provide for forecasting Mllout arrival a fallout emergency. at various places within the forecast plot. 6.65 The Deferise Civil lfreparedness

FIGURE 6.63.--A fallout forecast plot. 94 AP

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FIGURE 6.64.DF data points.

:Agene'y has prepared.a manual of detailed instructions on the construction REFERENCES and use of fi fallout forecasts. This manualis entitled Tile Effects of NuclearWeapons.Glas- "Users ManualMeteorolokicarData for stone, Sainuel, 1964., Radiological Defense," '(FGE-5.6/1).The Fdllut Firom. Nuclear Tests.ilearings Manual explains the "DPP'message for- before the Special Subcommitteeon Ra- mat, giNtes instructionson preparing fal- diation of the Joint Committee lout forecast on Atomic areas, and ill'ustrates how to Energy, Congress of theUnited States, , estimate falloutAIrrival timefor opera- May 1959. tional Use. The manual may be obtained Use.rs MandalMateorologOal DIta through regular civilpreparedness- for nels. RadioloOcal Defense,FG=t7,5.6/1,July . 1970.

1 0.0 - 95 CHAPTER 7

EFFECTS OF NUCLEARRADIATION EkPOSURE

We have learned thatnuclear radiation is a form of energy:which materials would stop the"something". has the power to Eventually, he tried placing damage living cellsor tissue. In thii chap- a 'thin sheet ter, our ol?jective is to explain: of lead between the tube andthe crystals _and found that it didstop the passage of WHAT are the effectselfnuclear radia- that something. Tryingfurther experi- tion ments, he picked upa small lead piece and held it up before the tube. HOW are they produced Ile was stag- gered to see that not onlydid the round We are going to takea look into a human dark shadow of the diskappear on the cell and see what happens whenit is sub- screen of barium crystals, BUT THAT.HE jected to nuclear radiation,what kind of COULD DISTINGUISH THEOUTLINE damage is produced and the effectsof this OF HIS THUMB ANDFINGERS. Not damage. And there is somethingelse we only that, but withinthis outline were will learn, too, something that i;VITAL in darker shadows: THEBO,NES OF HIS -effective RADEF work: HAND. Theie phenomehawere so con- WHAT is the toleranceof the human trary to common sense, thatRoentgen body to nuclear radiationhow worked in secrecy, afraidthat he might be discredited for suclh "unscientific" much can we standhowlong work. can we stand it Even his best friendswere kept in the dark. When one insistedon knowing what was going on, Roentgen said, "I havedis- INTRODUCTION covered something interesting,but I do '7.1Late one November not kno* whether or notmy observationS afternoon in are correct." 1895, as the *German'physicist Wilhelm Roeritgen was sendingan electric current 7.2Finally, after continuedexperi- at high voltage througha vacuum tube, he ments including the firstX-ray photo- noticed A welak light thatshimmered on a graph (taken of his wife'shand), Roentgen little bench he knewwas located nearby. realized that he must tellthe world of his It seemed as if the sparkof light insidethe findings. He reported allhis experiments, tube was being reflectedin a mirror. Strik- stating that the phenomenawere caused ing a mata, hesaw that a screen with by some form of invisibleradiant energy. some barium salt crystalson the bench He called thisenergy 4'X-rays", the "X" was shining with fluorescent'brilliance. standing for unknown: _Later, he held a piece ofpalier, then a '7.3The story 'broke in playing card, and thena book'between the the Vienna Presse on January 5,14896, and soon scien- tube and the screen. Hewas amazed to see tists all over the world, that, even with the bookplaced in front of including Thomas the tube, THE CRYSTALS Edison, were excitedlyexperimenting with STILL BE-Ithis new kind ofray. The boon to medicine CA'ME FL'UORESCENT. Iiespiteevery of X-rays, or Roentgen-rays law of science (as thenunderstood) he had as they ,were to admit it: SOMETHING, later called, wai obvious:examining bro- some unknown ken bones and- fractures;locating tumors or-"X" quantity,was passing right through or other abnormalities. For the solid book..He then triedto see if other some, X-rays were even a source of amusement,a hobby 101 97 or playtoy. In 1896, the following adver- salts gave off .penetrating rays, similar in tisement appeared in the magazine Scien- operation to X-rays. Later, Pierre Curie tific American: and his wife, Magrie, tried to find the sub.- "Portable X-ray apparatus for physi- stance responsible for the radiation that cians, professors, photographers and Becquerel had observed. It was Marie students, complete in handsome case, Curie who termed thig activity RADIOAC- including coil, condenser, W/o sets of TIVITY, to which you wereAtroduced in tubes, battery, etc., for the price of $15.00 net, delivered in the United Chapter 2. After intensive work, the Cur- rrIStates with full guarantee." ies found two new radioactive elements, "polonium" and "radium". From repeated ' Not understanding the nature of X- overexposures in her work with radioae- MOP., ras, those early users of this new form of tive substances, Madam Curie suffered ra- energy did not treat it with respect. It was diation injury and subsequently died from even customary to use the hand as a fluo- the delayed effects of radium damage. Her roscopic test object in controlling the qual- daughter, Irene Curie, carried on the ity of the roentgen or X-rays. Soon, those mother's wprk, and she too died from over- who were exposed to continual large.doses exposurerto radiation. of X-raysr patients, doctors, students, sci- '7.8What happens when living tissue is 6 entists alike, began to notice painful effects. One, Dr. Emil H. Grubbe pf Chicago,-bombarded with radiation? Why does it said: "I had developed dermatitis on the cause so muS havoc to the body? These, back of my left hand which, was so acute and other questions will be answered in that I sought medical aid." The "dermati- subsequent paragraphs. tis" was a radiation burn, and Dr. Grubbe's fingers and hands had been so NUCLEAR RADIATION INJURIES badly burned by the X-rays that subse- 7.9Each advance in man's power over quently they were amputated piecemeal nature has brought with it art. element of as the damaging effects of ;overexposure danger. X-ray and nuclear radiation is no spread. a exception. We adopt a policy of acceptable 7.5Since it was noticed that exposure risk in every facet of our lives., Society to X-rays caused the hair to fall out, some must decide what risk it will accept ic the concluded that X-rays were a good way to use of nuclear radiation. The ,scieAtist remove excess hair. One example, cited by must clearly, set forth the hazards. Dr. W. E. Chamberlain of Temple Univer- The prithary biological-effect of nuclear sity, shows what could happen: radiation on life is in the cell. The normal A doctor in a small town heard that X- life process in a cell uses a very small rays make hair fall out. His comely little_ secretary complained of having hairy amount of energy wit'h a high degree of arms. Apparently unaware of the poten- self-regulation. When ionizing radiation tialities for harm, the doctor adminis- strikes a cell it disrupts the living process. /tered X-rays. with his portable radi- The specialized parts of a cell, such as the ographic machine. Horrible X-ray burns genes, are damaged not onry by direct hits developed, and in due time the young but also by the chemical poisons produced lady's arms had to be amputated. by ionization of the cell fluid. Many'Years 7.6 By 1922 it was eitimated that 100 ago radiologists .noted that the number of radiologistsad perished from overexpo- cells damaged by a given exposure to ra- sure to radiation. Continued experiments diation is a simple function of the number clearly showed that all living tissue could of living cells present. In other words, the be destroyed provided it was bombarded number of cells damaged per unit of dose with .a sufficiently high dosage of radia- is constant. The number of cells in which lion. genetic damage occurs is also a function of 7.7 A few months after Roentgen dis- dose. cOVeredl-rays, the French scientist Henri 7.10 A higher plant or animal such as Becquerel found that certain uranium man consists of many cells. Higher forms 98 1 02 of life are a society of specialized and material. For sOft tissue, interdependent cells..Radiation the differende damage to between therep and the rad is small, and one organ or group of Specializedcells can numerical values of disturb otherorgans and weaken the absorbed dose for- merly expressed inreps are essentially. whole organism. Man'slife functionsare carried out within unchanged when convertedto rads. a very iiarrow 'range of 7.13 temperature, air, nutrients,water and ra- Although all ionizingradiations diation. This cooperativeaction of cells are capable of producing similar biological and tissues makes higher effects, the absorbeddose (measured in forms of life rads) which will produce much more Nulnerableto radiation than a certain effect low'er forms of life. may vary appreciably fromone type of Furthermore, individu- radiation to another. This als of the same speciesreact differently to difference in a radiation dose justas people react differ- behavior is expressed by.means of the ently to a cold. , "relative biologicaleffectiveness" (or RBE) of the particularnuclear radiation. The RBE of a givenradiation is definedas RADIATION UNITS the ratio of the absorbeddose in rads of 7.11 'The radiationunit is known as the gamma radiation (of a specified energy)to roentgen. By definition, itis applicable the absorbed dose inrads of the given' only to gamma yadiation having thesame biological ef- rays or X-rays and not to fect. other types of ionizingradiation, suchas alpha and beta parliclesand neutrons. 7.14 The value Of theRBE for a partic- Since the roentgen(refers to a specific ular type of nuclearradiation. depends result in air accompanyingthe passage of upon several factors, including tile,dose* an amount of radiation through-air,it does rate, the energy of theradiation, the kind not imply any effectwhicb it wouldpro- and degree of the biologicaldamage, ahd duce in a biologicalsystem. Because of the nature of the organismor tissue under this, the roentgen is,strictly speaking,a consideration. As faras nuclear weapon measure, of radiation "exposure."The ef- are concerned,, the important criteriaare fect pn a biologicalsystem, however, is disabling sickness anddeath. expressed in terths ofan "absorbed dose." 7.15 With theconcept of the RBE in By comparing theactual biological effects mind, it is now usefulto introduce another of different types ofionizing radiation, it unit, known as the 'Irem,"an abbreviation is possible toconvert the aksorbed dose of "roentgen equivalentmammal (or into a "biologicallysignificant dose" which man)." The rad isa convenient unit for provides an index of thebiological injury-*expressingenergy absorptiOn, but it does that might be expected. not take into account the of the particular biological effect 7.12 The absorbed nuclear radiation. ab- dose of radiation sorbed. The rem,however, which is de- _was originally expressed interms of a unit . called the "rep," the fined _by: dose inrems = RBE X dose in` name being derived rads, provides an indication'of the extent from the initial letters of"roentgen equivalent physical." It of biological injury (ofa given type) that was used to denote a would result fromthe absorptiOn ofnu- dose of about 97 ergs ofany nuclear radiar clear radiation. Thus, tion absorbedper gram -of body tissue;7 the rem 'is a dose unit of biological effect,whereas the rad is however, for variousreasons this unit has a unit of absorbed proved to be some'what energy dose and the unsatisfactory. In roentgen (for X or ganimarays) is one of order to avoid difficilltiesarising in the exposure. use of the rep, a new unit ofradiation absorption, called the "rad,"has come into general use. The rad is 4 2 Because I roentgen exposure kives defined as the about I rad absorbed dote in tissue for photons of intermediate absorbed 'dose of energies (0.3 to 3 MeV), the absorbed any nuclear radiation dose for gamma (or X-) rays which is accompanied by is often stated, somewhat loosely.In the liberation of "roentgens " However, for photonenergies outside the range from 0.3 to 3 MeV, the exposure in roentgens 100 ergs of is no longer simply related to the energy per gram of absorbing absorbed dose in rad.

99 7.16All radiation Capable of producing 7.19 The importance of making a:dis- ionization (or excitation) directly or indi- tinction between acute -and chronic expo- rectly, e.g., alpha and beta particles, X- sures lies in the fact that, if the dose rate rays, gamma rays, and neutrons, cause is Tot, too large, the body can achieve radiation injury of the se general type. partial,recovery from some of the conse- However, although theetcts are qualita- quencei of nuclear radiations while still tively similar, the varidis radiations differ exposed. Thus, apa:rt from Certain effects in the depth to which they penetrate the mentioned later, a larger total gamma- body and in the degree of injury corre- radiation dose would be required to pro- sponding to a specifthd amount of energy duce a certain degree of injury if the dose absorption. As seen above, the latter dif- were spread over a period of several weeks ference is expressed by means of the RBE.. than if the same dose were received within a minute or so. 7.17 The RBE for gamma rays ii ap- 7.20All living creatures are always ex- proximately uinty. For beta particles, the posed to ionizing radiations from various RBE is also close to unity; this means that natural sources, both inside and outside for a given amount of energy absorbed in the body. These are chronic exposures con- ' living tissue, beta particles produce about tinuing for a lifetime. The chief internal the same extent of injury within the body source is the radioisotope potassium-40, as do X-rays or gamma rays. The RBE fOr which is a normal constituent of the ele- alpha particles from radioactive sources ment potassium as it exists in 'nature. have been variously reported to be from 10 Carbon-14 in the body is also radioactive, to 20, but this is believed to be too large in but it is only a minor source of internal most cases pf interest. For nucleafweapon radiation: Some potassium-40, as well as neutrons, the RBE for acute iadiation in- radioactive uranium, thorium, and radium jury is now taken ael.0, but it is apprecia- in varying amounts, is also,prsent in soil bly larger where the formation of opacities and rocks. The so-called "cosmic rays,' of the lens of the eye (cataracts) is con- . originating in .apace, are another impor; cerned. In other words, neutrons are much tant source of ionizing radiations in na- more effectiVe than gamma rays in caus- ture. The radiation dose received from ing cataract's. . . , , these rays increases with altitude up to- 7.18In considering the possible effects about 90,000 feet; at 15,000 feet, it is more pn the body of gamma radiations from than five times as great as-at sea 'level'. N,external sources, it is necessary to distin- The high radiation levels encountered in guish between an "Aute" (or "one.shot")the Van Allen belts at much higher alti- exposure and a "chronic" (or extended) tudes do not contribute to the background exposure. In-an acute exposure the whole radiation on earth. ,radiation dose is received in a relatively shaft interval of time. This is thecase, for GENERAL RADIATION EFFECTS example, in connection' with the initial nu- 7.21The, effect of nuclear radiations on clear radiation. It is not possible to define living organisms -depends not only on the an acute doie.,preciselY, but it may be total dose, that is, on the amount ab- somewhat arbitrarily taken to be the dose sorbed, but also on the rate of absorption, received 'during a 24-hour period. Al- i.e., on whether it is acure or chrOnic, and though the delay.ed radiationS from early on the regipn and extent of the body ex- fallout persist for longer times, it is during posed., A few yadiation phenomena, such the first,day that the main exposure would as genetiE effects, apparently depend 'pri- be received and so it is regarded as being marily upon the total dose received and to

acute. On the other hand, an individual a lesser extgnt OD the rate of delivery. The a& entering a'fallout area after thefirst dayinjury; caused by radiation to the germ or so antriemaining for some time., would cells under certain conditions appears to be consiilered to have been subjected to a be ctimuLative. In the- majority of hi- chronic.exposure._ stanceg, however, the biological effect of a a 100. -194 given total dose of radiationdecreases as sources. These include a few laboratory the rate of exposure decreases.Thus, to accidents involving -cite an extreme case, 1,000 small number mof hu- rems in a single man beings, whole-body irradiation ,used in dose would be fatal.if the wholebody were treating various' diseases and exposed, but it would probably malignan- not have cies, and extraPolation to mariof observe:- any noticeable external effects' in the Ma- tions on animals. In addition, jority'r of persons if detivered detailed more or less knowledge has been obtained froma care- evenly over a period of 30years. ful study of over .250persons in the Mar- 7.22Th,e injury caused bya certain shall 'Islands, whowere accidentally ex- dose of radiation will dependupon the posecl tonuclear *radiatioh from fallout extent and part of the body_plat is ex- following the test explosionon March. 1, posed. One reason for this isthat *hen the 1954. The exposed individualsincluded exposure is restricted, the unexposedre- both Marshallese anda small group of gions can contributb to therecovery of the Amefican servicemen. The whole-bodyre- injured area. But if thewhble body is'diation doses ranged from relatively%mall exposed, many organ'sare affected and values (14 rems), which produceno recovery is much more difficult. obvious symptoms, toamounts (175 .rems) 7.23Different portibns of the .body which caused Marked 'changes inthe show different sensitivitiesto ionizing ra- blood4orming system'. diations, an'a thereare vaiiations in de- 7,26 gree of sensitivity. among individuals. o single source of data directly In',yields the relationshipbetween the physi- general, the most radiosensitive partsin- cal dose of ionizing radiation clude the limphoid tissue, and the clini- bone marrow, cal effeet in man. Hence,thereiiino com- spleen, organs of reproduction,and gp- plete agreement concerning trointestinah tract. Of intermediate the effect as- sensi- sociated witli a specific dose-ordose range. , tivity are the skin, -lungs,and liver, Attempts in the past have whereas mustle,nerves, and adult bones been made to are title least sensitive. relate particul(r symptomsto,certain narrow ranges of exposure; however, thedata are incomplete and associated with mahy EFFECTS OF ACUTE RADIATIONDOSES complicating facto,rs that o- make 7.24Befgrbthe nuclear bombingsof Hi- interpretation difficult.For iostance, the roshima and Nagasaki, radiationinjury observations in Japanwere very sketchy was a rare occurrence and relativelylittle Until 2 weeks following theexposures, and 'was known of the. phenomenaassociated the people at that time we'res'uffering with whole-bodyexposure and radiation from malnutrition andpreexisting bacte- injury. In Japan, howevyr,a large number rial and paraSiticinfections. Come- a individualswere eiposed to doses of quently,, their sicknesswas often erro- radiation ranging from insignificantquan- neously attributed to theeffects of ioniz- tities to amounts Which provedfatal. The ing radiation when Auch'wasnot necessar- effects were often complicate'dby -other ily the case. The existingConditions may injuries and shock,so that the symptoms have been aggravated aythe radiation, of radiation sickness couldnot always be but to what extent it isimpossible to esti- ,isolated. ,Because of the greatnumber of mate in retrospect., patienti and t,he lack offacilities after the 7.27In attempting 'to relate theradia- -.exPlosions, itwas impossible to make de- tion' dose to the effecton man, it should be tailed observations and keepaccurate rec- mentioned, that reliable,information has ords. kevertheless, certainimportaht con- been obtained for dosesup to 200 rems. As clusigns have been drawnfrom Japanese the dose increases from 206to 600 reins experiende with regard to theeffects of the data from exposed humansdecrease nuclear radiation on the humanorganism. rapitlly and must besupplemented more and more by extrapolations 7.25 based, on ani- Since 1945, prther informationoh mal studies. Nevertheleds, -the this subject has been gathered conclusions from other drawn can be accepted witha reasonable: 101 Uzi -

- 10070 1,000 REMS THERAPEUTIC RANGE OVER 1,000 REMS LET/4AL RANGE 1 0 TO 100 REMS 100 TO 200 REMS .200 TO 600 AEMS 600 TO 1,000 REMS 1,000 TO 5,0,00 REM4OVER 6,000 REMS RANGE SUBCLINICAL RANGE CLINICAL THERAPY EFFECTIVE THERAPY PROMISING THERAPY PALLIATIVE SURVELLANCE . .

INCeENCE OF 100 REMS 5% NONE 300 RE MS 100% 100% 100% VOMITING 200 ROA 50% . .. .. ; DELAY TIME - 3 HOURS 2 HOURS 1 HOUR . . ''`ap MINUTES 1 . , .... GASTROINTESTINAL CENTRAL NERVOUS HEMATOPOIETIC TISSUE LEADING ORGAN NONE TRACT. SYSTEM

, DIARRHEN FEVER SEVERE LEUKOPENIA; PURPURA; HEMOR- CONVULSIONS; CHARACTERISTIC MODERATE DISTURBANCE OF NONE RHAGE; INFECTION. TREMOR; ATAXIA; LEUKOPENIA ELECTROLYTE SIGNS EPILATION ABOVE 300 REMS - ' LETHARGY. . BALANCE. I t . . a . CRITICAL PERIOD ' ,- 4 TO 6 WEEKS TO,8. 14 DAV I TO 48 HOURS POST-EXPOSURE -

- / REASSuRANCE; BLOOD TRANSFUSION; CONSIDER BONE MAINTENANCE OF THERAPY REASSURANCE -----ThEMATOLOGIC MARROW TRANS-, ELECTROLYTE ., (I, SEDATIVES ANTIBIOTiCS. SURVEILLANCE. PLANTATION. BALANCE. .., - -4-

PROGNOSIS EXCELLENT EXCELLENT G000, GUARDED HOPELESS , , s d)NVALESCENT PERIOD ',NONE SEVERAL WEEKS I TO 12 MONTHS' LONG - 96 70100% INCIDENCE OF DEATH NONE NONE OTO 80% (vor) 80%70100% (vor) .

. _ - - 2 MONTI1g 2 WEEKS 2 DAYS 'DEATH OCCuRS WITHIN , ., , "-7/ CIRCULATORY RESPIRATORY FAILURE; HEMORRHAGE; INFECTION .CAUSE OF DEATH ' COtLAPSE . , BRAIN EDEMA. - , . , ... fAl.LIATIVE-AFFORbING RELIEF; BUT NOT A CURE. PURPURkLIV1D SPOTS ON THE SKIN OR MUCOUS MfiMBRANEe HEMATOPOIETIC TISSUE-BLOOD FORMING TISSUE. EOEMA-ABNORMAL ACCUMUL TION OF FLUIDS N TME TISSUE LEUKOPENIA-REIDUCTION IN NUMBER OF WHITE BLOOD CELLS (Ieukocytos)

. . FiGultE 7.28.Summary of effects from brief nuclear radiation exposure. ".

. . degree of cOnfidenee. Beyond 600rems, of recovery arb sopoor 'that theralv nIaly- however, observations onman are so spo- be rest 'cted laigely,to p-alliative mess-. radic that the relationship betweendose uies. Its of interest however, to*subdi- and biological ;Wed' must 'be inferredor vide thileth'ai range intot two, parts in' conjectured alinoit entirely fromobserva- 'which the chariipteristic,clinital effects tions made on animals exposed toionizing are. different. Although the dividing line radiations. has been somewhat arbitrarily.setat 5,000....: 7.28 With th.f, foregoing factsin mind, 'reins in -Figure'.1.28, humandata are so Figure 7.28 is presentedas the best avail's- limited, that this doseleVelmight well ble -Summary of the effectsof v.arious, have any value from 2,000to 6,000, reths. whole-body dose rangesvof ionizingradia- In the renge from 1,00Q to(roughly) 5,0,0b tion on Yunnan beings. Below 100 . rems,. the rems, the pathQ115gical. changes' are'most response is almost completely subclinical; marked' in the gastrointestinal'tract, that is to say, there isno sickness requir- whereas in the range above 5,0Q0'rems, it. ing special attention. Charles may, never- ,is .the, central neivous systeni whichex- theless, be occurring in the blood,as will hibitS the major injury. 300.' be seen later. Between 100,and1,000 reins is_the_rang The syperposition of .radiationef- , . erop fects upon irMio-s-Ifom othercausearnay medical treatment, will besucce sful at beexpected to. result in the lower end and an increase in tne: may be successful at the number of cases of shock. Foraxainple,,the upper end. The earliest symptoms of-radia- combination of sublethal nucleaeradiation tion injury are.nausea andvomiting, exposure and moderate thermal burns will :- which may commence within about1 to 3 produce earlier antlmore severie shock hours of exposure, accompaniedby discom- than would the comparable' burns . fort (malaise), loss of appetite, and 'alone. fatigue. The heling of woundsorall kinds will bk. The most significant, althoughnot imme- retarded because of the diately obvious, effect in the .susceptibility toN range under secondary infection 'Accompaffyingradia- ;consideration, is that on the hematopoietic tion injury and for other reaions. tissue, i.e., the organs concerned In fact, w,h the infections, which could normallybe ;dealt formation of blood. An ,importantmanifes- -with by the body, *Mayprwe fatal in sucii tation of the cbanges in the functioningof- cases. these organs is leukopenia, thatis, a de- I . .cline*in the number of leukocytes(white CHARACTERISTICS: blood.cells). Loss of hair (epilation) willbe OF ACUTE WHOLE-. apparent about 2 weeks orso after receipt BODY RADIATION INJURY ',"7 of a dose exceeding 300 ., rems. 7.32Single doses in.the...rangeof from 7.29'Because of the increase in these- 25 to 160 remsover the' whoje body will verity of the radiation injury andthe vari- produce nothing othei thanblood changes. ability in response to treatmentin the These/hanges do not usuallyoccui- below 4- range. from 100 tO 1,000 reins, it isconven- this range arid arenot produced consist- ient'to subdivide it into threesub-sections, ently at doses below 50rems. Disabling as shown in Figure 7.28. For whole-body sicknessi,does notoccur ancrexposed,indi- -exposures from 100 to 200 reins; hospitali; viduals should be ableto proceed With ,..zation is generally not required, butabove their usual duties.,Thus, for, , 200 rems admission to.a. hospital is neces- doses of 25 to 100 reins': ssary sOthat the patient no illness may receive such ExpOsure of the whole body treatment.as,.maly be indicated. Up to 690 tO a radiation dose in therange of 100 to ZOO rams, there is reasonable confidence in the rems result in a tcertain amount ! clinical pirentsand/appropriate therapy, of but for doses in exc'esa of this illness but it will rarelibe fatal. Doses of ambunt this.`m,agnitude were 'common there is Considerableuneertainty and vari- in Hiro-, ability in response, shima and Nagasaki,-particularly among persons who were at some distande from 7.30 Beyond 1,000 rems, the prospects the nuclear explosion.Of the 267 individu- 107 103 ara

a 4. als accidentally exposed to taIlout in the d nghih the patient feels relatively Marshall Islands forlOwing the test explo- ..I'llyugh important changes are oc- sion /of .March 1, 1954, a group.4f 64 re- cuvilig in the blood. Subsequently, there ceived radiation doses in this range. It is a return of symptoms, including fever, shquld be pdinted out that the exposure ofr diarrhea, and a step-like rise in tempera- the Marshallese was ,not strictly of ae ture which may be due te accompanying acute type, sinte it extenaed over a period infect' Thus, for of some 45 hours. More.than half the dose, doses of 200 to 1,000 rems : survival however;was received within 24 hours and possible :the observed effects were similar to those . 7.36 Commencing abont 2 or 3 weeks to be Orpected from an acute e-xposure of after exposure, there is a tendency lb the same amohnt. Thus, for bleed into various organs, and small hem- doses of 100 to 200 renis ; slight or no orrhages under the skin (petechiae) are illness observed. This tendency may be marked. 7.34The illness 6.91 radidtfon%doses'in Particularly common are spontaneous.. this range does not presents serious prd6- bleeding' in the rbouth qnd from the lining lém in that moSt p,stients-will suffer little of the intestinal fract. There may be blood more than discomfort and fatigue and oth- in the urine dve to bleeding in the..kidney. ers may.d have no symptoms at all..There The hemorrhagic tendency depends may be some pauses and vomiting on the mainly upon, depletion of the platelets in first day or so folloWA, irradiation, but the blood, resulting in defects in the blood- subsequently there is a so-called "latent Clotting mechanism. Loss of hair, which is peri2c1,4 up to 2 weeks Or more, during a 'prominent consequence of radiation ex- which the patient has no disabling illness posure, also starts after about 2 weeks, and can proceed with his regular occupa- immediately following the latest period, tion. The usual symptoms, such as loss of for doses over_300 rems. (See Figure 7.36.) appetite and malaise, may reappear, but if they do, they are mild. The chhnges in the character df-the blood, which accompany radiation injurx, become significant dur-. ing the latent period and persist for some

,time. If there are no coMplications, due to other injuries or to infection, there-will be. . recovery in essentially all.cases. In general, the more'severe 'the .early stages of the radiation sickpess, the -longer will be the process of .recovery. Adequate care ,.dnd.the use.,of antibiodei, as may be,

catecrclinically, can greatly expedite-corn- , ..plete recovery of the small proportion of

more serious cases. . 7.35 Por do4es between 200 -ane1,000, rems the probability of survival is.good at the lower..exkil-orthe range but POor at the upper end. The initial'symptoms are similar to. those commOn hi- radiation injury, namely, nausea, vomiting, diarrhea, loss of appetite, and malaise. The/rarger the dose, the sooner will these symptoms develop, ; generally during- the initial daSr of the expo'Sure. After. the first day or two the* symptomsdisappear and there may be latent period of several days to 2 weeks FIGURE 7.36.Epi1atioq due to radiation exposure. 104 6 rl ta,1/43 7.37Susceptibility to infectionof wound's, burnsrand Other excitability, ataxia (ladk of muscufarcoor- Lesions; can bea dination), respiratory distress, serious complicating factor.This wouldTe-- and inter- spit to a large degree mittent stupor. there isalmost immediate from loss of the incapacitation, and death is white blood-cells, anda marked depression certain in. a in the body's immunological few hours toa week or so after the,acute procesg. For exposure. If the dose is in the example, ulceration aboutthe lips maY range from commence after the latent period 1,000 to roughly 5,000rems, it is the gas- and trointestinal system which-exhibits the spread from the maiththrough, the entire earliest severe clinical gastroinestinal tract in effects. There is the the:termina.L.stage usual vomiting .andnausea followed, in , of the sickness. The multiplication of bac- more or less rapid' succession, by eria, made possible by thedecrease in the prostra- white cells of the blood tion, diarrhea, anorexia(lack- of appetite and injury to other; and dislike for food),and, fever. As ob- immune mechanisms ofthe .body; allows served after the nuclear an pverwhelmingrinfection to detonations in develop. :Japan,'the diarrheawas frequent and se- 7.38 rAmo'ng .othereffects observed in .vere in character, beingwatery at first Japan was a tenden'cy towardspontaneous and tending to become internal bleeding' bloody later; how- near the end of the first ever, this/may have been relatedto preex- week. At thesame time, swelliglig and in- isting,diseases Thus,Tor flammation of the throat was not uncom- .large dose (over1,000 rems) : survival mon. The development ofsevere radiation improbable - illness amorig the Japanese was accan-, 7.42 The panied by, an increase inthe body temper- sooner the foregoing symp- ature, which was probablydue to second- toms of radiation injurydevelop the ary infection. Generally therewas a step- sooner ill-death likely to result.Althoughr theremay be no pain during the first few like rise between .thefifth and seventh' 4 days, sometimes .dayi, patients experience.malaise, accom- as early as the third day panied by'marked depression following expoSure, andusually: continu- and fatigue. ing until the day ofdeath. At thetlower end of thddose range; the early stages of thesevere radiation illnes 7.39In addition to fever, themore serious cases exhibited severe are followed by a lprent period of2 or 3 emaciation and days (or .more), duringwhich the patient delirium, and death occurredwithin 2 to 8 appears to be free from sympto-ms, weeks. Examinationafter death revealed al- a decrease in size of and though iirofound changesare taking place degenerative in the body, es?ecialjyin the blood-form- changes in testes andovaries. Ulceration of the mucous,membrane ink tissues. This period,when it occurs, is of the large in- followed bY arecurrence of the early testine, which is generallyindicative of-symptoms, often accompanied doses of 1,000rems or more,, was also noted by delirium in some cases. or coma, terminating-in death usu:ally . -within a,few days to 2 weeks. 4 7.40 Those patientsin Japan whbsur- vived for 3 a 4 months,and did not sue- "cumb totuberculosis, lung disease,or EFFECTS OF RADIATIONON BLOOD other complications,gradually recovered. CONSTITUENTS, j There ivas no evidenceof permanent_loss 7.43 Among the --of hair, and examination.of 824 survivors biologicalconse; some 3 to 4 years later showed.that .quences of exposure of the whole bodyto a their single dose of.nuclearradiation, perhaps blood composition,Was not. significantly the most striking and different from that ofa cpntrol group in a characteristic are city !pit subjectelttgluclear the changes which takeplace in the blood attack. -and blOod-forming 7.41 Very large dOsee organs. Normally, these of whole-body ra- changes will occur only fordoses ireater. diation (apvfoximatély 5,000rems ar more) Wan 25 reins, Much result in. "pfompt information on the changes in the central hematological :response 6f human .nervolzs system_The symptoms beings are hyper- to nuclear radiationwas obtained after 105 t. 'or the nuclear, explosions in Ja.pan and also nurnber of n eutrophils to normal does riot from observations on victims of laboratory occur for stverlil months. accidents. The situation which developed 7.47In contrast to the behavior of the An the Marshall Islands hi March 1954, neutrophils, the number Of lymphocytes, 'however, provided the opportunity for a produced in partg of the lymphatic tissues vety thorougfi study of the effects of small of the body, e.g., lymph nodes and spleen, and moderately large doses 'of radiation shows a sharp drop soon after exposure to (up to 475 rems) on the blood of human radiation. The lymphocyte count continues beings. ,The descriptions given below, to remain considerably below normal for which are in general 'agreement with the several months and recovery may requike, results obseryed in Japan, are based many months or even years. However, to largely on this study. judge from the observations made in Ja- 7.44One of the most striking hemato- pan, the lymphocyte count of exposed indi- logical changes associated with radiation viduals 3 or 4 years after exposure was not injury is in the number of white blood appreciablY different from that of unek- cells. Among,these cells are the neutto- posed.persons. . - phils, formed chiefly in the bone marrow, 7.48 Asignificanth'ematological which are concerned with resisting bacte- change also occurs in the platelets, a con- rial invasion of the body. The number of stituent a the blood which plays an impor: neutrophils in the blood increases rapidly tant role in blood clotting. Unlike the' fluc-- during the course of certain Vypesof bacte- tuating total white count, the number of rial infection ,to cornbat the invading orga, platelets begins to,decreaSe soon after ex- nisms. Loss of ability to meet the bacterial posure and" falls steadily and reaches a invasion, whether due to radiation or any minimum at the end of aboutsa month. The other injury, is a very grave matter, and-decrease in the nurrber of plateiets is fol- bacteria which are normally held in check lowed by partial recovery,, but a normal by,the neutrophils can then multiply rap- count may not be attained for several idly, causing serious consequences. There 'months'or.even years after exposure. It is are several types of white blood cells with the decrease in the platelet count which different specialized functions, but which partly explains the appearance of hemor- have in common the general property of rhage and purpura in rafliation injury. resisling infection or remoVing toxic prod- 7,49 The red blood cell (erythrocyte) ucrs from.the body,or both. count-also undergoes a decrease as a re- 7A5 After the body has been exposed to sult of radiation exposure and henlor- radiation in th,e sub-lethal range, i:e., rhage,.so that symptoms of anemia, Cg., about 200 rems or less, the total number of pallor, become -apparent. However, the white blood cells may show a trarvitory change in the nuMber of erythrocytes is increase during the first 2 days or so, and much less striking than that which occurs then decrease below normal levels. Subse- in the white blood cells and platelets, espe- quently the white count may fluctuate and cially' for radiation doses in. the range of possibly rise above normal on occasions. 200 to 400 rems. Whereas the response in During the seventh or eighth weeki, the these, celis iA rapid, the red cell count white cell count becomes .stabilized at low shows little or no change for several days. levels and a minimum probably occurs at Subsequently, there is a decrease which about this time. An upward trend is ob- may continue for 2 oK 3 weeks, followed by servedAn succeeding weeks but complete a gradual increase in individuals who sur- recovery may require several monthsor viVe. 7.50 As an ,index of severity of radia- 1.46 The neutrophil count parallels the tion exposure, particularly in the suble- total white blood cell count, so that the thal range, the total white cell or neutro- initial increase observed in the latter is.phil counts are of limited usefulness be- apparently due toillIcreased mobilization cause of the wide fluctuations and the fact of neutrophils. Complete return of the that several weeks may elapie before the 1-06 14.1o maximum depression is obsered.The Hiroshima and Naghsaki lypmphocyte count is of at the time of more value in this burst. The major AtomicBomb Casualty respect, particularly in the lbwdose range, Commission studies relate shthe depressionoccurs within a few hourg to the survivors who were alive during theinitial survey, dr'of exposure. However,a marked decrease about five years after. theburst. There- in the number of lymphocytesis observed . .fore, the sample excludesthe more se- even with low doses and there isrelatively verely injured who died littlg difference with largedoses. prior to 1950. These exposed people havebeen studied, 7.51 The platelet count,on the other through both a biennial hand, apRears to exhibit physical examina- a regular pattern, tion and after death byan autopsy pro- with the maximum depressionbeing at- gram. 'Because, of different, latent periods tained at approximately thesame time for the effects of radiation various exposures in the .have developed sublethal range. with.the years since 1947. Forexample, in Furthermore, in this range, thedegree of the 1970's,.as leukemiadecreases, malig- depression from the normalvalue is nant neoplasms (tumors)are rising rap- roughly proportional tothe esti'mated idly, for those exposed inutero or in child- whole-body dose. It has beensuggested, hood. Some of the mostsignificant find- therefore, that the plateletcount might ings from various studiesare extracted serve as_a convenient and relativelysim- here in paragraphs 7.54-7.61from the 1973 ple direct method for: determin41gthe se- technical report of the Atomic verity of radiation injury in Bomb Cas- the sublethal ualty Commission's report"Radiation Ef- range. Thp main disadVantap is thatan fects on Atomic BombSurvivors." appreciable decrease in theplatelet count is not apparent untilsome time after the exposure. 'bENETICEFFECTS 7.54Significant effects of parentalex- LATE EFFE-CTS OF IONIZINGRADIATION posure' to the A-bomb on stillbirthor in- fant mortality rates, birthweight of child, 7.52 There area number of conse- or on the frequency of congenital malfor- quences of nuclear radiation whichmay mations haVe nOt been detected.The sex not appear forsome years after exposure. ratio (natio of male to female Among them, apart from babies) was genetic effects, expected to decrease if themother had, are the formation of cataracts,non-spe- been' irradiated, and to cific life shortening, leukemia, increase with pa- other forms ternal irrailiation. An earlierstudy sug- of malignant disease, and retardeddevel- gested such a shift, but opment of children in utero additional data at the-time of failed to confirm this hypothesis.No rela- the exposure. Informationconterning tionship has been observed these late effects has been obtaihed between ph- from rental exposure and themortality of chil- oontinued studies of varioustypes, includ-dren. No significant increasein leukemia ing those in Japan madechiefly under the incidence has been observed direction of 4.11e. Atomic Bonib in the off- Casu'Alty, spring of persons exposedto A-bomb radiation. A preliminary study 7.53 The Atomic Bomb. of the off- Casualty Coril- spring of A-bomb survivorsshowed no 'evi- rilissinn was established in 1947to provide dence of radiation effects surveys and studies ori the delayed effects on chromosomes. Recent studies show whitecorpuscle dam- of the A-bornbs. Over 400 reports hadbeen age after 20 years (see 7.61). issued by 197$. A nationwideenumeration 'was made tin Japan at the tinie of the 1950 national census to identify whowas in RADIATION INJURIES 7.55 Three major symptoinsof 'acute 'The Aryinic Bomb Casualty CM/IMMOof the U.S. National Acad. radiation exposure Wereobservedloss of emy of Sciences-National Research Council is sponsoredby the Atomic Energy Commission and administeredin cooperation with the Jima. hair, bleeding, and mouthlesions. Acute nese National Institut, of Retail. One of itspurposes is to study, the radiation symptoms increasedfrom 5% to iong.torm effects of exposure to nuclear radiation 10% among those exposedto total dose of 107 50 rem to 50% to 80% of those with about the death rate for all causes, especially 300 rem exposure, after which the propor-, among infants, increased with inten don leveled off. radiation exposure of the mother How- ever, no increase in mortality fro s J9Ice- DELAYED EFFECTS ON GROWTit AND mia and other cancers was obse No DEVELOPMENT relationship betweeh rheumatoid ..,,ritis and radiation dose has been found. neg- 7.56 'Head circumference and height ative finding does not .mean that certain were significantly smaller in children in effects will not occur later. Abnormalities utero whose mothers. were exposed cold pf the minute surface blood vessels were evidenced major radiationsymptoms. Con- found in those under 10 years ATB who. ( sistently smaller head and chest circum- were.exposed to 100 rem or more. Lip and , ferences, weight, standing and srfting tongue mucous membrances were more heights at ages 14 to 15 years were fbund frequentiy affected than were nail fold among Nagasaki children whose mothers and eyelids. These findings suggest that were exposed to high doses. Height, A-bomb exposure affected.the entire vas- weight and head circurnferences at 47 cular system. There was no evidence of .a years of age wEre significantly smaller in relationship between the prevalence of the Hirosh-inia in utero children whose' cardiovascular diseases and radiation ex- mothers were exposed. Decreased head posure, on between mOrtality from cardiov- . circumference was most prominent among ascular diseaSes and radiation. those in the first trimester of gestation at time of burst (ATB). Body size was smaller NEOPLASMS and body maturity advanced in the Hiro- shima exposed children. Adult height was 7.58 There were minor elevations in significantly less among Hiroshima chil- mortality from causes other than neo- dren 0-5 years of age ATB (at time of plasms (abnormal growth) but, all in all, burst) exposed to high doses. Dose effect there was little evidence of radiation ef- declined with increasing age ATB, but fect on other causes of death, including adult weight was less regardless of age taerculosis, stroke, and other diseases of ATB. Tissue samples from the exposed the circulatory system. Lung cancer mor- population suggest accelerated ageing tality increased with dose. This increase among those exposed. There was no radia- was particularly significant for those ex- 1, tion effect on bone growth among those posed at ages 35 years and over ATB. The exposed to ladiation in utero ATB. occucrence of thyroid cancer was higher in Women than in men and showed asignifi- DELAYED EFFECTS OF DISEASE cant elevation with the increase in dose. OCCURRENCE For those less than 20 years ATB, no sex difference for thyroid cancer was evident. 7.57 The first' demonstrated delayed ef- Salivary gland .tumors increased more fects of the A-bombs were radiation Cata- than five-fold among survivors exposed to racts in about 21/2% of survivors" within high radiation doses compared with the 1000 meters from ground zero ATB. Cata- nonirradiated population. the relative racts were the only delayed manifesta- risk of breast cancer was significantly tions of ocular injury from the A-bornb. higher among the- heavily =irradiated The latent period for subjective disturb- women. Women Who were xoung at the ances from cataracts appears to have been time of the bomb are now entering the about two years. Prevalence of mental re- ages of high risk froth breast cancer. No tardation was high in those exposed in relationship has been found to date be- utero less than 1500 meters from ground tween radiation dose and-prevalence of zero. Mental retardation was more fre- cancers of the stomach, gall bladder and quent in those exposed between the 6th bile duct, liver, bone, and skin. Mortality and 15th weeks of pregnancy, the period of from disease was higher among survivors hrain development. For in utero children, who received large radiation doses Than 1011' 112 among those with small dosesor those not disease increased with dose in'e cities. EXcessive mortality was among Hip- espe- shirna females and among those0-19 yeirs ciallçh* h for leukemia wherethe radiation "effe ATB in Nagasaki. An increase inpreva- appeared to be presenteven^ lence of miscellaneous eye diseases after among ,those estimated to have received radiation exposure wis noted,except 10-49 rem. Mortality fronicanoerapant among females age 50 or more ATB. from leukemia was also elevatedin survivors with large radiation'doses, but could OTHER FINDINGS " be __demonstrated withreliability only s. 'among those with doses exceeding200 7.61 No consistent differenceshave rem. been found by radiation expostke forpreg- nancy, birth and ,stylbirth rates, andzero LEUKEMIA pregnancies. Studies' of culturedlympho- cyte's (white corpuscles)have demon- 7.59Leukemia rates in the highdose strated that radiation inducedchromo- groups,. have declined persistently during some changes still persist more than 20 the period 1950 to 1970,but have not years after exposure. Furthermore, their reached the level experiencedby the gen- frequency appears to be proportionalto eral population. However, deathrates for the exposure dose. A highSproportionof cancer of other sites have increased those in utero whose mothers receiveda sharply in recentyears. The latent period dose of at least 100rem evidenced complex 'for radiatidn inducedcancers other than chromosomal abnormalitiesas compared leukemia appears to be 20years, or more. to the comparisongroups. There has been There was increasedleukemia with a dose- no manifestation of clinical disease associ- response relationship with the peakoccur- ated with chromosomal abnormalities. ringabout six years afterexposure. The effeies greatest.among those exposed EXTERNAL .HAZARD: BETA BURNS during childhood. The lowestdose cate- gory with a high frequency of leukemta 7.62Injury to the body from external was 20-49 1.em. This effect at 291-49rem sources of beta pIrticles can' arise in two was lqund in Hirirshtt whereneutrons general ways. If the beta-particleemit- constituted a substantial fraction-of the tell, e.g., fission products inthe fallout, total dose. In Nagasaki,-exposure to neu-- come into actual contact with the skinand trons was very small andno &saes of leu- remain for an appreciable time,a form of kemia occurred amongourvivorsexpbsed radiation damage, sometimesreferred to to 5-99 rem. as "beta burn," will result. In addition, in an area of extensive 'early fallout, the MALIGNANT NEOPLASMS whole surface of the bodywill be exposed to beta particles.coming frommany direc- 7.60 After a latent period ofabout IS.tions. It is true that clothingwill atten- years, children who received radiation mete this radiationto a considerable ex- doses of 100 remor more have begun to" tent; nevertheless, the whole bodycould *develop an excessive numberof malignant receive "'large dose "fromeça particles - neoplasms. Now,. 25years a ter exposure, whi9h might be significant. the accumulated increaseis nost striking, 7. with no evidence that Valuable information concerning a peak has been the development and healingof beta barns_ reacAed. Duringthenext 10 years, these has been obtained from observatipns persons will be entering ages when of cancer the Marshall Islanders whd were''Axposed incidence ordinarily begins toincrease. Forty cases of anezi:. to fallout in March .1954; Within:about5 confirined in hours of the, burst, radioactivematerial A-bomb survivors in Year period, but commenced to fall on the increase in risk due some of,the islands. to radiation expo- Although the falloutwas observed as a sure was not significant when comparedto white powder, consisting largely of the population. The prevalence parti- of thyroid cles of lime (calcium oxide) resultingfrom 109 the decomposition of coral (calcium car- bonate) by heat, the isalnd inhabitants did not realize its significance. Because the weather was hot and damp, the Mar- shaleseemained outdoors; their bodies were moist and.they wore relatively little clothing. As a result, appreciable aniounts of fission products fell upon their hair and skin and remained there for a considerable , time. Moreover, since the islanders, as a rule, did not wear shoes, their :bare feet we're continually subjected to contamination from fallout on the ground. 7.64During the first 24 to 44 hours, a number of individuals iu the more highly contaminated groups experienced itching FIGURE 7.55a.Beta burn on neck shortly after and a burning sensatipn of the skin. These exposure. symptoms were less marked among those who were less ,contamined with early fallout. Within a day to two all skin symptoms subsided and disappeared, but aftbr the lapse of about 2 to 3 weeks, epilation and skin- lesions were apparent off the areas of the body which had been contaim- inattd by fallout particlep. There was apparently .no erythema, either in the early stages (primary.) or later (secondary), as might have been expected, but this may have been obscured by the natural colora- tion of the.skin. 7.65--The first evidence of- skin damage .,was increased pigmentation, in the form of dark colored patches and raised areas (ma- FIGURE 7.65b.Beta burn on feet shortly-after cules, papules, and rasied plaques). These If exposure. lesions developed on the exposed parts Of

,the bqdy not protected by clothing, and occurred usually in the following order: caused ,by gamma rays, rather than by scalp Iwith epilation), neck, shoulders, beta particles, as the same effect has been depressions in the forearm, feet, )imbs, observedindark-skinnedpatients nd trunk. Epilation and lesions of the undergoing X-ray treatment in clinical scalp, neck, and foot were most frequently practice. observed (see Figures 7.65a and 7.65b). 7.67 Most of the lesions were superfi- 7.66In add,ition, a bluish-brown pig- cial without blistering. Microscopic exami- mentation of the fingernails was very com- nation at 3 to 6, weeks showed that the mon' amortg the Marshellbse and also damage was mogt marked in The outero among American Negroes. The phenome- layers of the skin (epidermis), whereas non appears to be a radiation. response damage' to.the deeper tissue was much less peculiar-to the dirk-skinned races, since it severe. This is consist6nt -with the shOrf was not apparent- in any of the white range of beta particles irf animal tissue: Americans who were exposed 'at the Same After formation or dry scab, the lesions, time. The nail pigmentation occurred in a healed rapidly leaVing h central depig- number of individuals who did 'not have'___mente.rrounded by an irregular skin lesiops. It is probable that this. was zone of ihcreased pigmentation. Normal

1410 eral cases about a year elapsed before the normal (darkish) skin colorationwas re- stored (see Figures 7.68a and 7.68b). 7.69 Regrowth of hair, of the usual color (in contrast to the skin pigmentation) and texture, began about 9 weeks after contamination and was 'complete in 6 months. By the same time, nail discolora- \ tion had groWn out in all but a few individuals. Seven years later, therewere only 10 cases which continued to show any effects of beta burns, and therewas no evidence of malignant changes. Blood studies of platelets and red blood cells indicated levels lower than average at 5years after exposure; at 7 years after exposure the platelets continued to be slightly de- FIGURE 7.68a.Beta burn on neck after healing. pressed. It thps 'appears that repair of bone marrow injury was not complete at this time. In the 1961 examination of the pigmentation gradually spread outwardin Marshallese people there was'a possible the course of a few weeks., indication of bone growth retardation in 7.68Individuals who had beenmore children 34414, Were babies at tile time of highly contaminated developeddeeper le- the explosion. sions, usually on the feetor neck, accompanied by mild burning, itchingend pain. These lesions were wet, weeping,and ul- INTERNAT. HAZARD cerated, becoming covered bya hard, -, 7.70 Wherever fallout occurs there isa scab; however, the majorityheeled r.eadily chance that radioactivematerial will en- with the regular treatmeintgenerally em:'ter the hody through the digestive'tract ployed for other skin lesionsnot connected (due to the consumption of food andwater ; with radiation. Abnormal pigmentation effects 'persisted for contaminated with fission products), some time, and in sev- through the lungs (by breathing aircon- taining, fallout particles),or .thropgh wounds or abrasions. It should be noted thgt even a very small quantityof radioactive material present in the bodycan pror duce considerable injury. Radiationexpo- sure of varidus organs and tissues from, internal' sources is continuoust subject only to depletion of the quantity of active platerial in the body as.a result of physical (radioactive decay) ar41 biological (elimination) processes, Ft.ithermore, Iiriternal sources of alPha emitters, e.g., plutonium, or of beta particles, or soft (low-energy) gamma-ray emitterd, can dissipate their entire energy withina small, Possibly sensitive, volume of body tissue; thus calving

considerable damage. 4/4 7.71' .The situation just des&ibed sometimes aggravated by the fact that- FIGURE 7.68b.Beta burn on feet after healing. grtain chemical elements tend toconcen- . 111 trate in specific cells aY tissues, some ofreason is that the nose can filter out al- which are highly sensitive to radiation. most all particles over 10 microns (0.001 The fate of a given radioactive element centimeter) in diameter, -and about 95 per- which has entered the -blood stream will cent of those exceeding 5 microns (0.0005 depend upon its chemical nature. Radioso- centimeter). Most of the particles descend- topes of in element which is a normal ing in the fallout during the critical period constituent of the body Fill follow the of highest activity, e.g., within 24 hourg of same metabolic processes as the naturally the explosion, will be considerably more occurring, inactive (stable) isotopes of the than 10 microns in diameter. Corise- same element. This is the case, for exam- quently, only a small proportion of the ,ple, with iodine which tends to concentrate early fallout particles present in the air in the thyroid gland. will succeed in reaching the lungs. Fur- 7.72 An element not usually found in thermore, the .optimum size for passage thg 'body, except perhaps in minute traces,'from the alveolar (air) space of the lungs will behave like onetwith similar chemical to the blood stream is as small as 1 to 2 - properties that is normally present. Thus, microns. The probability of entry into the 'among the absorbed fission products, circulating blood of fission products and strontium and barium, which are similar other weapon residues present in the early chemically to calcium, are lwgely depos- fallout, as a result of inhalation, is thus ited in the calcifying tissue of hone. The low. Any very small particles reaching the radioisotopes of the rare earth elements; alveolar spaces may be retained there or e.g., cerium, which constitute a considera- they may be removed either by physical ble proportion of the fission products, and means, e.g., by coughing, or by tbe lym- plutonium, which may be present to,some phatic system to, lymph nodes in the me- extent in the fallout, are also "bone-seek- diastinal (middle' chest) area, where they ers." Since they are not chemical ana- may accumulate. logues of calcium, however, they are de- 7.75 The extent of absorption of fission posited to a smaller extent and in other products and hther radioactive materials parts of the bone than are strontium and through the intestine is largely dependent barium. Bone-seekers, are, nevertheless, upon the solubility of the particieW;Wit potentially very hazardous because they early fallout, the fission produc4 as well can injure the sensitive bone marrow as uranium and plutonium are chiefly where many blood cells are produced. The present as oxides, many oxides of stron- damage to the blood-forming tissue thus tium and barium, however.aresolub1e, sa results in a' reduction in the number ofthat these elements enter, the blood blood cells and so affects the entire body stream more 'rekdily and find their way adveisely.) a into the bones.' The element iodine is also 7.73 The extent to which early fallout chiefly present in a soluble form and so it contamination can $.0..j-nto the blood soon enters-the blood And is concentrated stream will depend upon two main factors: in the thyroid gland. (1) the size of the particles, and (2) their 7.76In addition to the tendency of 'a solubility. in the body fluids. Whether thea particular element to be talten 'up by a material is subsequently deposited in specifib organ, the main consideration, in some specific tissue or not will be deter- determining the hazard from a given ra- mined by the chemical properties of the diOactive iSotope inside the body is the elements present, as indicated previously. total radiation dose de1iver4d/while it is in Elements Which do not tend to concen- the bodY (or specific organ). The most im- trate in a particular part of the body are portant factors in' determining this dose eliminated fairly rapidly by natural proc- are the mass and half-life of the radioiso- ,esses. tope, the nature and-energy of the radia- 7.74 The amdunt of yadi6active Mate- tions emitted, and the lengths of time it rial absorbed,frOm early\fallout by inhale- Ever/ander these conditions, only about tO percent of the strontium tiOn appears to be relatively small., The or barium is tiftually absorbed. y 7 - "-a- U 16 stays in the body. This time is dependent 133 and 135, would contribute .materially upon the "12iologkal half-time" which is to the total dose to the thyroid gland. . the time taken for the amount ofa partic- Howeyer, their radioactive half-livesare ular element in the body todecrease to measured in hours, andso they decay to half of its initial value. due to elimination insignificant levels within a few days of by natrual (biological)processes. Combina- their formation. It should. be Mentioned tion of the radioactive half life and biologi: that, apart from inimediate injury,any cal half-time gives rise to the effective radioactive materiarthat enters the body, half-life," defined as the time requiredfor even if it has a short effective .half-life, the amount of a specified radioactiveiso- -may c9ntribute to damage whigh doesnot tope in the body to fall to half ofits become apparent forsome time. original value.as a result of both radioa,c'- 7.79In addition to radioidine, the rilOst dye decay and natural elimination,in most cases of interest, the effective half-.important potentially hazardou's fission products, assuming sufficient amountsget life in the body asa whole is essentially int() the body, fall into two the same Us that in the principal tissue groups. The (or fibt, and more significant, containsstron- organ) in which the element tendsto con-, tium 89, strontium 90, cesium 13-7, and centrate. For some isotopes it is difficultto express the behavior in terms of a single barium 140, whereas the second consists of a- group of rare earth and relatedele- effective half-life becttise of theircompli- ments, particularlY cerium 114' and the cated metabolic mechanisms in thehuman body. chemically similar yttrium 91. 7.80Anothei;potentially hazardous ele- 7.77 The isotopes repr6sentingthe greatest potential internal hazard ment, which -may be present tosome eic- are telit.-is, the enly fallout,*is pintonium,in those with relatively short radioactive the form of the alpha-particle emitting half-lives and comparatiyely long biologi- isotope plutOnium 239. This isotope has cal half-times. A certainmass of an isotope a - long radioactive half-life (24,000 years)as of short radioactive half-life willemit par- tièles at a greater rate than'the well as a lctfig biological half-time (about s'ame 200 years). Consequently,once it is depos- mass of another isqope,possibly of the ited in the body; mainly same element, having longer half-life. on certain sur- Moreover the long biological half-time faces of the.bone, the amount of plutonium present ind its activity.decrease ata. very "Means that the active material willnot be slow rate. In spite of their shortIange in readily eliminated from the body by_natu- the body, *the:AcOntinued action of alpha ral processes. ,For exaMple., theelement particles 'over a period.of iodine hasa fairly long biologicalmaff-time - years can cause In many indiyiduals. significant injury. In sufficientamounts, Ihe actual 'value var- radlum, which isvery simijar to plutonium ies oNier a..i4e 7ange.- froma feivelays in in tehese reSpects, Hs-known to sdnie P.416ple'to maNtYears mothers, hue, cause necro- 'Os and tumors of the bone, andanemia on the ave4ge,iI-lis about 90 ilays.,Jodine--resulting.in death:. is q-uickly taken up by the thyrhidgland .from -w15,ictp, it is generally eliminated 7.81Expetimenta1 evidence indicates slowly. Zhe radioisotOpe iodine-13Ja.,-that nearlY all, if_:notall, inhaled Wilton- 'fairly common fissionproduct,.has a radio- limn deposits in the lungswhere,a Certain active halfIlife of only' 8 days. Conse-portion, less than 10 peirnt,relnains. quently, if a sufficient,. quantity of, Some of this is found in thtbronchial this'lyiph nodes.,For thi& isotope enters the blood stream it iscapa- reason, the primary ble of causing serious damage to the thy- hazard from inhaled, plutoniumis to the Pangs and bronchial lum'ph roid.glanbecause it reakains theredur- nodes. It is of ing essen ia ly,the wholeof itsradioactive interest to note that despitethe large life. amounts orradioactive material which may:pass through the kidneys in theproc- 7,78 At short times aftera detonation, ess of elimination, these organs ordinarily . other ra&isotopes of iodi`Ae,e.g., iodine "are not greatly affected, BYcontrast, ura- 117 113 fk

Iiium causes damage to the kidneys, but as ot either..the short effective half-lives of a chemical poison rather than because of the radioisotopes, the sparing solubility of its radioactiVity. the oxides, or the relatively'large size of 7.82Early fallout-Accompanying the -the fallout particles. nuclear air burstacaer-Npan was so insig- 7.86 The body burden' of radioactive nificarit that At was4r6rObierved. Conse- materialamong the more highly contami- quently, no,information was Available ,con- nated inhabitants of the:Marshall Islands cerning the potentialities, of,fission prod- was never very large and it decreased ucts and other weapon rktOes as inter- fairly rapidly in the course of 2 .or 3 nal sources of radiationollbwing the in- months. The activity of the strontium iso- cident in the Marshall Islands in March topes fell off somewhat More slowly than 1954, how'ever, data of great interest were tWat of the other radioisotopes-, because of obtained. Because they were not aware of the longer -radioactive half-lives and the significance of the fallout, many of the greater retention in the bone. Neverthe- inhabitants ate contaminated food and less, even strontium *could not be regarded drank contaminatedy.rater from open con- as a dangetous source of internal radia- tainers for periods up to 2 days. tion in the cases studied. At 6 months 7.83, Internal deposition of fission prod- after the explosion, the urine of most indi- ucts resulted mainly from ingestion rather'viduals contained only barely detectable than inhalatiOn for, in aadition to the rea- quantities of r;dioactive material. sons given abo

Medical Care Not Needed 150 200 300

Some Need Medical Care 250 350 500 Few if Any Deaths Mon Need Medical Care 450 .... 600 . SO% + Deaths . Uttlia or no p ctical consideration ; FIGURE 7.95'.Radiation Exposure Doses.

7.96 To illustrate use of the figure, other long-term effects. These effects are most people receiving no more than a total comparatively minor. In a war emergency, of 150 R during a time interval less dian a first minimize the number of deaths and week (1 hour, 1 day, 3 days, for instance) second, keep,. the number of people for are not expected to need medical care nor whom medical care is needed as small as to become ineffective in work perform- possible. When circumstances permit,. Rre- ance. Also, people receiving more than 500 ferreeconsideration should be given to R during one:month will need ,medical children and adults still capable of pro- care, and 50% .or more may die. ..creation. As conditions permit, emergency 7.97This "penalty figure" is. intended measures should, be terminated and nor- ) for use by ciyil preparedness officials dur- mal standards reinstituted. ing 'a war, emergency to provide them a I4 simple 'and straightforward basis for tak-, 1 REFERENCES .0 ing into account the radiological elements of the problem. For example, replenish- The Effects of Nuclear Weapons.-7-Glas- ment of :a. shelter's inadequate water s-dp- stone, Samuel, 1964. ply might be justified if a small crew could DCPA Attack Enyironment Manual. do sib, and if each member's total week's Radiation Effects on Atomic Bomb Sur- exposure could be kept to less than 150 R, vivors.Technical Report 6773, Atomic or the month's ekposure less than 200 R. Bomb 'Casualty Cominission, 1973. 7.98It is known that radiation in- Final Report-Inhalation of Radióiodine creases the chances of genetic damage and from Fallout: Hazards and Countermea- . Taken from DCPA Attack Environment Manual, Ch4tor 1, sures.ESA-TR-72-01-1)CPA Research Contract No. DAHC20-70-C-0381, 1972. fi

4111101,

... , . CHAPTER

EXPOSURE AND EXPOSURE RATECALCULATIONS

1,Jp toc this pointwe- have learned that the effects of radiatiOn 2. To determine theexposure that exposure are im- wohl e received in a certain time portant and Vire haveseen what the medi- peri d. cal consequence§ are for. exposures over 3. To determine different periods of. time.We need a means an "entry time.'1 for a of calculation that- will prescribed exposure anda prescribed assist us in meet- stay time. ing -guidelines establishedfor emergency 8.4If the radiation 411. workers. ,Tall order? Complatedmathe- exgosure rate from rhatici? Not at all. Atleast not at the end the fission prOducts,produeed bya single of. this Chapter becauseby then we will weep.= is known ata certain time in a have learned: given location, this knowledgemay be used to estimate theexposure rate at any HOW to determineexposure and ex- other time at the same location assuming posure rates that there has beenno externally pro- HOWto predict, futureexposure and duced change in the fallout(i.e.,,from addi- . exposure rates tional contaminationor by decontamina- tibn). In any such calculation, theconcept WHEN.can- someone leave-shelterand for how long of RADIOACTIVE DECAY ISVERY IM- PQRTANT. WHY prediction andmeasurement - are possible DECAY OF FISSION PRODUCTS INTRODUCTION 8.5 As we saw in Chapier 2, eitchra- 8.1In chapter 6we saw that fallout dioisotope has a 'characteristic desak arrives at particularlocations with re- scheme (half-life). Theserange from a few -spect to ground zero atvarious times after millionths of a second to millions ofyears. burst, dependingon such factors as dis- When a number of differentradioisotopes tance, meteorological Conditions, are presentin this case the fission prod- 8.2- It was also shownthat radioactive uctS of the bomb (fallout)noone half-life contamination from fallout cou,lddeny the _applies for'the composite. Forthee fission. useofconsiderable areas foran apprecia- prodAts, the sharet--lived radioisotopespre- ble period of time. Thus,even without tbt-"Torninate in the period Anmediatelyfollow- material destruction fromblast or thermal ing the burst. Since their lf-lives(decay radiation, many areas; facilitiesand equip- rates) are so short (rapidI, the radiation ment could not be usedor occupied for level falls off quickly afterthe detonation. some time without extreme danger. And as thesf short-livedradioisotopes expend themselves through 8.3In deciding what protectivemeas- decay, the ures should be taken, including longer half-liSe isOtopes forman increasing survey,:proportion of the fission prbducts andthe monitoring operations inan area contami- rate of decay of the fission prodUcts .nated with fallout,lt isnecessary: de- 1. To make creases. Because of this pattern of decay, some estimate of the perniis- the material depositedon the ground- at sible time of stay fora 'prescribed ex--increasing times 'after 'the burst will be posure, or less aiid lees radioactive. 121 117 8.6In calculating the radiation expo; TIME (+NV DECAY RADIATION WORM sure (or exposur:e rate) dUe to fallpiit from ffssion products, the gamma rays (because 1000 .of their long range and Pénetratin &. power) - are.of greater significance than the beta 44 particles, provided of course that the ra- 7 1110 :, 100 Rfiii dioactive material is not-actually in contact with the skin or inside'the body: 87 ,Even though-there arg, 'different' 49 1/100 10 R/hr proportions of gamma ray emitters among the radioisotope§ in fallout at different '343 1/1000 1 R/hr . periods of time, the fact quit there is a pattern of decay dogs permit the development throtigh estiniates-orcaleii4W14146,134;&' 8.8.-.The 7:140 rule of thumb for ratt\ of decay. levels of exposure and exposure rate at :.; certain times after a detonation ant-in --; fact, permits prediction of exposure and STANDARD DECAY exposure rate with a iair degpee...of acpu- -THE ExibSURTftfIRATE FORMULA racy. There dreyiliair-WaIrsTyr-comirig up with these estimates or calculations, some 8.10, The following forinula is used employing a rule ot thlimie some employ--calculating expo-sure rates: ing .mathematical formulae, and others R, .=R T" employing graphic, preientations (norno- L 8:T1In this eqttation: grams). R = rate at a specific time NOTE R, = rate orl tiour after detonation- No coniputatiot 91 ,expoure or expd- (H 1-.1) 9 sure rate should be made until they' T = time (hours) after detonation begin to decrease. You SHOULD. NOT ,CALCULATE EXPOSURE RATES.. n.1-- 1.2 (fallout decay exiionent) WHILE THEY ARE INCREASING. Further, calculation is no sulistitute 140TE for-accurate instrument readings. When n is equal to 1.2 the situation is referred to as standard decay. When n assumes other values nonstandaAl de 9s cay conditions pxist...... TH1"711rWt7t-E-OF-THUMB STANDARD DECAYAN -EXPOSbRE

8.8 After exposure rates ha begun toy, RATE PROBLEM decrease, you can get erou ea of fu-'' 8.12If the exposure rate at a givph ture rates by using the 7:10 rule. Simply location .one hour after detonation. was 30,;:' stated, this rule is that for every seyn- - R/hr, what would the rate be' at thisloca../.-1 0- ;fold increase in time alter detonation, rion 12 hairs after detonation? there is a-ten-fold- decrease in exposure rate. Figure 8.8 demonstrates thls oiule of thumb., SOLUTIOIA R, = 30 R/hr 8.9 irkerefgre, we seetha , through use R ? of this rule ofthumb, if a 50 R/hr radiation- T = 12 hoars exposure rate exists Wthree hours after n = 1.2 detonation, by the en'd of 21 11.214s it will have' decrea,sed to 5 R/hr, and by the end Substitute values in t.h,e.'abor fcw.rp#11f,t of 147.hours it will have decreased to 0.5 R/ R, =RT" hr.. 23434, =R(12)" 30 =41 (19.74)* (51-1.2 _ 151-1.2) 30 E = R = 1-5-7-7r- 1.52 R/hr 1.2 - 1 50 15-0.2) 'From Figure 8.14' (12)-" =19.73

E = 250 (0.725 -0.582)** E = (250) (0.143) STANDARD DECAYTHE EXPOSURE E = 36 R FORMULA **From Figure 8.14 5-0.2 =0.725 and15-0.2 =0.582 8.13 The following formula is used in calculating exposure. STANDARD DECAYEXPOSURE RATE E = . T21-n) n 1 NOMOGRAM 8.14 In this equation: 8.17If, of the factors (1) time after detonation; (2) exposure rate at H +1, and E exposure from time T1 to T, (3) exposure rate at:a particular time, we R, = exposure iate one hbur after know any two, then the other one can be detonation (H + 1) found by using a nomogram developed spe- T, = time of entry cifically for expoiure rate calculatibns. = time of exit (You will recoghize these factors ascom- n= 1.2 (fallout decay exponent) ing from the formula of paragraph 8.10, namely, R1=RTn). The .nomogram appears, 8.15 As an aid in using either formula as Figure 8.17 and is based upen the - presented above, Figure 8.14 gives the standard fallout decay exponent of 1.2. computed values of T'.2. and T-').2 for vari- 8.18 To u,se the exposure rate nomo- ous selected values of T. ° 'gram 4hown in Figure 8.17, connect any two known quantities with a straightedge and read the unknown quantity directly. STANDARD DECAYAN EXPOSURE PROBLEM 8.16 What exposure would a monitoring team receive in a radioactive contami- STANDARD DECAYAN EXPOSURE nated area if the team entered thearea 5 RATE NOMOGRAM PROBLEM h hours after a nuclear burst and stared for 8,19If the exposure rate in an area is a period of 10 hours? The exposure rate at 60 R/hrt H + 5, what will be the rate at H + 1 wa's 50 R/hr. H + 10? 8.20Solution: With 'a straightedge,connect 60 R/hr on the "Exposure Rate at SOLUTION H + T" column mith 5 hourson the "Time ,After Burst" column. The tate of 410 R/hr R, = 50 R/hr ta read on the "ExposureRate at H 4. 1" T, = 5 hours column. Next, connect, with the straight- T, -= 5 +10 =.15 hours 5dge, 10 hours on the "Time After Burse" n column with 410 Rihr on the l'Exposure: Rate at H + 1" column and read thean- Substitute values in the above formula: sw.er directly from the "Exposure Rate at R, H + T" column, E = -T21-9 4"3`, n 1 , ). 126n8wer: 26 R/hr, .. . T=TIME , T =TIME ^PI T TIME T 1.2 T-02 . T1.2 T-v.c. T1.2 T-0.2 IN HOURS IN HOURS IN -HOURS 48.0 io4.1 0.461 0.555 .0.1 0.0631r 1.586 1.9.0' 34.23 49.0 106.7 0.459 20.0 36.41 0.550 0.2 0:1450 1.381 50.0 109.3 0.457 0.544 -0.3 -0.2358 1.273 21.0 38.61 55.0 122.6 0.449 22.0 4+0.82 0,539 0.4 0.3330 1.202 6o.o 136:1 U.441 23.0 43.06 0.534 0.5 0.4352 1149 65.0 149.8 0.434 .24.0 45.31 0.530 0.6 0.5417 1.110 70.0 - 163.7 0.427 1.074 25.0 . 47.59 0.525 0.7 0.6518- 72.0 169.4 0.425: 26.0 49.89 0.521 ' 0.8 0.7651 1.046 75 .0 177.8 0.422 10.518 , 0.9 0.8812 1.021 27.0 . 52.20 ;36.0 192.2 0.417 1.9,J 1.0010. 1.000 28.0 54.52 0.514 85.0 206.7 0,412 0.510 1:5 1.627 0.922 29.0 ,56.87 90.0 211.1 0.407 2.0 2.300 0.871 ' 30.0 , 59.23 0.506 95.0 4 236.2 0.402 0.503 , 2.5 3.003 0.833 31.0 61.61 96.0 239.2 0.401 3.0 3.737 0.803 32.0 64.00 0.500 100.0 251.2 0.398 4.o 0.758 33.0 66.41 0.497 5.278 120.0 ', 312.6 0.384 5.0 6.899 0.725 34.0 .68.83 0.494 140.0 376.2 '0.°372 6.o 8.536 0.698 35.0 '71.27 0.491 144.0 389.1s0.376 0.678 36.0 73.72_ 0.483 , 7:0 10.33 160.0 442.5 0.362 0.486 '8.0 12.13 . 0.660 37.0 76.18 168.4(1 wk) 468.1 0.360 0.483 9.0 13.96 , .0.644 38.0 78.66 180.o 508.5 0.354 ,0.631 39.0 - 81.15 0.480 10.0 15.85 j 220.0 577.1. 0.347 0.619 '11.Q 17.77 40.0. 83.67. 0.478 250.0 754.3 0.332 ..12.0 19.73 0.668. 41.0 86.17' 0.476 300:0 938.7 v0.319 13.0 21.71 0.599 42.0 88.70 0.474 336.0 (2 wk ) 1075.0 0.313 14.0 23.74 0.590. 43.0 91.23 0.472 504.0 e3 wk 1745.0 0.288 15.0. 25.78 0.582 '44.0 93.79 0.470 '672.04 wk 2471.0 0.272 0,574 45.0 0.467 '27.86 96.35 720.0 1 mo. 2611.0 0.268 -

IT:0 29.96 , 0.567 46.0 98.93 05 1440.0 2 mo. 6166.0 0.234 ..1.8.0 32.09 0.560 47.0 101.5 0463 2160.03 Mb. 10031.0 0.216

FIGURE8.14,-V-2 and Vs-2 for selected 4 124 sci°°1Wow. Rate Exposur. ht.'1 at H+1 L at 11+t 3°"' ThRt) (R) i --t2 2000 ,--

4 1000 4- SOOi T 600 8 10

300 +20 200 1- -I-.30

too4 50 Time After Burst 60

SO 40- 2 - 100 3 4

411 204_ ' = .17) 8 74 10 -, -14.-300 - 20-2, 10 4- /-1 30-1 81- 40-1 7-600 1-, 2 . tit 6 ar- 60 -1 soo t 812 4- 3 moo 100-2/-4

2000 '716 20 3000 28 4,7-36 -.1-5000

FIGURE 8.17,-Exposure rate noinogram.

z STANDARD DECAY7ENTRY TIMESTAY 8.22 This nomogram is found in Figure TIMETOTAL EXPOSURE NOMOGRAM 8.22. ,. ) . 8.23 To use this norhogram, connect 8.21Just as if is possible to develop atwo known quarltities with a straightedge nomogram for -expasure. rates- and time andiocate The -point on the "EIR1"e6Tumn through the use of the exposure. rate for- where qe straightedge crosses it. Connect mula and standard fallout decay exponent this point with a third known quantity and of 1.2, so can we produce -anomogram for read the answer from the appropriate col- the exposure formula. umn. 125 121: 4 a Teta Tamurajapasers hts (1 km) (E)

20 40. Stay Tim (Ws) 404 SO 1 1201 2037 40 3001-- 400.r- uor SO bOO 1 100 .011-0 20007 3000 .07 S000. .037

.041 00 1000 .031

./32

FIGURE 8.22.Entry time-stay time-total-exposure nomogram. STANDARD DECAYAN ENTRY TIME sure rate of 100 Rthr at H + 1 will be made at H + 6. What will be the maximum mis- NOMOGRAM PROBLEM sion stay time, if the exposure is riot to. 8.24 The exposure rate in an area at exceed 20 R? H + 7 is 35 R/hr. The stay time is to be 5 8.27Solution: Connect 20 R in the "To- .hours and the minion exposure is set at 35 tal Exposure" column with 100 R/hr in the R. What is the earliest possible entry "Exposure late at H + 1" column and tim e? read 0.2 in tIvp "E/R,"column! Connect 0.2 8.25Solution: Find the exposure rate in the "t/R," column with 6 hours in the at H + 1 from the ,Exposure Rate, Nomo- "Entry Time" column, and read the an- gram (Figure8.1'?):. Connect this value on swer directly froin the "Stay Time"col- the 'Expogure Rate at 11,+ 1" column with umn. 35 R on the "Total E)R9sure':. column and Answer: 2.1 hours. read 0.1 on the "E/R,"" clumn. Connect 0.1 on the "E/R," column with5 hours on "Stay Time" Column and read the answer STANDARD DECAYAN EXPOSURE from the "Entry Time" column. NOMOGRAM PROBLEM AnfiVieff H '24. 8.28 Find the total exposure for an individual who must work in an area in STANDAAD DECAYA STAY TIME which the exposure rate was 300 R/hi at NOMOGRAM PROBLEM H + 1. Entry will be made at H + 11 and 8.26Entry into an area with an expo- the length of stay will be 4 hours.

122 , 8.29Solution: Connect H +11 on the expoiure rate callulations. 'How about the "Entry Time" column with 4hours on the "Stay Time" 'column and read RADF Officr Have we taken care of 0.19 from him yet? You'll find that answer below, the "EIR," column. Connect 0.19in the "E/ R," column with 300 R/hron the "Expo- sure Rate at H +1" column and read the AN OPEN LETTER TO. RADEF OFFItERS answer from the "Total Exposure" col- We have arrived at the point where you will have to bear down hard. This umn. js the point at which yoint.own profes- Answer: 60 R. sionar-type RADtF knowledge makes , its depant" from, the, standard kADEF know-how'that willbe shared WHAT METHOD SHOULD MONITORS by so many members.ofyour RADEF USE? - organization. The following paragraphs are not 8.30 Nomograms, basedon theoretical impossible but then neither are they fallout radiaton -decay charact ristics, easy. If you miss a point, go back and. should be used by monitorsw en it is reread it because the basic material is necessary for them to make y6ugh esti- really here. You will probably notice, mates of future exposure rat here and there, .some repetition over s and expo- the preceding paragraphs but it is sures that might be expected in perform- intdnded asan aid to better under- ing necessary tasks outside theshelter. standing. However, when fallout from severalnu- We wilj begin with * * * ll clear weapons, detonatedmore than 24 hours apart is deposited inan area, the A REVIEW OF RADIOACTIVEDECAY decay rate may differ markedly fromthe 8.32 Each radioactive isotope assumed decay rate. For thisreason, cal- has a-- culations using nomograms should be,,lim- characteristic half-life. Theserange from a ited as follows: few millionths "of a Secondto millions of a. years. However,'-wkeri'many radioisotopes The time of detonation must be contribUte to the knoWn with a reasonable degree of exposure rate, as in the case of the fission products froma nuclear accuracyplus or minusone hour for weapon, no one half-life aPplies for the forecasts made within the first twelve composite. With fission products hours, and plusNor minus '2-3 hours there is_a for later forecdsts. predominance of siroxt-lived radioisotopes in the period imlnediatelyfollowing the b. If nuclear detonationsoccur more burst; hence the exposurerate decreases than 24 hours apart, predicted rates very rapidly. As these short-lived radioiso- may be considcrably in.errot. In this topes expend themselves, thelonger half- case, use the H hour of the latest life isotopes become dominantand the de- detonation to compute "Time After cay rate of the fission products decreases. Burst". 8.33 We know that radioactivedecay of c. At the time of calculation, eXposure the fission productscan be estimated us- rates must have been decreasing for ing the general equation R,= RP where R, at least 2-3 hours, and forecasts equals the exposure'rateat unit time, R should be made for periods no farther equals the exposure rate atany time T in the future than the length of time measured from the time of burst,and n is the radiation levels have been ob- the fiallout decay exponent.Time may be served to decrease. measured in any units7-minutes;hours, 8.31Have we covered the subject of 'days, weeks, etc.; provided unit tiineand T exPbsure and- expgsiireiate calculatiOns?-are expressed in the same units. That question prompts another question. What level of the RADEF organization STANDARD MECAYA WORD ABOUT are we talking about? Monitors? In that THE EXPPNENT (1.2) r case, yes, we have covered exposure and 8.34, Attempts to fit observed decay of 127 1 i3 't.

41-, fallout from actual' tests with a general ports or simply from observations of the equation of tthe form RI=RTn" have re-flash, the hlast wave,..or the cloud of the quired Values oFn ranging from about 0.9 detonation, the time of burst of most to 2.2. We.have learned that attempts to weapons within a radius of 100 to 200 predict the decay of actual fallout fields on miles will be' known. Thiis, the RADEF -e,the basis of any given decay law (i.e., Officer will know the time of formation of assuming some constant value for n) are most of the fission products in his immedi- almost certain to be grossly inacettiate. ate area and from the current "DF" report The value of n will vary with bomb design, he will generally know which specific deto- the amount ant type of neutron-induced n4tion is causing the major fallout prob- jactivity, fractiona nd in a particular lem in his community. area, with weatheringnd decontamina- 8.40 The RADEF OffiCer can then plot tion. or direct th plotting of observed exposure 8.35 .For planning purposes, a value of rates agai st time on log-log paper., Fu- n = 1.2 is frequently used and, fog. plan- ture fat s can be estimated by projecting ning, this value is quite satisfactory. How- the cur e to. future times of concern. ever, accurate ibtformation of exposure 8.41 However, as a practical limit, fore- rates and rates of decay must depend on casts of future exposure rates generally repeated mOnitoring under the same condi- shakld be made for periods no farther in tions at the same locations. the future than the length of time exposure rates have been' observed tp decrease. PLOTTING THE EXPOSURE RATEHISTORY 8.42 For example, if exposure rate pb- servations- have been decreasink for the 8.30Since the fallout at any location preceding 12 hours, they will be plotted may eonsist of radioactive material from and,.provided the plot for the last few sev,eral, different weapon's detonated at hours approximates a straight line, the materially different times, it will be im- curve can be extritolated (extended) for practical. to 'keep track of the individual 12 additional hours to forecast the rates contributions and ages of each set of fis- during that time period. Caution must be sion products comprising the fallout. The exercised in extrapolating the curve dur- most practical method of forecasting expo- ing periods of fluctuation, sure rates under these conditions appears to be based upon-the technique of plotting 8,43If, after aperiod during which the observed rates 4:Tersus time after detoba- logarithmic decay is approximately a ' tion on log-log paper and extrapolating the straight line, the rate is observed to mate- plotted curve. rially increasethis indicates the arrival 8.37 Plo4 of this tyPe for two or three of significant additional fallout. If the ex- representatjve points across a community posure rite appears to he equal to or less will generally be adequate. If the' require- than the maximum exposure rate from ment exceeds this, it may be advantageous erlier fallout, continue the original plot to compute the value of the fallout decay based on the "H hour" of the original exponent n and use the general equation fallout. Rib!=RT11 to predict future exposure rates 8.44However, if considerable time has in areas where the fission product compo- elapsed since arrival of the first fallout, sition is ehe same. and the increase in exposure rate equals S.38R1=RxTx" and R1=RJ)," etc. The or exceeds the maximum exposure rate niost -useful form of the general equation from earlier fallout, plot a new graph us- will _probably be R,T,P=RET. Application ing the estimated H hour of the latest of this formula is discaued in a later fa ll out arth e refereime-time. paragraph (8.55). 8.45After the plot indicates an orderly 8.39 The procedure for plotting ob- decrease Snearly a ,straight line log-log served exposure rates is as follows. From plot), extrapolation of the curve can again NUDET (report ot time of detonation) re- provide a reasonable basis for estimating 124 1 1)8AV, - exposure rates for futureperiods subject 1. First, we plot the data - to the-above-mentioned restriction. as indicated by the arrows inFigure 8.50a. ' 8.46It should be emphasized thatthe 2. Next, we draw actual exposure 'rate a smooth, curve - may vary consider- . through the plotted points ably fx-Rm the forecastrate. Thus, 'opera- as shown.' tions likely to iequire high in 'Figure 8.50h. radiaton expo- 3. lfow, in order to forecast sures arould' be carried outon the basis of the expo: obcerved rates, not forecastrates. The sure rate at H + 80 a'nd H90,0ve forecast is simply- extend the curve to 90hours as a a guide -to aid a local dotted line. This is cbordinator in planning hisforthcoming shown in Figure surviV"al andrecovery operations. 8.50c. 8.47 A forecast 4. Assume thatwe now receive addi-, exposure rate could be tional monitored data considerably in-Nerror if additionalfallout as follows: Tame after Exposure rate' Teme atter occurred after the forecastwas- made or if burst (hours) Exposure rate (RIhrCI.burst (hours) (R/hr) the rate of decay,,changed 70 materially from 155 100 103 .80 that indicated by the plotson the log-log 131 110' 91 90 graph. 115 120 83 8.48 The latest fallout analysis, based 5. We plot the additionaldata. upon current exposure ratereports, 6.' Then we draw should be the basis forcurrent operations. a smooth cUrve Plans for future operationsshould be through these additional pointsas based t.ipon Ple currentfallout analysis) shown in Figure 8.50d. Noticethe modified according to Jheforecast from a comparison between -the forecastex- Iog-log plot: posure rates and the actual up-dated plot. , 8.51 The fallout decayexponent n may A PRACTICAL EXAMPLE be computed directlyfrom the plotted exposure rate curve since n ,is numerically 8.49 The following exercisepresents a equal to the slope of thecurve. Further, n hypothetical situation. in whichwe will is constant only whenthe plotted line is predict future exposure ratesfrom a series straight. We can determine fifrom the of radiological reports. (Thecurve which graph by dividing the will be Used does notnecessarily measured distance represent AY in inches by the measureddistance AX a fallout decay cut-ve which might beex- in inches as indicated in pected in an actual situation.) Figure 8.50e. 8.50 We are given certaindata as for 8.52 Looking at Figure 8.50e, let's de- terming n at H + 110. Wesee that AY and AX are the vertical and horizontal dis- tandes, respectively, covered by thecurve Time after Exposure rate Time after burst (Hours) Exposure rate in the area ofour interest. we measure (R/hr) burst (Hours) (R thr) IF 0 these distances in inches, divide AYlky_AX, 18 - ,380 2 0 20 390 and.find that n at H + 110 is equalto 1.1. 3 1 22 410 4 23 24 415 8.53 Now, if practicai, 5 n !Can be used to . 250 26 410 6 forecast exposure ratesas indicated in the 790 28 495 7- following eximple. (A table of 910 30 400 logarithms 8 and a brief explanation 860 36 325 'of their use is 9 .... 805 42 280 included ai Figures 8.53a and8.53b.) 10 . 750 48 240 12 640 54 210 8.54 14 BefOre workingout 6ur example, 549 60 185 go back and reread paragraph '8.38. 16 460 You will find it helpful in solvingthe example. "8.55 Nowfor the sample problem in 125 . exp-osure rate forecasting using a .com- 4 days iS 108 R/hr; if n = 1.1, predict Puted vbzlue of n. The exposure rate at the rate at.1.1 + 8 days.,

R,, = 108 R/hr_,RxTyn. = Rytn' .,T,, =. 4 days. ,(10,8) (4). " :=.(1t,) (8)" = ? log 108 t 1.1 log 4=lg Ry + 1.1 log 8 8 dars, (2.0334) + 1.1 (.6021) = log R.), + 1.1 (.9031) n = 1.1 log R; = 2.0334 + 0.6623 0.9934 = 1.7023 eir Answer: Ry = 50.k/hr.

EXPOSURE CALCULATION FROM AN 8.61First, divide the expovre period into small increments. When the slope of EXPOSURE RATE .HISTORY CURVE tte curve is changing rapidly, the incre- 8.56 DCPA recommended radiological nitnts should be small. When the slope is defense reporting procedures proyide for relatively straight over the exposure pe- accumulated exposure reports each day riod, the increments may be larger. The from fallout monitoring stations for the increments need not be equal in size. first -six days following an- attack. These reports will be based on dosimeter meas- 8.62 As a general rule, an increment urements, which are the sir/Vest Means of should noi exceed ode.' half of the time determining exposures. Dosimeter* inte- from detonation to thlbeginning of the grate the exposure over a period of time increment. For exampl 'if the increments and account- direcWy for the decrease in begins at H 4- 10, il eh uld not be larger exposure rates due to decay. than 5 hours. Howe:ver,if the slope of fhe 8.57 However, there may be insiances surve chahgeS appreciably during this when the RADEF Officer must estimate time, it may be neces'sary to use even exposure from a series of exposure rate smaller increments. Duiing the initial pe- ...measurements. The following paragraphs riods of fallout deposition, the increments will provide a quick and easy method of should be no larger than 1 hour. estimating such exposures. 8.58It is relatively, simple to forecast 8.63 Now rook at Figure 8.63 to see how exposure rates and, consequently, total eX- a sample exposure period is.broken into posure of individuals when the fallout incrementS. decay exponent remains constant over long periods of time. These estimates, how- 8.64Next, w&determine the average ever, are normally made only after fallout exposure rate within each incrementand is Complete. multiply this by the elapsed dine. This will 8.59If we are concerned with estimat- give us the exposure for each increment ing the total exposure for the periods (1)- of and the sum of these exposures will give fallout deposition, (2) when the value of us the total exposurefior the period. The the fallout decay exponent is changing calculations involved are presente,1 below. rapi:d,ly,.. or (3) when fallout from, several detonations contributes to the exposure

rate, calculation of these estimates be- A v e r a g e exposure comes more coMplex. A v e r a g e title x 8.60 A satisfactory estimate of total ex- Increment exposure rate elapsed thrte.exposure - A ,4...... (100+80)-2=90 __, qax 2=18a . _ ,posure can be .obtained by plotting expo- B (80+50).,-2=65 5xa=195 sure rates versus time after detonation C (50+30)-,2=40 40x 5-4200 I and determining total exposures from the graph. - Total 575 12' ,130 126 - I I I .1 _I II II II I, II I I I I ...... 733:...... :1:3::::=Nrolleillzammtra...... 1/11=4111MINVIIMINI00111)011.01110.000 ...:: 041014 M 0 MOMIIMMI IMMO, Mal IBM MMIIIIII MI...... "00000 IMMIIIMIIIIIIMIMMIMIIMMUMIS ..... IMS1111111.1111101/ 111111111IIMI MITI, AM VW V: VI IVININVIIIVIV4 WU .... VIM 111::: aVIMMIN OOOO *MI lino asset NOV OM 10 141_041 . 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FIGURE 8.50e S. 4 ; 5 6 7 8 9 .e'Pl. 0 1 2 '3 4 '$ 6 ,7 '8 , 9 . .' 0 , 1 3

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VIGURE 8,53a.-Common Lorifht,ps.

4 - Yi loamy $ '

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This disdassion of,logarithms will deal only less than the number of digits to ttid left

with the_so-called "common" logarithms whieh of its decimal point . . . use a base equal to 10. A or First, a definition of a logarithm::

4 - if the number 11 is less,than 1, the the lbgarithm of a number N to the characteristic of its logarithm is neg7 base a is the'expoilent x or the power if.the first digit which is not-

to which the base,must be raised to . zero is found in'the,kth decimal plAce,

equal the nuMber N. , the characteristic is -k.

In other wordst Now, to use logarithms-to multiply two numbers, M and N, find log M and-log N: log N is the logarithm of N to the base 10 if N = 10x, then x = log DT'

Thus: if M = 10Y, then y = log M

if N = 10x, then x = log N To multiply M times N:

FUrther: x + y = log ME+ log N = loge(MA.

'log N = characteristic + mantissa When x (the logarithm of N) is added to y (the logarithm of M), the sum is another logarithm, (For instance, log 12.3 = 1 + .(5864 = 1.086h) the logarithm of M times N. The antilogarithm of this value of x plus y is M times N. Orr The mantissa (or delmal piri Oithe logarithn) is found from the tables of logarithms (Figure antilog (x + y) = antilog (log M + log h) I. 8.53a). = Mtimes N,4, The chaNt'eristic is determined in accordance with two rules: Antilogs are found by using the tables in reverse, i.e., enter the.tablei with a log (not if the nuMber kris greater than 1, the a number) in-Order to find a number (not a characteristic of its'logarithm is one ,log). .4116 -MN

FIGURE 8.53b,--1Jsing Common Logarithms. mmlomme..m. NB=IM ftula ..... =UM SSA. InO I nmsrossocansault MssiX1111114I1111111111 NEM tttt urn / 11 ==EiBEIBEEEE:Fiaii=a1E:HiE:::::.

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RADIOLOGICALMONITORING TECHNIQUESAND OPEIATIONS Consider, for just a moment, what .kind MONITORING TECHNIOUES of radiological defense couldwe build if we 1 did not have 'radiologicalmonitoring? It i9.3The following paragraphsdescribe wouldn't be worth much, wouldit? Radiol- tlie detailed techniquesand procedures for ogical defense is builton facts and radiol- conducting each type of radioiogicalmoni7 ogical monitoring provides thosefacts for toring activity. Falloutstation monitors RADEF decisions and actions.Once a )are responsible for performing all ofthe nuclear attac.k is past, thisbecomes even Monitoring techniques outlinedin this sec- more true with each passing hour for just tion. Shelter monitorsare responsible for as long a time as radiation remains,a performing all of the techniques,except danger., So if there isa technique in this for unsheltered exposurerate measure- business of midiologicalmonitoring (and ments and unshelteredexposure measure- there is, very definitely), let'stake a look ments. at it to find out: BOW to Monitor SHELTER AREA MONITORING WHEN to monitOr =9.4 Epns,) tre-ratea-shouki-be-measured WHATto moniror inside of a shelter,or a fallout monitoring WHO to monitor station to determine the bestshielded portions of the shelter and its WHERE to"nionitor immediate adjoining areas. Procedures for tilismonitor- . ing are as follows: (... as to WHY lo monitor, we have 1. Use-the CD V-715. learned all the reasons forthat one quite a 2. Check the operabilityof the instru- few pages back!) me,nt. 3. Hold the instrumentat belt height (8 INTRODUCTION feet above the ground). 93 The data supplied byradiological 4-. take readings ,at selected'locations monitors is the key to RADEFdecisions throughout the shelter and adjoining .ori what to. do and howto do it. And in-time areas and record these on_a sketch of ofoemergency thesedecisions may be the the area. key to living or dying.Let's, take a closer look af this vital activity. UNSHELTERED EXPOSURE RATE MEASUREMENTS WHATIS RADIOLOGICAL MONITORING'? 9.6Fallout monitoring stationsreport 9.2Radiological monitoring,is defined unsheltered exposure rate readings.Pro- as the detection andmeasurement of ra- cedures for observing unshelteredexposure ratesare as follows: diation emitted by fallout.With the ipfor-. mation gained throughmonitoring we can: 1. Use the CD V-715. (1) determine extent andlocation of fallout; (2) validate predictionsabout fallout; Paragraphs 93 through 9 30 and (3) decide on are based upon the HANDBOOKFOR a course of action. RADIOLOGICAL MONITORS, FG-E-5.9. 135' 2. Check the operability of the instru- standard operating procedure. NOTE: ment. It is anticipated that radiation reports from the county levelOk govern- 3. Take San exposure rate reading at a ment upwards would be limited to: ipecific location in the fallout monitoring station. This should be done as a. A flash report immediately upon soon as the exp6sure rate reaches or measurement of .5 R/hr and in- exceeds 0.05 R/hr. creasing. b. A severe radiation report when the 4. Go outside immediately to a pre- radiation level reaches 50 R/hr and ---:----plannedfiocation in a-clear, flat area increasing. (preferably unpaved), at least 25 feet c. The highest or radiation peaklevel s. away from bUildings,and take an outside reading. The outside reading if above 50 R/hr. should be taken within three minutes d. The time when the decaying expo- of the reading in step 3 above. sure rate passesdownward and below 50 R/hr. 5. Calculate the outside/inside ratio of e. The timewhefi the radiation level the fallout monitoring station, by di- decays to .5 R/hr. viding the outside exposure rate by 9. Take all exposure ratemeasurements the inside exposure rate. The protec- outside after the unsheltered expo- tion may vary from location to loca- 25IUhr. tion within the station. The outside/ sure rate has decreased to inside ratio referred to here is ap,pro- 9.6 The CD V-717 remote reading in- priate only for the location where the strument may be used for taking outside inede exposure rate measurement is exposure rate.Measurements. The CD V- observed. 717 is used as described below: Position thP instrunionf at a selected 6. MUltiply future inside exposure-Tare location within the fallout monitoring readings by the oftitside/in*I3e ratio at station. the selected location to o tain the 2. Place Ole removable ionization cham- Outside exposure rate. For exaMple: ber 3 feet above the ground in a rea- If the inside reading is 0,5 R/hr and sonably flat area and at least 20 feet the outside reading is 80 R/hr, the from the fallout station. Preferably ratio can be found by dividing the this should be done prior tokallout outside reading by the-insidereadin'e. arrival. Ie is desirable to cover the Thus, 8a$ 0.5 = an outside/inside ra- ionization chamber with a light plas- tio of 160. If a later inside reading at the same location in the fallout moni- tic bag or other lightweight material. toring station is 4 R/hr, thus outside 3. Observe outside exposure rates di- exposure rate can be calculatedby rectly. multiplying the ratio by the inside 4. Record and report exposure rates in 4 reading. Thus, 160 x 4 = 640 R/hr. accordance With the ---:partitular, RADEF organizationitandard opera-- 7. Recalculate the outside/inside ratio at leagt onde every 24 hours during the ting procedure. first few days postattack, unlesilhe outii4exposure rate is estimated to UNSHELTERED EXPOSARE be above 100 R/hr, This isnecessacy MEASUREMENTS because the _energy of gamma radiation is changing, thus changing the 9..7Fallout monitoring stations report outside/inside ratio of the falloutunsheltered exposure readings. Proce- monitoring station. dures for taking these readings are listed below: 8. Record and report the exposure rate 4 measurement in accordance wjth the 1, Zero a Cti V-742. particular RADEF . organization 2. Measure the unsheltered exposure 136 140 'f. kate in accordancewith paragraph RADIATION. EXPOSURE fl EGO fID 000 Teti Essspgt 9.5. of Def ts ExpaftreD EstcgoW Dots Roos .70.04 DOE 3: Selectan insiile 1o:cation' where the Aatn, , 27 N Moe iti-Ake, expoSure rate is "'RAW%r etg11.4 A1.2.04 '11-- approximately one- Sec Sot Ilk 4-9.7 --2fo -3-5-15- tenth to one-twentiethof the unshel- S tered exposure Dottfg TirolErufs rate and positiortlhe Extmtfito Daly CD V-742 at this Doto , location. G A.,11,2 1 5- /r . 4 /7/42 5" Ze' 4. Determinetheoutside/inside fatio for itloir 9 2. s- 9 S this location inaccordance with the r.: y-tota se procedure explainedpreviously. 5. Read,the CD V-742daily. If the daily exposIfte at this locationcould exceed .200 R, estimate thetime required for 'a 150 R _ exposure on the CD V-742. 000 CORM Record this reading,rezero the do- DATE simeter, and repositionit. To deter- FDONTSIOE RACK SiDE mine the daily unshelteredexposure, multiply the daily exposure at this FIGURE 9.8.Radiationexposure record. !location by the outside/insideratio: 6. Record thereadings andrezero the which read more than half scale.If instrument. some shelters are divided intocom- partments or rooms thatmay have different outside/inside ratios, theex- PERSONNEL EXPOSUREMEASUREMENTS posure should be measured- or calculated for each comMtment. 9.8 The monitormust determine the daily exposure of allshelterees or fallout 4. Instruct the shelteroccupants to re- -monitoring statiönoccupants. Procedures cord-th-eir-individualexposures on for determining dailyexposures are as their radiationexposure record (Fig- follows: u're 9.8), as approved .bythe shelter 1. Zero all availableCD V-742's. manager. Exposure entries should be made to the nearestroentgen. Con- ,2. Position thetosimetersso that repre- tinue to read the dosimeters sentative shelter each exposures will be day. Record the accumulatedexpo- measured by the instruments.-The sure, if ineasurable. monitor must exerciSe judgment in 9.9If monitors or otherpersons are positi3Oning these instruments.The, required to go 'outside, these additional outside/inside ratiomay vary consid- exposures should be measuredtandre- erably at different locationswithin corded. the shelter. 'The instrumentsshould be-placed within theareas of greatest occupancy, which may change with PERSONNEL MONITORING time. During the earlyhigh radiation 9.10 The present DCPAconcept is that period, occupaney wiltbe coneen- any amount of contamination, remaining trated'in the highprotection areas of the shelter. Later, the on clothing -after brushing--and-&akingas occupancy of a countermeasure would be insignificant the shelter can beexpanded"-If repre- as a health hazard. sentative readingsare to be obtained, the dosimeters mustfollow the loca- , thin shifts of the occupants. FOOD AND WATERMONITORING 3. If several dosimetersare positioned 9.11 in one compartment, Eood 'and water mdnitOringcrite- read the dosime- ria and techniquesare being reevaluated, ters each day andaverage the total and are subject to e36hosures. Recharge change. During an early dosimeters fallout condition, theradiation level is 137 141 Ti

likely to be above the range of the CD,V- 1. Know the specific actomplishment, 700. and, in effect, render it unaidtable for extent, and impo'rtance of each moni- determining whether food and water sup- toring mission. plies are acceptable for human consump- 2. Know the..4116wable exposure for each tion. mission and the expected exposure Q.12Since radiation passing through rates to be encountered. food does_not contaminate it, the only dan- 3. Make allowances for the exposure to -"- ger Wo did be the actual swallowing of fal- bereceived traveling to and.frtom the lout particles that hapPen to be on or hi monitoring area. Obtain information thefiiod itself (or on the can or package about the condition of roads, bridges, containing the food). Fallout particles etc., that might interfere .with the ihonld be wiped or washed off. Reaping mission and _lengthen exposure time. threshing, canning and other processing 9.17Next, consider the clothing which would prevent dangerous quantities of fal- will be needed for the mission. - lout from getting into most procetsed 1. Tie pants cuffs over boots or leggings. foods. It is believed that ordinary precautions, normally taken in preparing foods to 2. When dusty conditions prevail, wear a protective mask, gloves, head cover- g eat, would keep radiological contamination within accelitable limitations. ing, and sufficient clothing to cover skin areas. If no masks,are available, 9.13Water systems might be affected cover the nose and mouth with a by radioactive fallout, but the risk would be sniall. Water stored in covered con- handkerchief. tainers,- or in covered wells would not be 9.18 Very important, of course, is the contaminated after an attack. Even in un- equipment needed for the mission. covered-containers, indoors, such as buck- 1. Use the CD V-715. the exposure ets Or bathtubs filled with emergency sup- rates are expected to be below 50 mR/ plies of water, it is highly unlikely that the hra1wearry-th-e-CD-V109. wittei would be contaminated by fallout 2. Wear a*CD V-742. particles. Practically all of the fallout par- 3. Carry contamination signs, if areas ticles that drop into open reservoirs, lakes, are to be marked. This may also re- and streams.would settle to the bottom. quire stakes, heavy cord, hammer and 9.14 Do note discard food and water nails for posting the signs. known, or, suspected to be contaminated. 4. Carry a pencil, paper, and a map with It should be placed in storage and used monitoringpoints marked. When other less contaminated food is not 3.19 The procedures for area monitor- longer. available. If only contaminated ing are as follows: food sir water is available use supplies with 1. Zero the dosimeter before leaving the smalleit amount of contamination the shelter and place it in a pocket to protect it from possible contamination. AREA (MOBILE) MONITORING 2. Check the operability of the CD V- 9.15 Area monitoring is used to.locate 715 and CD V-700, if it 'is to be used. zones of contamination and determine the/ 3. Use vehicles such as autos-, trucks, exposure rates within these zones. The, bicycles, or motorcycles whdn dis- monitor should be informed by his Radiol- tances are too great to cover quickly ogical Defense Officer concerning routes on foot. Keep auto and truck cab win- to be followed, locations where readings dows and vents closed when traveling ,are needed, the mission exposure,"and the under extremely dusty conditionS. estimated time needed to accomplish the The use of a bicycle or motorcycle mission. may be more practical if roadways 9.16First, plan to keep personnel expo- are blocked. sures as low as possible: 4. Take readings at about three feet

1311 1 2 1- r

(belt high) above the ground. If read- 5. Divide sixty minutes by thenumber , ings are taken from a moving vehi-` of minutes the dosimeterwas ex- cle, the- instrumept shouldbe posi-. tioned on the seat beside the Posed. Multiply this number bythe driver. ineasilred exposure. Example: If the If readingi are to betaken outside p. exposure is 10 R for a measured inter: vehicle, the monitor shouldmove val of five minutes, therate can be severatfeet away from the vehicleto take the reading. calculated as follows: . (60 5) x lb = 12 X 10 =120 Rihr. 5. 'Record -the w'rettposurerate, the time anI Iocatim for eachreading. ,If MONITORING ,OPERMIONS,,- readings are 'taken withina vehicle, - this should be noted in thereport. 921 Radiological monitors,whether as- 6. Post markers, if requiredby the mis- signed to community sheltersor fallout sion. The-marker ,shouldface away monitoring stations, performessentially from the restrictedarea. Write the similar operations. Anydepartures from date, time, andexposure rate on the the operations described herewill be the back of the marker. result of decisions by State and localorga- 7. Read the pocket dosimeter nizations and mukt be reflectedin their at fre-standard operating procedure's. If local quent: intervals42_ determinewhen or return to shelter- should, begin. State standard operatingprocedures are , 'Al- not in exiitence, monitors should lowances shouldbe made forthe ex- follow posure to be received during return,the procedures outlined inthe following to the shelter. paragraphs. 8. Remove outer clothing on return to°READINESS the shelter and visuallycheck all OPERATIONS personnel for contamination. 9.22 During peacetime,wall assigned W.-Decontaminate, if required. monitors should: 10. Report results of thesurvey. 1. Participate in refreshertraining exercises and tests as scheduled -11. Record radiation eiiposure(see Fig- to ure 9:8). maintain an organized monitoringca- pability. EXPOSURE RATE READINGSFROM 2. Prepare a sketch of themonitoring DOSIMETERS statiOn or shelter and adjoiningareas for use during shelter 9.20 Survey instruments occupancy. should always 3: Plan a location in the be used to measureexposure rates. How- shelter in coor- ever, if no operable survey instruments dination with the sheltermanager to are available, dosimeters serve as the center of monitoringop- can be used to erations. calculate exposure rates byfollowing the Ateps listed below. 4. Make all' operationalsets available 1. Zero a CD V-742. once-every two-years to the-4Mb 2. Place the zeioed dosimeter maintenance shop for repolibration, at a se- iepairs ifnecessary, and new batter- lected location. ;pc 3. Expose the dosimeterfor a measured interval of time, but donot remain in SHELTER OPERATIONS the radiation field while the dosime- 9.23Upofi attack orarning of attack, ter is being eXposed. This intervala shelter monitor 6 rts to the shelter should be sufficient to-:allowthe do- manager in his assigned shelter and iimeter to readat leasi 10 R. It per- may forms the following CHECK LISTof oper- take one or two trialsbefore the ations in order: proper interval can be selected. 4. Read the dosimeter. 1. Perform an operationalcheck on all survey meters. 139 113 2. Charge dosimeters. a...The inside exposure rate _reaches or exCeeds la 4/hr at any time 3,, Position dosimeters. at- predesigt mated locations in the she/ter. during thp shelter period. 4. Report to the shelter manager on b. The calculated exposure will ex- the conditions of the instruments 'ceed 75 R. within any two days pe- and the pOsitioning of dosimeters. riod-of shelter. 5heck to see the doors, windows, or 13. Issue each shelter occupant a Radi- other openings are closed during fal- tion Exposure Record. As approved" lout deposition. by the shelter manager, advise each 6. Begin outside monitoring to deter- person once daily Of their exposure mine the time of fallout arrival. Ad- during the previous 24 hours..Follow vise the shelter manager when the procedures in paragraph 9.8 to calcu- rate begins to increase. late exposure of shelter occupants. 9.24During the latter part of the shel- '7. Insure that all persons who haveter period, when there is a less frequent performed outside missions in con- need for in-shelter monitoring, some of the taminated areas, follow the protec- shelter wonctors may be required to pro- tive actions indicated: vide monitoring services in support of 8. Food and water stored in the shelterother emergency operations. A monitoring Should be acceptable for consump-capability should always be retained in tion. Leav,e contaminated items out- the shelter until the end of the shelter side the shelter or place them in period, isolated storage near the shelter. 9.25 At the conclusion of the shelter 9. Take readings at selected locations period, all shelter monitors, except those throughout the shelter and record regularly assigned to emergency-services, the exposure rates on prepared may expect reassignment. sketches of-thearea. Particular attention shotild be given to monitoring any occupied areas close to fil- FALLOUT MONITORING STATION ters in the ventilating system. Show OPERATIONS the tinT of readings on all sketches. 9.26 For his own protection and the 10. Furnish all sketches to the shelter protectiowscif all members of a fallout mon- manager and recommend one of the itoring stAtion, the monitor should per- following courses of action: form' the same shelter operations as de- a. If exposurerates are not uniform, scribed in paragraph 9.23. In addition, the occupy the areas with lowes't ex- fallout station monitor will measure, re- posure rates. - cord, and report unsheltered Ocposure and b. If 'space prohibits locating all exposure rates to the appropriate EOC. shelterees in the better protected Unless otherwise specified by the local areas, rotate personnelz. to distrib- standard operating procedure, the monitor ute exposure evenly. DO not ro- will: tate personnel unless thire is a 1. Make a FLASH REPORT when the . significant difference in file expo- outside exposure rate reaches or -ex- sure between the best and the ceeds 0.5 R/hr. leatt protected shelter occupants. 2. Record and report exposure and expo- 11. Repeat the above procedure at least sure rates in accordance with local once daily. If there is a rapid change repOrting requirements. in the exposure rate; repeat at least once every six hours. MONITORING IN SUPPORT OF 12. Inform the shelter manager teno- EMERGENCY OPERATIONS tify the appropriate emergency oper- 9.27 As soon as radiation tevels de- ating center and request guidance if: crease sufficiently to permit high priority

1,40 114 operations and later, as operationalrecov- 9.29 When a service is directed toper- ery activities including deeontamination. forom a mission, the emergency operating of vital areas and structures are begun,all center furnishes the follovring informa- , fallout station monitors andmost commu- tion: nity shelter monitors are requiredto provide radiological monitoringsupport to 1. The time when the servicemay leave these ,qpertiQns..RadJQlog1cal Defense Of- shelter to perform its mission, ficers will direetr the systematicmonitor- 2. The illilowable exPoStrie for thecom- ing of areas, routes, equipment andfacili- plete mission; that is, from time of ties to determine the /extent ofcontamina- departure until return to shelter. tjon. This information will Helpthe Civil 3.. The exposure rate to be expected in Preparedness organization determine the area of the mission. when people may, leave shelter,what areas may be occupied, what routesmay be used, and whatareas itnd facilities 9.30 The monitor supportingemer- must be decontaminated. gency operations Will: 9.28 Many government services persOn- 1. Read his instruments frequently dur- nel, such as fire, police, health,and wel- inf each operation and advise the in-- , fare personnel, willserve as shelter moni: dividual in charge of the missionon tors or fallout station monitors during ihe necessary radiological protective shelter period. However,as operational re- measures and when the crew must covery activities are begun, they will have leave the area and return to shelter primary responsibility in theirown fields, to aioid eAceeding the planned mis- . sion exposure. with seeondary responsibilities inradiol- , ogicat defense. Most serviceswill provide 2.. Determine the effectiveness of decon- for a radiological-monitoringeapability for tamination -ineasures,if-auppdrtin the protection of their operationalcrews decontamination operations. performing emergenZy activities.The .ca- 3. Monitor equipment on return to shel- pability is provided until the Radiological ter, or base of operations, to deter- Defense Officer determines thatit,is not mine if it is contaminated, and ifso, required. Services provide this capability- direct decontamination of that equip- from their own ranks, to th4,eextent practi- ment. cal, supported by shelter monitorsand fal- 4.Advise the crew on persminel decon- lout station monitors, when requiretd. tamination if necessa0.

141

; CHAPTER 10

PROTECTION FROM RADIATION _

ALPHMPARTICLES TILAV* ONLY Different forms of protection fromnu- e MOUT AN INCH IN AIR AND AXE STOPPED SY A SHEET OF clear radiation are available tous. Some of PAPER OR THE SKIN TISSUE these alv all right, some are excellent and sO'me are poor.

We need information on these forms of SETA.PAIDCLES TRAVEL A FEW FEET IN MR AND ARE STOPIID SY AN INCH Of protection and thia. chapter will eveus WCr00 OR A THIN SHEET OF ALUMINUM that information. We will see: : HOW time can provide protection GAMMA-RAYS TRAVEL NUN. , HOW ,DREDS OF FEETIN distailce can provide protec- AIR AND ARE REDUCED tion SY THICK LEAD OR CONCRETE HOWshielding can provide protec- °WIVE tion oh, v P WHAT makes a shelter 1?-S 4.9.09 t-----WHAT-else-is--necessary FIGURE 10.2,-Three kinds of nuclear radiation. (3) the unfissioned material of the bomb itself. The unfis'sioned material is oner- INTRODUCTION, allyelpha emitting, while the'fission prod- 10.1 As we haye seen in previous,chap- ucts and the neutron-induced radioactive ters, the residual nuclear radiation from isotopes are beta-gamma emitters. See fallAt presentsa number of difficult and Figure 10.2 to refresh your memory about involved problems. This is iq not only be- the penetrating power of the.3 major kinds cause the, radiatiOns are invisible, and re- of radiation. quire special instruments -for their detec-. tion and measurement, but also becalise of ,the widespread -and long lasting character PROTECTIONFROM of the fallout,- In the event ofa surface -EXTERNAL RADIATION burst of a high yield nuclear weapon, the 10.3 To protect against external radia- area 'contaminated by the fallout could 1/e' tion, (basically gainma rays), there are expected to extend well beyond that in three tfiings you can put between you and which casualties result from blast, ther- the fallout causing the radiation: TIME, -mai radiation, and the initial nuclearra- DISTANCE, AND A SHIELD. Protection diation. Further, whereas the other effects is'provided by: (1)1controlling the length of of a nuclear explosion are over ina few time of exposure; (2) controlling the dis- seconds, the residual radiation persists for tance between the body and the source of a considerable time. radiation; and (3) placing an absorbing 10,2In Chapter 6 we learned that ra- material between the body and the source dioactive material .released by a nuclear of radiation. 4 explosion consists of: (1) radioactive parti- 10.4It is not generally possible to use cles created by the fissioning of the bomb only one factor of. protection. The factor-of material, (2) particles made radioactive by time is always involved, that is, time is neutrons released at the time of explosion, usually used in combination with distance, 142

_ 54

shielding, or both. Forcomparison, con- clear weapons in order to permit radiation sider the problem of protecting the eyes'levels to decrease,. It should beremem-.. from ultravioletrays when taking a sun- bered, however, that it is possible for bath. Ultraviolet ra- rays may be harmful to diation levels to inerease after longpe- the eyed. A certain amountcan be toler- riods of.decreasing ated, but beyond this point exposure rates, be- dainage may_cause of the deposition of additional fal- - be eaused. Theeyes can be protected in lout. three ways. First is toregulate.the time ebt "tinder the sunlamp. Second. is to DISTANCE regulate the distance maintainedbetween the eyes 'and the sunlamp.Third is to 10.7 The effect of distance froma fal- shield the eyes with sunglasses.The den- lout field is iomettmesmisunderstood. ser the glasses, the more ultravioletrays When the distances are large in relationto are filtered out and thereforean individ- the size of the radioactivesource,. the ex- ual can be closer to thelamp and stay posure rates decrease by the square of the there a longer period of timewithout hurt- distance from thesource. This ,!`inverse ing his 4,7es. In order,tounderstand each square law" can be an effective protective of the three factors ofprotection, it is measure when using the sealedsources necessary to discuss them separately. (sometimes called point sources) ina DCPA Traiatig Source Set. However, ina fallout field, which consists of billionsof TIME "point sources" spreadover large areas, 10.5For simplicity, letus disregard the the inverse squa're law is ofno value to a decay of the radioactive materialsin fal- RADEF Officer in computingthe decrease lout and assume thatwe are in an area in exposure rates with distancefrom con- where the exposure rate remainsconstant taminated areas. at 25 R/hr. In one hour,we would be 10.8 the fact thatexposure rates do exposed to 25 roentgens ofradiation.If we decrease with distance froma fallout field stayed 2 holm's, we would be exposedto 50 will be very important tous, however, R. If we stayed 4 hours,our exposure when we discuss the protectivefeatures of would be 100 R, and for an 8 hourstay we large buildings later 'in thischapter. Dis- would receive anexposure of 200 R. Thus, tance is also important to the RADEF time-could he u-Seil as a protectivemeasure Officer when,he considers theuse of decon-: by keeping the period ofexposure down to thmination as a radiological countermeas- an absolute minimum. For instance, if ure. An area called a buffer 'zone is us- work must be done ina high radiation ually decontaminated arounda vital facil- area, the work should be carefully planned ity to increase the distance of thefallout to minimize the stay time in thecon- field from the facility. The function ofthe ma area. buffer, zone is to reduce thegamma expo- 10.6 As iscussed in Chapter8, the sure rate which originates in thesur- cay of radioactive materials willcause the rounding unreclaimedarea. radiatio levels from fallout to,decrease with time. In the early periodetterdeto- SHIELDING nation, the decrease in, exposure rates is 10.9 You will.recall that thedamaging very rapid. At later times, the decrease is effects of gamma rays not as rapid because the longer lived comes from the fact fis- that the rays strike electrons inthe body -sion products make the majoricontribution and knock them out ot their to the exposure rate. Knowledge of orbit, and if the this happens to sufficientelectrons in the general decay pattern of radioactive fal- body, radiation injury lout suggests an additional occurs. If vie wish to w,ay in which stop a high proportion of therays before time is important. All work incontami- they get to us, we nated areas should be postponed can place between our- as long selves and thesource of theradiation a as practicable after the detonation ofnu- material which hasa lot of electrons in its 43 147 0 1 makeup. The more electrons there are in the makeupof the material the more radiation will.be stopped. 10.10 Figure 10.10 shows lead and water in a kough comparison of their atomic makeup. Sinee lbadi has a lot more electrons in the orbits of each atothan does Water, lead makes a bqffer shield than. water. 10.11Figure 10.11 shows the relative efficiencY of various shielding materials. These materials are efficient in about the WATER 'proportions shoWn cm the chart In stop- FIGURE 10-10,--Comparison between lead atom and . ping the same amouIt t of gamma. Various shielding materials a uSed in various water molecule. applications, depending ip n the purpose ual. This is termed "barrier shielding." to be seed. Lead, for instance, is quite The second method is to increase the dis- compact and is most suitable where space tance of the individual from the fallout requirements are a factor, On the other field contributing to the individual's expo. hand, Water is used where it is necessary 'sure. This is termed "geometry shielding." to see through the shielding material and 10.13In most analyses it is necessary to work through it with a long-handled to consider the effects of both barrier and tool to perform necessary operations, such geometry shielding. This is termed "com- as, in processes in atomic plants where bined shielding." sawing or cutting the radioactive mate- 10.14 The heavier the barrier between rials is necessary: fallout and the individual, the greater the 10.12 When considering fallout shel- barrier shielding- effect. Examples of bar- ters, protection is generally achieved in riers in structures are walls, floors, and two ways: One metho.d is to place a barrier ceilings. between the fallout field and the individ- 10.15 Geometry shielding is determined by the extent of the fallout field affecting ILEAD anindividual, and/or his distance from it. Consiaer an example of geometry shielding. STEEL 10.16If two buildings are of the same height and similar construction, but of different area, the protection from ground contamination would be greater on the 1:!1111. 4ella tONCRETE 1,L2t:A. _ first floor in the building with the .larger area. On the/ other hand, if two buildings are of equal area and similar construction, EARTH but differ in height, protection from ground contamination would be greater on the upper floor of the higher building. WATER

THE SHELTERPROTECTION FACTOR - 10.17 - The effects of geometry shielding WOOD and barrier shielding are combined into a term very useful for considering the effec- FIGURE 10.11,Relatiye efficiency ofvariouL tiveness of various types of shelters. This shielding materials'. combined term is TI-IE PROTECTION 144 ft 4 8 4.

FACTOR: One definition is:a calculation of the relative reduction in theamount of radiation that would be received bya person in a protected location, compared to the_amount he would receive -if-hewere unprotected in the saX44oca ion. (See Glossary for the diffeince bet out- - side/inside ratio and protection faCtor.) .10.18If a shelter has a protection factor of 100, an unprotectedperson at the same ocation would be exposed to 100 times'i ore radiation thansomeone inside the shelter.-, , 41: 10.19 Where conditionsare favorable, ded protectioncan be had for little extra cost: 1,Vhfie licensed public shelters havea mimmum of PF 40, a higher degreeof protetion up to say 1,000 is advantageous. Thisill fxequently be possible in building

protec Ion into new structures.ae . 10.20',_ Thereare two ways to go about settingup adequate shelters: COMMU- NITY ACTION and FAMILY VICTION.It shoifk be stressed that they aenot mu- tually exclusive. In fact, they supplement each ther in a verynecessary way. Most peopl spend the largest part of theirtime at onear their homes and there are stro g sociological advantages to keeping FIGURE 10.22,-Grouy shelte'ring ina largebuilding. fanii y grouPs together ina time of crisis and, ardship. However, formany people it is n t practical to truct home shelters. 2. There would bemore opportunity to And, even if one psesses-the finest shel- find first aid and' otheremergency, ter n the world,j it will do no.good if he is skills ina group, and the risk of radia- cau ht away from home at a time of dan- tion exppsure afteran attack could be ger us fallout. more 'widely shared. Commynity shelters wouldprovide PU LIC SHELTERS shelter for persdns away from their Jairg-nes at the time ofan attack. 11.21Further, experience in Europe in 4. Group Slielters couldserve as a focus .W. rld War II and other human experi- for integrated communityrecovery en es under disaster conditions hp.ve activities in a postattack period. po nted to distinct advantages of the pub- 5. Group shelters couldserve other corn- lic shelter when compared-with the family munity purposes, as well,as offer pro- sh lter. There are severalreasons why tection from fallout followingan at- g up shelters are preferable in many cir- tack. c mstances: 10.22These are thereasons why the A larger than family-sizegroup prob- Federal _Gov,ernment has been involved_ ably would be better prephred to face with a number of activitiesinvolving a nucleaT attack than a singll -gUltdance,technicalassistance, and particularly if some members should moheyto encourage the developmentof be away from home at the time of public shelters. The overallprogram, attack. ° at, which got underway with the National 4 145 She lterurvey, aims at securing shelteirs shield their occupants adequately from, in exist'ng and new structures, marking the radiation given off by fallout particles. them, anmaking them availEible to the Usually, householders can make theseim- public, in_,an emergency, Where there are'provments thems ves, with imoderate ef- riot enough public shelters to accommo- fort and at low co t. Millions of/homes date all citizens, efforts are being made to have been suzvey for the Defense Civil pr,ovide more. ,In some cas6s, such ds Preparedhess Agency (DCPA) by the U. S. large cities, it may net be possible to build Census Bureau, and these householderS individual family fallotit shelters. Group have received inforthation .on how much ihelters Auch as illustrated in Figuh;10.22 fallout protection their basements would may be required to provide adequate pro- provide, and how to improve tr:iis .protec- tection in such situations. / ,tion. . , Shielding Material Is Required FAMILY SHELTERS 10.26In setting up any home fallout *A Home Sheltfr Mag Save Your Life shelter, the basic aim is to plaCenough 10.23Even though public fallout Lhel- "shielding material" betwe e ople in ters usually offer many advantages over the sheltei and the .fallout particles out- ome shelters, in many lacesespecially side. :suburban and rura there are few 10.27Shielding material is any sub- public shelters. If theresisone near you, a stance that would absorb and deflect the home fallout shelter may s ye your life. invisible rays given off by fallout particles 10.24 The basemena osome homes-outsye the house, and thus reduce the are usable as famili fal ut shelters as arhotilit of radiation reachirT the- -occti- they now stand, without any alterations or pants of the shelter. The thicker or denser changesespecially if the house has twothe shielding material is, the mkre it or more stories, and its basement is below would protect the shelter occupants. ground level. 10.28 Some radiation protection is pro- 10.25 However, most honje basements vided by the existing; standard walls and' vAuld need some imprdvements in order to ceiling of-a basement. But 4f they are thick or dense enoukh, other shielding material will have tojip added.

10.29Concrete, bricks? eartt and sand are some of the, materials that are dense or heavy enough to provide fallout protec-, tion. For comparative purposes, 4 inches of concrete would provide the same shielding density as: 5 to 6 inches of bAcks. 6" inches of sand or gravel. (May be packed into bags, cartons, -boxes, or other containers for easier.-- handling.) ' I 7 fnches of earth. - 8 inches of hollow concrete blocks (6 inches if filled with sand). 10 incs of water. 14 incIks of books or magazin.... 18. inches of wood. FIGURE 10.24.Home basement. How to PreRare a Home Shelter 10.30If there is no public fallmit shel- - 'Paragraphs 10.23 through 10.57 ar from the DCPA. publication"In Tim.of-Emergency," H-14, March 10.58. ter near plur home, or if you would prefer to use a famfiy-type shelter in a time ofofit or interfering with itsnormal p attack, you shouldprepare a home fallout OW use. shelter. Here is how to do it: 10.34 10.31 A PERMANENT However, if 12 inchesor mo e of 'BASEMENT the basement wall is aboveground I vel, SHELTER. If ybur homebasement--.-or one corner of itis below ground level, this plan should not be usedunless u add the "optional walls"shown in the your best and easiest action 'would beto sketch. prepare a permanent-type family shelter there. The required shielding 10.35Overhead protection is obtained material by screwing plywood sheets would cost perhaps $1004200,and if you securely, to have basic carperitry the joists, and then fillingthe spaces be- or masonry skills you tween the joists, with probably could do the work.yourself in a bricks or concrete short time. blocks. extra beam and a screwjack column may be needed tosupport the ex- .10.32Here,ere three methods of provid- tra weight. ing a permanent familyshelter in the "best" corner ofyour home basement 10.36Building this shelter requires that is, the corner which ismost below some basic woodviorking skills and about ground level. $1504200 for materials. Itcan be set up while the house is beingbuilt, or after- ceiling Modification Plan A ward. 10.33 If-nearly all your basementis Altd-nate Ceiling ModificationPlan B_ below ground level,you can use this pran 10.37This is similar to Plan Aexcept to build a fallout shelterarea in one cor- that new extra joists ner of it, without changing the are fitted into part of appearance the base.ment ceiling tosupport theadded

, r )14, `11

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f4,111V.I. lik"4*111111_11___, .x;-0..41,..itli --ft.tto;;;----

FIGURE 101151ermenent basementshelter.

147 bricks or blocks \,..,..\M:-,=z=Mt.I.....ii.li :11,7 =-1;11J-1111LAIMV-AllitIPAar0111 ...,""...... 011%1 ZaTa zi -az ,u 4---.Jaw:6w Aw - -;OVI0001 "111 screwjack157;111Mmosuiminmrs#000011 /gill column ler,OIMMOMMOMMMI10111101,MI '11 I l: il,,mmmemlurtif$mismommimmu ...0;;Ipriraillipoi concrete biotic or brick *,Ialw llsmomawasolin. --II II 11111IS,,7:441.1.1....MMOIrgiElir beam IIIINI:I.,411Willian61111:11 411111 OM AI11111W111111:P/IPW11111 rl WIT Mill OFINIVIila$9.01141 11001"reet--!... 111111' 4ZdiNV-111.11

optional walls screwjack column

FIGURE 10.33,--Cei1ing modification Wan A. 4 ,$ NEW ik 1 t .-- 41--rimiasvv JOISTS 1t ':-, -rordolLoie, '-- -,..:oftliffiNrArrAMPT49000011! -ilikliek-alUSWAINIAWAIIr 4 1 NIUMNIalramsimEmommorAw.V_, INIENtillailaraiWrIltarlaq0010=IIIIIIMMEMMINIMIWONNIIIINUOAilli oglew gi moommomearmstow=."-11 II!?i =Ma MIEMMINglitiMMISII. &Wig 111 MI ME MEN= NM MI II ,147:40 0" "Mall Mai MM. IM =MIN NM4 ' ,,,,k..a.". Nilill MIMEssamwins,=:77777---; Mila 1.1. MiPmillmillga_ i P EXISTING momeammmi 1,,,,,,A ,:i, ', 0, JOISTS swomommilotiitivinu, ., MliffillEll Luumm. fil 111111111f1 'Nita .

half basement ceiling width

half basement ceiling length

FIGURE%7,A1ternate ceiling modification Plan B. weight of the s 'elding (insteag of using a 10.39After plywood panels are screwed beam and a so ewjack column). securely' to the joikts, bricks or concrete 10.38 The new wooden joists are cut to blocks are then packed tightly into the length and notched at the ends, thenin- spaces between ..the joists.The bricks or stalled between the existing joists. blocks, as well as the joikts themselves, 148 152 will reduce the amount of fallout radiation at a cost of $150 in most partsof the penetrating downward into thebasement. country. 10.40 Approximately one-quarter of the 10,43 Made of concreteblocks 0? bricks, total basement ceiling shouldbe 'rein- the shelter should be locatedin the corner forced with extra joists andshielding ma- of your basement that terial. is most below ground level. Itcan be built low, to-serve 10.41Important: This plan (like Plan as a "sitdown" shelter;or by making it A) should not be used if 12inches or more higher you can havea shelter in which of your basement wall isabove ground people can stand erect. level, unless you add the "optionalwalls" 10.44 The shelter ceiling, however, inside your basement thatare shown in the Plan A sketch. should not be higher than theoutside groudd level of the liasementcorner where Permanent Concrete Block iv?. BrickShel- the shelter is luated. ter Plan C 10.45 The higheryour basement is 10.42This shelter will provide excellent above ground level, the thicker protection, and can be constructed you should easily make the walls and roof of thisshelter,

Place entrancewayon side or e'ral not facing'- x"posed Gesement wall

Increase thlbkness of shelter wall ii facing expoSed basement wailbY four Inches

Fy6RE1.0.42,Permanent concretelock or brick shelter plan C. 53 149 FIGURE 10.49.--Preplannedsnack bar shelter plan D. tv since your- regular basement wallswill would be to arrange to assemble a"pre- provide only limited shielding against out- planned" home shelter. This simply means shield- side radiation. gathering together, in advance, the ing material you would need to make your 10.46. Natural ventilation isprovided to 6.37 the air basement (or one part of it) resistant by the shelter entrance, and fallout radiation. This -Material couldbe vents shown in ihe shelter'wall. stored in or around" your home,ready for 10.47 This shelter can "be used as a use whenever youdecided to set up your storage room or for other useful purposes basement shelter. Here are twokinds of in non-emefgency periods. preplanned basement shelters. A Preplannecl Basement Shelter Preplanned Snack Bar Shelter Plan D 10.48If your home has a basement but you do not wish to set up apermanent- 10.49 This is a snack bar built of bricks type basement shelter, the nextbest thing or concrete blocks, setin mortar, in the

FIGURE 10.51.Preplanned tilt-up storage unit planE 1-4 1.50 "best" COrner of your basement (the cor- 10.55 The fallout ptotection offered' by ner that is most below ground level), It your home basement also can be increased can be converted qUickly into a fallout by adding shielding material to the out- shelter by lowering a strong, hinged "false side, exposed portion of your basement ceiling" so that it rests on tile snack bar. walls, and by covering yotir basement win- , 10.50 When the false ceilingis lowered dows with shielding material. into place in a time of emergency, the 10.56 You can cover the aboveground hollow sections of it can be filled with portion of the basement walls with earth, bricks or concrete blocks. These can be sand, bricks, concrete blocks, stones from stored conveniently nearby, or can be used your patio, or other material. as room dividers or recreation room furni- 10.57 You also can use any- of these ture (see bench in Figure 10.49). substances to block basement windows Preplanned Tilt-Up Storage Unit Plan E and tbus prevent outside fallout radiation 10.51 A tilt-up storage unitin the best from entering your basement in that man- corner of your basementis another ner. method of setting u'p a "preplanned" family fallout shelter. INDIVIDUAL PROTECTIVE MEASURES 10.52 The top of the storage unit should be hinged to the wall. In peacetime, the 10.58If the presence of fallout is sus- unit can be used as a bookcase, pantry, or pected before an individual can reach shel- storage facility. ter, the following actions will help minimize its effects. 10.53In a time of emergency, the storage unit can be tilted so that the bottom of 1. Cover the head with a hal, ora_pi it rests on a wall of bricks or concrete of cloth or newspaper. blocks that you have stored nearby. 2. Keep all outer clothing buttoned or 10.54Other. bricks or blocks should zipped. Adjust clothing to cover as then be placed in the storage unit's' corn- much exposed skin as possible. , partments, to provide an overhead shield 3. Brush outer clothing periiidically. against fallout radiation. 4. Continue to destination as rapidlyas practicable. 10.59 Assume that all persons arriving at a shelter or a fallout monitoring station after fallout arrival, and 'all individuals who have perl'ormed outside missions are contaminated. All persons should follow the protective measures below: . r. Brush shoes, and shake or brush clothing to remove contamination. This should be done before entering, the shelter area. 2. Remove and store all outer clothing in an isolated location. 3. Wash, brush, or wipe thoroughly, cpn- taminated portions of the skin and hair being careful not to injure the skin.

COLLECTIVE PROTECTION 10.60 buring fallout deposition, all windows, doors, and nonvital vents in shel- FIGURE 10.56.Covering base ment.wi ndows tered locations should be closed to control 155 151 the contamination entering th9'.' shelter. 5. Avoid unnacessary contact with con- Similar protective measures sh6uld be ap- taminated surfaces such as buildings plied to vehicles. and shrubbery. 10.61 :When radiation levels become 10.63Individiials using vehicles for measurable inside the shelter, make a sur- outside operations should remain in the vey of all shelter areas to determine the vehicle, leaving it only when necessary. To beist protected locations. Repeat this pro- prevent contamination of the interior of cedure periodically. This information is the vehicle, all windows and outside vents used to limit the exposure of shelter occu- should be close.d when dusty conditions pants. prevail. Vehicles provide only slight pro-

I tection from gamma radiation but they do provide excellent protection from beta and TASKS OUTSIDE OF SHELTER prevent contamination of the occipants. 10.62 When personnel leave shelter appropriate protective measures should be FOOD AND WATER taken to prevent the contfrmination of their bodies. Clbthing will not protect per- 10.64 To the extent practicable, pre- sonnel from gamma radiation, lnit will prevent fallout from becoming mixed into vent most airborne contamination from food and water. Food and water which is depositing on the skin. Most clothing is exposed to radiation, but not contami- satisfactory, hosiever, loosely woven cloth- nated, is not harmed and is fit for human ing should be avoided. Instruct shelterconsump4n. If it is suspected that food occupants to: containersNraicontaminated,Ihey should be waNhed or wiped prior to removal of the 1. Keep time outside of shelter to a mini- contents. Food properly removed from mum when exposure rates are high. such containers will be safe for consump- 2. Wear adequate clothing and cover as tion. much of the body as practical. Wear 10.65 Water in covered containers and boots or rubber ,galoshes, if a'vailable. underground Sources wiil be safe. Before Tie pants cuffs over them to avoid the arrival, of fallont, open supplies of Possible contamination-of feet and an- water such as cisterns, open wells, or kles. other containers should he covered. Shut ,3. A'void highly contaminated areas off source bf supply of potAhtiaily contami- whenever possible. Puddles and very .nated water. dusty areas where contamination is more probable should also be avoided. REFERENCES 4. Unger dry and duSty conditions, do ,not stir up dust unnecessarily. If The Effects of Nuclear Weapons.Glas- Idusty conditions mrevail, a man's stone, Samuel, 1964, ;hankerchief or a folded piece of Handbook for Radiological Monitors. closely woven cloth should be worn DOD/OCD, FG-E-5.9, April 1963. - over the nose and mouth to keep the In Time of Emergency, DCPA H-14, inhalation of fallout to a minimum. February 1977

t_,1!7' 0

,152 CHAPTER 11 -

RADIOLOGICALDECONTAMINATION

Although there are many formsof pro- water droplets. This material behaves tection against nuclear radiation,as we physically like any other dirt,or moisture. learned in the preceding chapter, theyare In fact, the phenomena of radioactivecon- obviously not foolproof. Even if theywere tamination is exactly the sameas getting 100% effective, there is still thecase of "dirty" EXCEPT that very smallamounts unavoidable contamination, contamination of "dirt" are required to producea hazard which could occur during theperformance and that the "dirt" is 'radioactive. of a critically important mission,contamination which ,could be deliberatelyand WHAT IS DECONTAMINATION? knowingly accepted. Obviously,then,. we need anothr RADEF tool to takecare Of 11.3 The objective of radiologicaldecontamination. That tool is DECONTAMI- contamination is to reduce the contamina- NATION and this chapter will explain: tion to an acceptable level withthe least HOWto tell if decontamination is possible expenditure of labor andmate- necessary rials, and with radiationexposure to decontamination personnel held toa mini- WHAT are the `steps in decontamina- IMum commensuratewith the urgency of don the task. RadioactiVitycannot be de- HOW does a decon workerprotect stroyed or neutralized, but in theevent of himself from contamination nuclear attack, the fallout radiationhaz, WHAT should be done todecontami- ard could be reduced by removingradioac- pate an area, a structure,an tive particles from a contaminatedsufface orange, somebody named and safely disposing ofthem, bycovering Henry, a cat, the powercom- the contaminated surface ivithshielding pany, a ,red sportshirt or a material, Such as earth,or by isolating a -farm tractor coniathinated object and, waitingfor the radration from itftodecrease thiough the INTRODUCTION process of natural radioactive decay, 11.4This ghapter is directed' te those 11.1Closely allied with the problem of persons who are responsible for planning monitoring, discussed in Chapter 9, isthe and establishing radiologicaldecontami- .problem of decontamination. Thetwo are, nation operations in States andlocalities. in fact, closely linked and cooperationand It contains guidanceon the yarious types coordination between monitors and decon- of decontamination proceduresand the tamination personnel isa basic require- relative effectiveness of each. ment if wasted effort orunnecessary hazard are to be avoided. , DtCONfAMI4ATION'OF' PERSONNEL AND CLOTHING- WHAT IS CONTAMINATION? 11.5State and local public welfare de- 11.2 As we saw in Chapter 6, theradio- partments and agencies, as the welfare % active fallotit froni a nuclear explosion arms of their respectiv,e governments, consists of radioisotopes that haveat- have primary resporisibility for planning tached themselves to- dust ,paiticlesor aod preparing the facilities anddevelop- /57 153 ing capabilities essential to provide emer- THE INJURED gency welfare at the local level. Voluntary social welfare agencies will assist. 11.9It is desirable that -contamination of medical facilities and personnel be kept 11.6Decontamination of personnel and at a minimum. Medical personnel, whose clothing of personnel engaged in recovery skills would be needed for the saving of operations would be the responsibility of lives, should be protected from radiation the various operational services, such as to the extent feasible. Persons entering a fire departments, police departments, and medical treatment station or hospital decontamination teams. Many persons shoulkbe monitored, decontaminated if would be responsible for decontamination necessary, Old tagged to show that he is- of themselves and their familieS in accord- not contaminated. To do this, a check point ance with instructions of the local govern- could be established at a shielded location ment. at each medical treatment Ikation and 1 hospital. Although decontamination procedures for the injured are the same as PERSONNEL those previously described for personnel decontamination (i.e., the removal of outer 11.7It is important that all people, and clothing, and other clothing if necessary, particularly those directing emergency op- and finally the washing of contaminated erations, understand that the total radia-%body areas, if required) special factors also tion injury from fallout is a composite due must be considered. In the face of urgency to several causes, including contamination for decontamination, there will be many of the surrounding areas, contamination casualties who are unable to decontami- of skin areas, iind ingestion and inhalation nate themselves and whose cohdition will of fallout -materials. -To keep the total ra- not permit movement. For...some- cases ae diation injury low, the effect of eaCh po- medical examination will determine that tential source of radiation on the total first aid must take priority over decontam- radiation exposure must be kept in mind, ination. Also, it may not be possible t) and each contributing element should be decontaminate some casualties without se- kept as low as operationally feasible. Nor-.riously aggravating their injuries. These mally,*ordinary personal cleanliness proce- will have to be segregated in a controlled dures will suffice for personnel decontami- area of the treatment facility. nation in the postattack period. 11.8All persohs seeking shelter after fallout starts should brush or shake their CLap.IING outer clothing before entering the shelter area. Ordiifary brushing will remove most 11.10 Thorough decontamination of of the contaminated material from the clothing cari be deferred until after the shoes and clothing, and often may reduce emergency shelter period when supplies of the contamination to, or below a permissi- water and equiment are available. Equip- ble level. It is important to brush or shake ment for decontamination of clothing in- from the upwind side. Under rainy condi- cludes whisk brooms, or similar types of tions, the outer clothing should be re- brushes, vacuum cleaners (if available) moved before entering the shelter area. and laundry equipment. For more effective decontamination of clothing, washer Upon entering the shelter area and as and dryer equipment should be available. soon as practicable, wash, brush, or,wipe Since there is normally little accumulation thoroughly the exposed portions of the of "dirt" in a washing machine, virtually body, Mich as the skin and hair. If suffi- all of the decontaminant would be flushed cient quantities of water are availahle, down the drain. The chance of significant persons should bathe, giving particular at- residual contamination of the washing ma- tention to skin areas that had not been chine appears to be qtkite ,small. Although covered by clothing. tz- 3 there is little serious danger involved in 154 washing, direct contact with the contami- for at least 2 weeks, since outside assist- nation should be kept to a miniumum. ance may not be available during this _ 11.11 The procedures for decontamina- period. tion of clothing should beas follows: First, brush or shake the clothing outdoors;sec- FOOD ond,.vacuum clean; third, wash; and fourth, if the previous proceduresare not 11.14 The following _guidance ispro- effective, allow natural radioactive decay. vided for individuals andgroups who need Monitoring of the clothingupon comple- to use food which may have been contami- tion of each step will indicate the effective- nated with fallout. Before openinga food ness of the decontamination procedure package; the package should bewiped or and indicate any need foil furtherdecon- washed if contamination is suspected. tamination. In many cases, depending Caution should be taken when yipingor upon the amount and kind of radioactive washing outer containers to avoid cptam- contaminant, brushing or simply shaking inating the food-itself. When possible, the the clothing to remove the dustparticles package surface should be monitored with may reduce the contamination to a negli- a radiation detection instrument before gible amount. If two thorough brushings removing the food as a checkon the effec- do not reduce the contaminationto an tiveness of the decontaminationproce- acceptable level, vacuum cleaning should dure. be attempted. Care should betaken in 11.15 Meats and dairy products that disposing of the contaminated material are wrapped or are Icept within closed from the dust bag of thevacuum cleaner. showcases or refrigerators should be free If the clothing is still contaminatedafter from contamination. Fallouton unpack- &ry methods of decontaminationare com- aged meat and other food items couldpres- pleted, it should be laundered. Clothing ent a difficult salvage problem. Fresh usually can be decontaminated satisfac- meat colloid be decontaminated by trim- torily by washing withsoap or detergent. ming the outer layers witha sharp knife. 11.12 Any clothing that stillremains The knife should be wipedor washed fre- highly contaminated should then bestored quently to prevent contaminating the in- to alloW the radioactivity to decay. Stor- cised surfaces. age, should be in an isolated locationso 11.16Fruits and vegetables harvested that the contaminated clothing willnot from fallout zones in the first monthpos- endanger personnel. tattack may require decontaminationbe- fore they can be used for food.Decontami- DECONTAMINATION OF FOOD, nate fruits and vegetables by wafhing the AGRICULTURAL LAND AND WATER exposed parts thoroughly toremove fallout particles, and ifnecessary, peeling, 11.13State and local public agencies, paring or removing the outer layer in such assisted by radiological defense personnel, a way as to avoid contamination of the will be responsible for the decontamina- inner parts. It should be possibleto decon-- tion of food and water. Stored foods in taminate adequately frUits, suchas ap- warehouses, markets, etc., will be there- ples, peaches,pears, and vegetables, such sponsibilitS7 of the agency controlling the as carrots, squash, and potatoes, by wash; distribution of the food items. Watersup- ing and/or paring. Thistype of decontami- ply personnel of the local governmentor nation can be applied tomany food items private organizations will be responsible in the home. for mbnitoring, and if required, decontami- 11.17 Animals should beput under nation of the water supplies they operate. cover before fallout arrives, and should Each personior family not expecting to be not be fed contaminated food andwater, if - protected in a 'community shelter, isre- uncOhtaminated food andwater are. avail- sponsible for providing, before attack, suf- able. If the animalsare suspected of being ficient food and water to supply its needi externally contaminated, They shouldbe 159 155 washed thoroughly before being-processed ,.because the contaminants would be incor- into food. orated into' their- cellular structure. Do 11.18 Even when animals have re- not destroy these contaminated foods. ceived sufficient radiation td cause later 11.20 4iming of acid soil will reduce the sickness or death, there will be a short uptake of strontium since .the plant sys- period (1 to 10 days following exposure, tem has a preference for calcium over depending on the amount) when the ani- strontium and has some ability to discrim- mals may not show any symptoms of in- indte. The plant's need for calcium leads to jury or other effects of the radiation. rfthe absorption of the similar element the animals are needed for food, if they strontiuni. In' soils low in exchangeable can be slaughtered during this time with- calcium, more strontium will be taken up out undue radiation exposure to the by the plant. By liming acid soils, more worker, and if no other disease 'or abnor- calcium is made avaijable to the plant, and mality would cause unwholesomenesst the less strontium will be absorbed. meat would be safe for use as food. In the 11.21Another methono limit the up- butchering process, care should be taken take of strontium is to grow 'crops with low to avoid contamination of the med, and to calcium content such as potatoes, cereal, protect personnel. The contaminated parts apples, tomatoes, peppers, sweet corn, should be disposed of in a posted location-squash, cucumbers, etc., on areas of heavy and in such a manner as to present a fallout. Other foods with high calcium con- negligible radiological or sanitation haz- tent such as lettuce cabbage, kale, broc- ard. If any animal shows signs of radiation coli, spinach, -celery, collardS, etc., could be sickness, it should not be slaughtered for grown in areas of relatively light fallout. food purposes until it is fully recovered. This may take several weeks or months. WATER Animals, showing signs of radiation sickness (loss of appetite, lack of.vitality, wa- 11.22Following a nuclear attack, water tery eyes, staggering or poor balance) in streams, lakes and uncovered storage should be separated from the herd because reservoirs might be contaminated by ra- they are subject to bacterial infection and dioactive fallout. The control of internal may not have the recuperative powers radiation hazards to personnel will be de- necessary to repel diseases. They could pendent, in large part; upon proper selec- infect other animals of the herd. tion and treatment of drinking water. 11.23If power is not available for pumping, or if fallout activity is too heavy AGRICULTURAL LAND to permit operation of water treatment 11.19 The uptake of radioactive fallout plants, the water stored in the homemay material would be a relatively long term be the only source of supply for several process, and the migration of fission prod- weeks. Emergency sources of potable ucts through the soil Ivould be relatively water can be obtained from hot water slow. Therefore, crops about to be har- tanks, flush tanks, ice cube trays etc. It is vested at the time fallout occurs would not advisable to have a 2-weeks emergency have absorbed great amounts of radioac-, water ration (at least 7 gallons per person) .tive material from the soil. However, if in or near shelter areas. crops are in the early stages of growth in 11.24Emergency water supplies may an intense fallout area, they will absorb be available from local industries, particu- radioactive materials through their leaves larly-beverage and milk bottling plants, or or roots and become contaminated. Thus, from private supplies, country clubs, and if eaten by livestock or man, it may cause large hotels or motels. some internal hazard. Before use, the de- 11.25If contaminated surface water gree of contamination should be evaluated supplies must be used, both conventional by a qualified person. Foods so contami- and specialized treatment processes may.- nated could not be decontaminated easily be employed to decontaminate water. The 156 160 degree of removal will dependupon the for decontamination of theirown vehicles nature of the contaminant (suspended or and equipment in accordance with instruc- dissolved) and upon the specific radionu- tions of local government. clide content of the fallout.. - 11.26 Radioactive materials absorbed EXTERIOR OF VEHICLES AND EQUIPMENT iii precipitates or sludges from water AND,VEHICLE INTERIORS treatment plants must lie disposed of in a safe manner. Storage in lowareas or pits, 11.29 The simplest and most obvious Or bdrial in areas where there is little method for partial decontamination ofve- likelihood of contaminating underground hicles and equipment is by water hosing. supplies, is recommended. Quick car-washing facilitiesare excellent 11.27Several devices for treating rela- for more thorough decontamination. tively small quantities of water under 11.30Special precautions should be emergency conditioni have been tested. used when vehicles and equipmentare mt Most of them use ion exchangeor absorp- brought in for maintenance. The malfunc- tion for removal of radioactive contami- tioning part of*the vehicleor equipment nants. should be checked for excessive contami- a. Small commercial ion exchange units nation. containing either single or mixed-bedres- ins, designed to produce softenedor demi- neralized water from tap water, could be used to remove radioactive particles from water. Many of them have an indicator, which changes the color of the resins to indicate the depletion of the resins'capacity. Tests of these units have indicated removals of over 97 percent of ali radioactive materials. b. Emergency water . treatnient units consisting of a colunin containing several a-inch layers of sand, gravel, humus, coarse vegetation, and clay have been tested for removal of radioactive materials FIGURE11.31.Equipment decontamination. from water. This type of emergency water treatment unit remov,ed over 90 percent of 11.31Hosing should not be usedon up- all dissolved radioactive materials. holstery or other porous surfaces on the c. Tank-type home 'water softeners-are interior of vehicles, as the water would capable of removing up to 99 percent of all penetrate and carry the contamination radioactive materials, and are especially deeper into the material. effective in the removal of the hazardous 11.32 The interior of vehiclescan be strontium 90 and cesium 137 contami- decontaminated by brushingor vacuuni nants. cleaning. Procedures for decontaminating interiors of vehicles by,,vacuum cleaning DECONTAMINATION OF VEHICLES AND are similar to those used orr the interior of EQUIPMENT structures. 11.28decontamination of vehicles and VEHICLES AND EQUIPMENT'USED BY equiPment of the various operationalserv- lees,,,such,as fire departments, police de- DECONTAMINATION PERSONNEL partments, and decontamination teams, 11.33 Upon completion of missions ina will be the responsibility of the various contaminated area, vehicles and equip- services, aided by radiological defense ment used by decontamination personnel sirvices. Individuals will be responsible hould be monitored, anddecontaminated 157 1 61 , if necessary. Complete decontamination moving the material from the surface to a may,not be necessary, but attempts should plaCe of disposal. Some decontamination be made to reduce the hazard to tolerable methods for paved areas are street sweep- levels. ing and motorized flushing. Firehosing 11.34 A decontamination station set up may be used for both paved areas and the at a control point adjacent to the staging exterior of structures. area would be the best place for decontam- 11.37Street sweeping is termed a dry inating vehicles and equipment. A paved decontamination method because water is area would be desirable so that it could be not used. There are many advantages of hosed off after the equipment is decontam- this method over wet methods. In the ab- inated. Monitoring should follow the appli- sence of adequate water supplies for large n of each decontamination method. scale decontamination procedures, dry street sweeping would be the preferred procedure. Also, during told weather, wet DECONTAMINATION OF VITAL AREAS decontamination procedures may not be AND STRUCTURES practical. 11.35 The operational planning aspects 11.38 Most commercial street sweepers of decontamina0on of vital areas and have similar operating characteristics. A structures are very complex and require powered rotary broom is used to dislodge trained decontamination teams from gov- the debris from streets into a conveyor ernment services, industry, and private system which, transports it to a hopper. and public utilities under the direction of a Thus, a removal and bulk transport sys- decontamination specialist. All methods tem is inherent in the design. Some swee- described in this chapter are common pers utilize a fine water spray to dampen techniques With which personnel of the the turface ahead of the pickup broom to emergency services are generally familiar. limit dust generation. This use of a spray Operational details associated with use of previous to brushing would reduce the ef- the equipment are not discussed. Howl. fectiveness of the procedure for decontam- ever, operational aspects peculiar to ra- ination because the combination would diological -recoverY are emphasized. The tend to produce a slurry which would method of decontamination selected will make complete removal of surface contam- depend upon the type and extent of con- ination more diffictilt. tamination, type of surface contaminated, 11.39 A variation in equipment of this the weather and the availability of person- type is the sweeper in wiiich the broom nel, material, and equipment. Each type of system is enclosed in a vacuum equipped surface presents an individual probleni and may 'require a different method of decontamination. The type of equjpment 'and skills required for radiological decontamination are not pew. Ordinary equipment now available,'such as water hoses, street sweepers, and pulldozers, and the skills normally usedLin operating the equipment are the basic requirements for radiological decontamination.

PAVED AREAS. AND EXTERIOR OF STRUCTURES 11.36Decontamination of paved areas and the exterior surface of structures requires two principal actions; loosening the fallout material from the surface and re- FIGURE 11.38,Commercial street sweeper. 158 4. t)0 using. The material pickedp by the method. The most satisfactoryoperating room and the dust trapped by he filtors distance from kozzle to the point of impact re collected_in a hopper. of the water stream withopen pavevients 11.40Normally a singleopera or is re- is 16 to 20 feet. On verticalsurfaces, the uired per street sweeper. Howeer, be- water should he directed to strike thesur- ause fallout material would beoncen- face at an angle of 300 to 45°. Asmany as rated in the hopper, the operatoray be three men per nozzlemay be required for jected to a high yadiationex ()sure. firehosing.- may make it necessary to rota eper- 11.46 When decontaminating rough nel for street sweeping operation . The and porous surfaces or when falloutmate- perator should he instructed to kep a rial is wet, the use of both firehosing close check on his dosimeter, and and dump scrubbing are recommended foreffective the hopper often at the predesignated reduction of the radiation hazard.Initial posal area, as precautionsto keep his ac- firehosing should be flone rapidlyto re- cumulated radiationevosure low. move the bulk of fallout material. Hosing 11.41In decontamiAating pavedareas f011owed-gy scrubbing wouldremove r..est by street sweeping, decontaminationfac- of the remaining contaminAtion.Two addi- tors' better than 0.1can be realized, de-tional men per hosemy be required for pending upon therate ofoperation and the scrubbing operation. the amount of fallout material. 11.47 Decontamination factorsbetween 11.42 The flushingor sweep'ing action 0.6 and 0.01 can be realized byarehosing of water is employed in decontaminatingtar and gravel roofs withvery little slope, aved areas by motorized flushing.Con- and 0.09 to 0.04 in decontaminatingcompo- entional street flushers usingtwo for- sition shingle roots that slope1 foot in ard nozzles and one side nozzleunder a every 21/2 feet. Decontamination factors of ressure of 55 pounds per square inch (psi) 0.06 can be realized in firehosing.ofpave- re satisfactory for this purpose. In flush- ments. i g paved areas, it is importantthat fal- 1 t material be moved towards drainage fa ilities. UNPAVED LAND AREAS 1.43, Decontamination factors of0.06 11.48 Decontamination of unpavedland to u .01 can be realized by motorizedflush- areas can be accomplished by removing ing, depending upon the rate ofoperation the top layer of soil, coveringthe area and he type and roughness ofthe surface. with uncontaminated soil,or by turning 11. if The flushing oresweepingaction the contaminated surfaceinto the soil by of water also is used in decontaminating plowing. The two latter methodsemploy soil as a shielding material. paved areas and the exterior ofstructures by fir hosing. Equipment andpersonnel 11.49 The effectiveness ofany of the are co monly available for this method. -methods is dependenton the thoroughness Employ ent of the method is dependent with which theyare carried out. Spills ur upon an \ adequate postattack watersup- misses and failure to overlap adjoining ply. Whedecontaminating paved areas passes should be avoided. Reliance should and struct res, it is,important thatfallout be placed on radiation detectioninstru- material bswept toward predesignated ments to find suchareas, although in drainage f cilities, and, where possible, heavily contaminatedareas the fallout downwind fr m operational personnel. material may be visible: Large spillsor 11.46 Standard fire fighting misses should be removed bya second pais equipmenLof the equipment. Small and trucks equipped with pumpingappa- areas can be de- ratus may be 4sed in this decontamination contaminated with theuse of shovels, front end loaders, and dump trucks. . 11450Large scale scraping ' For decontamination of vital areas and.structureathe term decon- operations tamination factor (11F) is used This represents the decimalfraction reqd-lre heavy motorizedequipment to remulnlflX after decontamination is accomplished. scrape off the top layer (several inches) of 113 159 ,nated soil stripped, off by abulltrocer should be deposited at tile outer edge of -`8 the scraped area, or beyond, if prvticable. 11.53Filling nray offer no advantagf over scraping, either in, effectiveness or speed, Its principal use would behere scraping procedures could not be/u5ed, either because of rocky ground or,kfecatise 'L of permanent obstructions. Fill' g can be b used in combination with oth9f methods to achieve a low decontaminati n factor. The object of filling is. to covethe contami- 14111, nated area with uncontami ated soil or fill material to provide shiel mg. For these' operationka motorized scraper, bulldozer,, FIGURE 11.48,Turning contaminated soil. mechanical shovel, or dump trubk and grader may be used., ocontaminated soil, and. carry the soil to 11.54 'The effectiveness of rela- suitable predesignated dumping grounds. tively flat surfaces will vary with the 'The contaminated soil should be deposited' depth of fill. A 6-inch fill of earth can 100 Or more _feet beyond the scraped area reduce the radiological hazard directly irposiible; if not, at least to the outer edge above, ton decontamination factor of 0.15, of the scraped area. Scraping can be done and a 12-inch fill can redlice the hazard to with a motorized scraper, motor grader, or bulldozer. Effectiveness of the procedure a cicontamination factor of 0.02. depends upon the surface conditions. In 11.55Plowing prOvides earth shielding decontaminating unpaved areas by scrap- from radiation by turning tbe contanti- ing, decontamination factors over 0.04 can nated soil under., It is a rapid rneam1/4 of be realizecl, if all spills and misses are decontamination, but may not be suitable cleaned up. in areas in ,which personnel must oAeraie 11.51The motor grader is designed !qr.,or travel over the ploweg surface. Me grading operations, such as for spreading depth of :plowing should be frOm 8 to 10 soil or for light stripping. This grader can inches. In decontaminating unpaved livid be'etffecive1y on any long marrow nreas by plowing, decoptamination lactor$ area where contaminated soil. can be of 0.2 can be realized if the depth of plo* dumped along the edge of the cleared area. ing is from 8 to 10 inches. The blade should be set at an angle Suffi- 11.56 Two or more methods can be-ap- cient for removing several inches of the plied in suCcession, achieving a reduction contaminated soil. The scraped Up earth in the radiation field not possible, practi- should be piled along the ground in a cal, or economical with one method alone. windrow parallel to the line of Motion. The Any of three combinations of methods-7 windrow can be either pushed to the side scraping and filling, scraping and plowing, of the, contaminated field and buried by or plowing, leveling!and fillingcould" be the grader or removed by other pieces of effective in unpaved areas In solpe cases, earthmoving equipment. any of the three might be more ra icIthan 11.52 The bulldozer can be useful in individual remoylit of spillage: Th equip- scraping small contaminated areas, bury- ment used would be the same as in c mpAt- ing material, digging sumps for contami- nent methods Previously discussed. nated drainage, and in back;filling sumps. 11.57 Becauselarge earthmoving It would be' particularly suitable in rough equipment could not be used in Oman terrain where it could be used to clearareas, such as those around a building, ,obstructions and as a prime mover to as- othe: methods of decontarnination must be sist in motorized scraping. The contami- used. If the area is ldrge enough for a , 160 C 4 *small garden typetractor, or 11.60 The principalAold loaders,: these can be uSed fer wealther decon-11 plo ing and tamination methods for pavedareas, and scraping the soil. Improvisedmethods of structures are: (1) Snow loading, serapint small areas, such (2) sweep- as using a jeep ing, (3) snow plowing, and(4) firehosing. to tow a manually operatedbucket scoop, X461 Snow loading, isaccomplished --'--could -be -used: Tfrere-Would ieinain sonte with -a front-end leader areas. requiring hand labor with shovels, and is applicable to dig up or.iemove the'top layer for snow'covers.: Whenfallout is on snow, of soil, or the front-end loaderbucket is used to sod. Equipinent andmanpower require- scoop up the contaminant' andlop ,ments for-loading and haulingthe soil-to a layer of snow, which are ferced into the bucketby disposal area should beincluded in esti:the forward mOtiOn of mate of decontamination "costs".The the .vehicle. The rates of operation of these methods snow cover sheuld be observed closelyfor would pieces of contaminated debris ',vhich ..Vary with the type of terrain.and may its vege- have penetrated tosome depth. The-loader tative cOver. The variousprocedures can result in decontathination factors carries the contaminatedmateiial to ,a of 0.15 to dump truck whichremoves it to a duniping area. The 'remaining 'cleansnow is removed by normal snow-removalproce:. INTERIOR OF STRUCTURS dures. DecontaminationJactorsof appro)fi- el* . mately 0.10 can be realiied by- thisprocess, ,..4:111313The two principal methodsfor de- ,. depending mainly Tel--theamount-of spil, ft contaminating interiors ofstructures are lage. vacuum cleaning and scrubbing Withsoap and water:Vacuum cleaningis useful for the decontaminationof furniture,rugs, and floors. Floors, tables,walls, and other surfaces can be decontaminatedby scrub- .bing(th-e-"i)t withsoap and water. Mild detergents can be substitutedfor soap. Rags, - hazid brushes (otpower-driven rotary brushes, if available),mops, and brooms are suitable for scrubbing.

COLb WEATIERDECONTAMINATION PROCEDURES 11.59pold weather .deconbapation, methods will depend upon the weather FIGURE11.61,Front-end loader. conditions prior to and afterthe arrival of fallout.:Yarious problems suchas fallout on various depths of snow, on frozen 11.62 Pavementsweepers cabe died -: ground 9r pavement, mixedwith snow or for fallout on dry-paveinent, freezing. rain, and under various traffiepac,ked depths of snow, or reasonably leVel-frozen soilor ice. snow could occur after a contaminating Pavement sweepers,are more effective attack.' The iiresence ofsnow or ice would than firehosing wherethere is a drainage complicate the situation 'since largequan- problem, or whe,n tities of these materials would temperatures are frlow. have. to be Sweepers will not effectivelypick up con- moved along with the falloutmaterial. In taminant on wet addition, snoW anrze-coUld pavement above tlje cause loss of freezing or slush pointon ibe or pa'cked m9bility to men and to equipment.Fallout snow. Decontamination factprsare ap- may bd clearly visibleas a dark film or proximately 0110. layer of soil or powder on or within snow 11:63 Snow plowing is unless it precipitates with thesnow, applicable for all depths of contaMinatedsnoW. When fat- 461 p 185 lout is iiieCipitated with snow,. all of the rates, and the decontamination factor snow must be removed to the dumping will vary from 0.5 to 0.1. area. Blade snowplows, road graders, or 11.65In small areas, such as roofs of bulldozers in echelon,' windrow the con- bliildings, and around buildings, where _ taminated snow to qne side until the blades large snow remoVal equipment could not are stalled by the snow mass. A snow be used, other methods of decontamina- loAder can be used to put- the contami- tion must be used. With small amounts of nated snow in dump trucks, which move it dry snow on roofs or paved areas, sweep- to tlie clumping area., Decoptamination ing, the area with .brooms is satisfactory. factors 44 0.15 can be realized by this With larger amounts of snow, with the _ method. fallout material on top of the snow, or 11.64Firehosing is Dossible and can be mixed with the snow, shoveling the snow used on paved areas and exteriers,of and removing it to an area where large strUctures slightly below freezing temper- snow removal equipment can be used is atures. Pirehosing is npt recommend d piacticable. The ratespf operation of thes-e- where slush from snqii will clog drain methods Would, vary with the amount of Problems associated with firehosing below snow to be remolied 'aud the type of sur- 32° F are freezing of the w'ater, thereby face to be decontaminated. 'The.,yarious sealing the contaminant in ice and caiising rocedures can result in decontamination Slippery conditions for the operating per- etors of 0.1510 0.1. sonnel. The principle of operation, and 11.66In order to locate needed services equipment used° in temperate weather, .and to guide the movement of decontami- will be the same under cold weather condi- nation equipment (through .heavy snow tions. The effectiveness of firehosing will covers, cololed poles should mark street depend on surface and standard exposure corners, drains, hydrants and hidden ob- .

AGEN4 ' TYPE OF SURFACE' SITUATIONS

c . iTEAM, PAINTED OR OILEDi NONPOROUS ROOMS WHERE CONTAMINATED SPRAY _CAN . BE CONTROLLED. BOILDNGS; . . . -...sl%

SURFACE COVERED WITH ATMOSPORIC NON-POROUS '(METAL, PAINT, PLASTICS:- DETERGENTS DUST-AND GREASE. FIXED OR MOVABLE ETC.). INDUSTRIAL 'FILMS,OILS,thGREASES. , . ITEMS. - LARGE , UN WEATHERED SURFACE. SURFACE-Si COMPLEXING - METAL OR PAINTED. -WHERE CORROSION IS NOT TOLERABLE.' AGENTS -f_AS-AN:ADJUNCTTO WATER. OR STEAM

1 TRE-ATMENT.' 1

* ORGANIC FINAL CLEANING. WHERE COMPLETE IM- PAINTED OR GREASED. SOLVENTS MERSION DIPPING OPERATIONS ARE -. POSSIBLE. MOVABLE ITEMS. T..

, METAL OR PAINTED;tSPECIALLY THOSE * INORGANIC ACID EXHIBITING' POROUS DEPOSITS, SUdiiAS DIPPING OF MOVABLE ITEMS. RUST, MARINE GROWTH. ..

* CAUSTICS PAINTED. . LARGE, SURFACES. DIPPING OF PAINTED OBJECTS.

ABRASIONS METAL AND PAINTED LARGE, WEATHERED SURFACES. FIXED OR MOVABLE ITEMS.

* UNUSUAL HAZARDS ARE ASSOCIATED WITH THESE METHODS, AND SPECIAL PRECAUTIONSOR PROTECTIVE EQUIPMENT AND,REQUIRED. , . 1 FiGURE 11.67.Small scale decontamination methods. stacles. Open ground areas planned for REFERENCE postattack use should be clearedof rocks, stumps, etc., prior to thearrival of snow. Decontamination Considerations For 11.67 Figure 11.67lists other decon- Architects and Engineers, DCPA TR 71 tamination method's thatmay be used on a 1976 small scale, for specificareas of high contamination.

,..

41%

a."

H_ 163 .4. 0to CHAPTER 12

RADEF OPERATIONS_

The man-in-the-street often thinks of ries. As a consequence, effective RADEF modern war a,s "push button war" with countermeasures demand cooperation Visions of all our forces moving automati- vong the various RADEF crfanizations. cally at the pressing of a button on' the This cooperation must beboth horizontal President's desk. This just isn't so, of and vertical: horizontal among organiza- course. If there is no' such thing as "push tions on the same level of government button war", how Much more so is there (e.g., different 'counties or States); vertical no such thing as "push button radiological among levels (e.g., city and State). Also, defense." We may have sensitive machines cooperation must not wait until an at- and instruments to measure nuclear ra- tackit must be planned for and worked diation, but these devices must be, operat'noia. ated/ interpreted and the information acted upon. It is the prime objective of this chapter to exPlain how and by whom WHO WILL CARRY OUT RADEF RADEF operations are carried out, and OPERATIONS? how the responsibilities for such opera- 12.4 To carry out the various funeions tions vary among different types of of radiological defense, there is need for RADEF personnel and within the various Radiological Defense Officers, Assistant levels of government. Radiological Defense Officers, Monitors, Analysts, and Plotters. The following par- INTRODUCTION.- agraphs define each of these positions and summarize duties and responsibilities. 12.1To be effective, radiological de- These definitions are necessary at this fense countermeasures require rapid de- point to avoid repetition in the later level- tection, measurement, reporting, plotting, by-level description of the operational analysis, and evaluation of fallout contani- process. ination for use during the early. period after attack and trained radiological personnel are needed at all levels of the gov- DEFINITIONS ernmentFederal, State, and local, to pro- 12.5Radiological Defense Office);.A vide such information and skills. person who has tieen trained to assume 12.2 The RADEF Officer and other the, responsibility for policy recemmenda- RADEF personnel, in carrying out their dons for the radiological defense of a responsibilities, act in a "staff" rather State, county, locality, facility, or a rela- than in a "command" capacity. They pro- tivelyiargegroup of organized personnel. vide an important part of the technical This officer must be conyersant with information upon which Civir Prepared- measurement and reporting protedures, ness command decisions Will be based. capable of evaluating the probable effects 12.3It must 'be stressed that thouglxof reported radiation on the people and RADEF prsonnel serve in a staff capac-'their environment, and capable ofrecom- ity at the various levels of government, mending appropriate prOtedive measures fallout radiation, is a physi,cal not apoliti-Istich as,.ernecrial mover/lent, shelter, an canhenonienon. Ii) short, fallout doe's not decontanunatton) tbitaken as a result of recognize city, state, or county bounda- the evaluation. 164 1 r. 12.6 Assistant RadiologicalDefense 01.- PORTS .vhen'ever)a declining rate.trend is ficer.Definition similar to that ofthe reversed and there is a rapid increase. Radiological Defense Ofic Less admin- 1' istrative capability is.require, ut the NOTE -capabilities- iMechabove d'te F'or thc monitoring station, and for all should be borne in mind thatthe .term levelsythe time before fallout arrivesis "assistant" is an organizational di4inc- a time of intense activity. Notra motion rather than indicative of anything ment should be log' by RADEFperson- less than 100% possession of allnecessary nel between afrivta at assignedloca- RADEF Officer qualifications. tions and performanceof all prescribed "12.7- Monitor.A readiness actions. ... person who has been trainvd to detestjecord, andreport radia- *12.11 Shelter monitoringactivities. tion Otiposures andexposure rates. He will Aftet checking hia equipment,the shelter provide limited field guidanceon radiation Monitor will make an operational -readi- hazards associated with operationsto ness report to the shelter manager (who, Which he is assigned. in turn, will report that factto the EOC). 12.8 Ana/vatAperson who has, been The shelter monitors willmeasure and trained to prepare monitoredradiological report to the sheltermanager the daily data in analyzed form foruse in the area cumulative exposure of shelteroccupants. served as well as by other levels ofgovern- Thjs in-shelter exposure will bereported ment to which reports of such dataare to the EOC if it exceeds 75 R. Shouldthis sesty.1:givill also evAluate theradiation be exceeded during the firsttwo days in de tierns as a basis for estimates of shelter, or_ should theexposure rate ex- future exposure rates and radiationexpo- ceed 10 R/hr, an EMERGENCY REPORT ., sures associated with emergen-eyopera- should be sent to the EOC requestingad- tions. . -vice. The shelter monitor willalso report 12.9 Plotter.A person trainedto re--to the shelter manageras to the daily cord incoming data in appropriate tabular exposure rate. Should any occupied area of form and to plot such dataon maps. He the shelter be receivinga fire" of 2 R/hr or will also perform routine computationsun- more, the monitor will'report on theexpo- der direction. sure rates within various areas of the shelter so that themanager may move sheltercupants to safer positions in the LEVEL7BY-LEVEL RADEF OPERATIONS sher. The shelter may also be desig- na as 12.10F'qllout monitaiing station activi- station in the regulak monitor- ties.Upon receipt of warnink ing netw which instance the opera- of likely tioneescrib in paragraph 12.10 will attack, monitors (at leastfour should be also be performed. assigned to each station to-provide24-hour continuous monitoring), will beadvised of 12.12 The Ideal the likelihood of attack. They emergency operating will then center.Local emergency operatingcen- begin to carry out theemergency plan. ters first determine that monitoring Upon arrival at the monitoring sta- station, all tions are in a state of operationalreadi- equipment and procedui.es shoUldbe chalked and ness. Subsequently, the local EOC's will an operational readiness re- receive reports from these monitoringsta- polt made to theemergency operating tions and shelters and willtransmit sum- center (EOC) RADEF Officer,thuslrerify- mary-type data to the State EOC. In addi- ing that the station is readyto opeiate. tion, and as previously agreedupon, this The monitoring stAtion will sendthe EOC data, can be made availableto neighboring a FLASH REPORT the first time the uric- EOC's. The eeports to the StateEOC will sheltered exposure rate equalsor exceeds include flash reports made.a_pon their re- 0,5 R/hr. The station alsmendsseheduled'ceipt-from aity of the monitoring EXPOSURE stations RATE REPORTS and EXPO- within the network of the localEOC. Expo- SURE REPOIO'S, plus SPECIAIrRE- ,---inirmd exposure rate reports willalso be 165 1.("' Q --/ made in summary form .to the State EOC RADEF system through the DCPA re- as determined by the State Civil Prepared- gions to which they report. neth Plan. The exposure rate report will 12.14In addition to collecting and re- include a-typical exposure rate if the area porting data, RADEF Officers at the State within the jurisdiction of the local EOC is (sometimes sub-State) level have :the re- small. The local EOC's will also report the sponsibility of providing the data for fal- accumulated unsheltered exposure at lout warning and other fallout advisories least once each day to the State EOC. It issued to the general j2opulace by the Gov- should be noted that the term "local EOC" ernor or other properly, designated civil ig used here to designate the operating authority. There are many possible types echelon or echelons between the monitor- of advisories which could be issued de- ing 'statioN and the State EOC. (A very pending upon local conditions. large gity.may_baxe.local area EOC'sSand- ---wiched- in between the stations and the EMERGENCY OPERATING CENTER local EOC's.) In addition, some States may PERSONNEL have county EOC's between the local and _State .EOQ's...Tbese various EOC's may 12.15Communities over 500 population, report to a:gab:State EOC depending on State and county governments, and cer- the State's-geography and population. tain field installations of Federal agencies 12.13The State Emergency Operating require other radiological defense person- Cente.r.This _is_ the commons' level for nel in addition to monitors. These are the each State's Civil Preparedness organiza- RADE-F- Officers, Assistant RADEF Offi- tion. The State EOC receives reports from cers, Plotters, and -Analyst.b -located at-- local, local area, county and/or sub-State EOC's. Their functions were summarized EOC's within the State and will, in turn, in paYagraTh-Thrt2:rtinZa."-As irrule, rural send to the approprjate DCPA regional areas will need only monitors. The number offrce flash reports summarizing the of Assistant Radiological Defense Officers spread of fallout across the State as well will depend on community size. Large ci- as exposure rate analyses. The State EOC ties will require several, while small com- will also send selected flash reports as munities may require none, appropriate to the local EOC to alert them 12.16 A suggested guide to the number __DLapproaching fallout and exposure rate of Analysts and .Plotters for communities reports to advise local centers of exposure of various sizes is shown in Figure 12.16. A rates in neighboring communities. Neigh- Radiological Defense Officer can "double boring States, in addition, and Canadian in brass," filling in for a variety of RADEF provinces can also be sent flash repor,ts personnel where no other individual is and exposure rate analyses by the State available to perform the particular func- EOC. State EOC's tied into a national trim.

PLOTTERSANALYSTS POPULATION- NEEDED NEEDED

Under 2,500 1 1

2,500 to 25,000 1 1 25,000 to 250,000 4 2 Over 250,000 6 3

tat -

. . FIGURE 12.46.Requirements guide for p14ters and analysts.

166 .) 1

NOTE linked into a well organizedand extensive This 4.-s a "one-way street,"however, reporting system, runningup through the becausean analyst for example,CAN- sub-State and State organization NOT perform the...frnctionsof a Wa- all the diotogecal Defense Offiesrunless he IS .way to-the national center. It is vitalthat a Radiological Defense Officer. the data. produced ateach level should support the higher levels. Also,data must be consistent between andamong report- A REPORTING NETWORK ing levels. No correcCconclusionscan be 124/ The monitoring stations drawn from data thatemploy different, must be units of measurementor time bases.

I "7

167 1.

CHAPTER 13

RADEF PLANNING

In a church in Caracas, Venezuela, a was held by one of the participants in the pickpocket, hoping to stir up some excite- experiment. The idea, of course, was to ment, duiiing -which he could work more pull the cones out of the bottle. When ea*, shouted "Fire." There was no fire conditions such as we might have during a but the congregation stampeded anyway. sudden emergency arose and there was When the screaming mob finally burst out "every man for himself", traffic jams oc- of the church, many huddled forms were curred. Sometimes but one or two cones left behind, trampled and broken. Fifty- were jerked free before the rest were -three of them, including 22 children, would hopelessly snarled. never discover that there wa.s.no fire. But, when the participants were given After the Titanic smashed agai,st an time for prior consultation and planning, iceberg a Mrs. Dickinson Bishop left $11,- there were no trahic jams. In one instance 000 in jewelry behind in her stateroom, all the cones were removed in under, 10 but asked her husband to dash back to seconds.i. pick up a forgotten muff. Another passen- 13.2 But what happens when there are ger_ on the sinking vessel, Major Arthur no plans? We saw the experimental evi- Peuchen, grabbed three oranges and a dence. Cones get jammed. Strings get good-luck pin, overlooking $300,000 in se- twisted. The evidence of real life is just as curities he had in his cabin. Still another simply stated: people get killed and in- passenger carried into the lifeboat nothing jured; property iets destroyed. li,is said but a musical toy pig. that casualty statistics are people with the There are, 'countless cases of persons tears wiped off. Let's look behind the sta- who in their haste to escape hotel fires, tistics and examine a few of the legion of jump from upper story windows located tearful stories. justfew feet from a fire escape. The cause of this strange and illogical THEY HAD NO PLANS behavior is panic and the cure is planning. 13.3 A bustling city of -30,000 was lc= The major objective of this chapter is to cated at the point where two swift streams describe the importance of planning to met. The city was built along the low river effective Radiological Defense. , banks, surrounded by .steep hills. As a result of this situation, the lower pait of THE EXPERIMENTAL EVIDENCE the city suffered from floods every spring. 13.4Upstreanf was a huge dam, origi- 13.1In a series of 42 iaryinexperi= nally built to gtore water for a cAnal but ments With from 15 to 21, subje ts, the %. . -Nprogress made the canal uneconomical, so psychologit Alexander Mintz clearly It. was abandoned and maintenance halted showed the yvide differenc,e between on the dam. Gradually the dam deterio- planned and unplanned 'behavior in a pe- rated. Water seeped out in a hundred pla- riod of stress. The experimental situation ces and within a few years the water level conSisted -of a large glass bottle with a had dropped to half...When a small break narrow mouth. Inserted in this bottle were - a Rumber of aluminum cones. These cones ' Nip-Adaptive Group Behavior, Alexander Mintz, Readings in Social were attached to strings each _of which, Psychology, p. 190-195, Hehry Holt & Co New York, 1952

16$ " 9 btcurred, the water levelwas low and only part of the city hours later in a devastatedcity, ravaged was flooded. to the tune of 552 dead, 13.5Subsequently, 3,000 injured and a hunting and fish- maimed and over$50,000,000 in property ing club leased thedam and the lake it damage. impounded. The clubtried to repair the dam. Their work seemed 13:11It all began witha few w of sound. But into smoke froin the the break had beendumped tree stumps, cargo of fertiffier carried sand, leaves, straw and on board the SS Grandeamp.A crewman other debris. Later investigated, but on, heavy rains caused many leaksin the even after shifting sev- dam and floods inthe city. eral bags of thefertilizer, he could find 13.6 nothing. He triedthrowing buckets of Finally, therewas an even heavier watec in the, direction rainfall. After six-inchesof rain, the water of the smoke. No level in the dam effect!. -Next he trieda fire extinguisher. rose rapidly. Crews hired Still- no effect. So Iaecalled for:a fire-hose. by ihe hunting and fishin'gclub workedto repair the leaks but 'But the foremanobjected. Hosing down therising waters kept the cargo would ruin eating away at therotten structure. it. The Captainor- dered the hatchesbattened down and the 13.7Finally, a civil engineerinspected turning on of the the dam. He realized it steam jets. Turningon would not hold and steam to "fight fires isstandard marine tried to get word to the,city below. There firefighting Practice, and were no telephones and the has been for storms had years. But this fertilizerwas ammonium downed the telegraphwires. Word did not nitrate, which, when get through: MeanWhile, heallbd to about 350 the workers degrees Fahrenheit,becomes a high explo-. watched in horroras the waters began to sive. roar over the tppof the dam racing for the 13.12 Someone 'ciry, 12 milesaway and 400 feet lower in should have knownhow elrvation. to deal with thisexplosive fertilizer.Some- one should have made plansfor putting mit 13.8 A half millioncubic feet of water a possible fire in rushed through that or near the nitrate,. But breach oickingup on no one had. Andso, at 12 minutes after 9 the way trees, houses,boulders. When it on the Morning of April reached, the city it'was 16, 1947, the 10,- a wall 30 feet high 419-tog Grandeampand all those aboard moving at- 20 milesan hour. The result: were blown to bits. The annihilation! The citywas destroyed, and lated as equivalent explosion, calcu- 2,000 people lost theirlives in an instant of to 250 five-ton block- terror. busters (1.25 kilotons)goingff at once, dropped 300-pound 13.9 But the pieces of lhe Grand- disaster'need never have camp 3 miles away. Twosm ll planes, happened had thewarnings of the dam flying at about 1,000 itself been heeded feet above he harbor during the preceding disintegrated from thdtronen ous con- quarter century. Even ifno efforts had cussion. The blastswept across çhe been made toremove the causethe ob- plex of oiI refineries com- viously unsound condition and chemica plants, of the damit smaihing them flatand settingo f other seems unbelievable thatno one planned exPlosions and fires. for a possible serious _ break, and noone 13.13 As a result planned a warningsystem. of this explosion and the later and evenmore violent blast from AND STILL NO PLANS another ammonium nitrateladen ship, the SS High Flyer, chaosreigned in Texas 13.10 But we neednot go all theway City. Though the citizensof_ the city back to the Johnstownflood to see the worked withcourage and initiative to help effect of lack ofplanning. The greatest the injured, for thefirst few hours their manmade disaster inrecent American work was uncoordinated. history;is replete withexamples of lack of 13.14 Thve wasno disaster plan. planning, from its ,beginningsin the hold 13.15 The head of of a sh.ip in GalvestonBay to its end the Texas City disas- a few ter organization isquoted as saying: "We 169 _ had an organization, but it was designed ning is summed up in a straight-from-the- for hurricane. We weren't prepared for shoulder report of the National Fire Pro- anything like this. In a hurricane, you tection Association: have some warning and' you can get your "The fire-spreading conditions aboard organization ready. But we had no warn- this vessel had been allowed to become ing in this, and our organization was scat- so bad during the egecution of a $4,000,- tered all over town. And do you know what 000 conversion contract that a wayward happened at our meeting to develop a dis- spark from a cutting tool, inexcusably aster organization just 3 weeks before the landing in a kapok life preserver, was ,explosion? People pooh-poohed the idea!' sufficient to culminate in the total destruction of an uninAred $53,04000 .MORE. LACK_OF PLANNING, ship. Because although the incipient 13.16 On September 5, 1934, the SS outbreak started in broad daylight un- Morro Castle steamed out of Havana har- der the eyes of 1,750 employees of the bor. A seagoing hotel, the ship was contractorplus another 1,650 Navy, crammed with passengers heading back to Coast guard and subcontractor person- New Yort after a Carj4ean vacation. The nelnot one of them had the rudimen- ship wai equipped with all- the latest tary training required to stop the ecluipment to detect, cpnfinand extin- thingor -eVen the wit to promptly call guish fires. in somebody with the training. By the 13.17 Captain Wilniott was confident in time,..the fire department was sum- the fire safety of his ship: But 2 days later moned, the blaze had advanced so far he was dead of a heart attack and his that a fifth alarm was required, putting second in command had scarcely gotten to work more apparatus than is owned accustomed to being Captain wherl a deck by cities the size of St. Paul, Minn., or night watchman reported a fire. Toledo, Ohio." 13.18 After investigating, a belated alarm was sounded arld the crew tried to 'A FINAL TRAGEDY put out the fire. The ship was equipped 13.22Finally, there was the Coconut with fire doors which, if shut in time, Grove fire. , might have kept the fire from spreading 13.23 The Coconut Grove was manY past the point If origin. things. It was a fire trap infested with 13.19 But nj one had been assigned to safety violations (for which the owner was close the fire doors. . later sentenced to prison for from 12 to 15 13.20This, and other evidence of seri- years). If was the last hour for 450 per- ous planning deficiencies, caused the Act- sons. It was also an example of lack of ing Captain and Chief Engineer to be sent- planning, from the major, exit door that enced to prison for incompetence and ne- opened inward (where some 100 bodies glect of duty (they were later cleared by a Were found jammed), to the narrow stair- higher court) and the steamship line was ways, to the inflammable decorations, fined $15,000 for failure to enforce safety even to the lack of planning in sending the regulations and for placing iniqualified victims to hospitals. personnel in charge of the ship. The final 13.24BOston's City Hospital received cost was 134 dead and $4,800,000 property 129 fire victims, thus greatly overloalding loss. 'its facilities. Massachusetts General Hos- pital received only 39 and could have han- ANOTHER CATASTROPHE dled many more. Thirty other victims were 13.21Or take the case of the former distributed arhong 10 other civilian hospi- French liner Normand:ie. The lack of plan- tals. Seventy-eight percent were sent to \ City Hospital simply because that is where accident victims usually were sent. 'Quoted in THE FACE OF DISASTER, Donald Robinson. p. 130. Doubkday & Co., New York. 1959. 13.25 Na one planned for the disaster when masses of peoplewould simultane- all of the of ously, become the victims u into some 3 or 4 years of accident. of intense raining andplanning paid off. When it was needed, theorganization was ....THEY HAD PLANS- -ready to foll-titwas only a matter of calling the staff together 1:3.26When an explodingammunition and giving them _ship faced SouthAmboy, N.J., with the _the job."3 same situation as Texas City,the mayor had a disaster plan allset to go. Immedi- EMERGENCY VERSUSCATASTROPHE ately the rescue operationwent into high gear. 13.32Despite differences indictionary definitions, often the only 13.27 Men knew where real difference .. they were sup- between an emergency anda catastrophe _p.osqd. t? go, and -they-wentthere:-Off-duty-ispriorplanning. pace were automaticallycalled in. Road 13.33 blocks controlled traffic Perhaps the best concreteexam- keeping the sight- ple is the damagecontrol system used by seers out and letting reliefsupplies in. Liaison was established, all major modern navies.Naval combat per plan, with the ships are not designedfrom the standpoint State Police and theNational Guard. of wishful thinkingoptimisticallyhoping 13.28 The propertydestructiOnat that there will be South Amboy no hits and do_ damage. was nearly as greatas -at Rather, naval vesselsare designed with Texas City ($36,000,000)but the loss of life the' point of view th4t theship that can was far less (31 dead): take the most' punishmentand still fight on is the ship that will survive andwin PLANNING PAYS OFF victory. Hence, naval combatvessels have elaborate, butvery practical, damage 13.29 In whatwas termed "the mostcontrol systems. Thesesystems include successful exercise... ever heacd of in watertight compartments of the United States", various sizes, some 200,0V people provisions for pumping, forcounter-flood- evacuatfd low lyingareas on the Texas ing to restore balance, coast to avoid hurricane of standby and Carla. auxiliary power, intensivetraining and ef- 13.30 The succeSs andsmooth function- fective organization of thecrew, and many ing of this giganticmovement had many other features. All theseare the result of reasons. According to the Gov\ernor.of the analysis of thousandsof accidents at Texas, "Thesuccess of evacuation was the sea, naval engagements, and justplain result of careful planningwhich began 10 hard, logical thinking.Thus, when a ship years ago in the Governor's officewhen its slides down theways it is the product of Division of Defense andDisaster Relief countless plans, not thelast of which is `.was set ap." A Red Cross officialadded, planning to keepan emergency from turn- ..critics said theGovernment was ing into a disaster. pouring money downa rathole (for planning). It wasn'titwas this plan we were AN IMPORTANT LESSON able to use. The State has a CD plan and 13.34 You might well made the plan workthatis .why we were wonder what the able to do so much"... preceding paragraphs haveto do with ra- 13.31- The head diological defense planningas such. How of the Texas Depart- does the Morro Castle, ment of Public Safety,when asked why the Coconut Grove, the operation bad been our Navy's damage controlsystems, or such a resounding Johnstown, Pennsglvania, success, answered, "Why? Itwas done be- relate to the cause of preplanning and problems of planningforivil prepared- training". A ness; what do the explosivequalities of county judge added, "Letpeople know the ammonium nitrate have value of preplanning":In Louisiana, the to do with de- Lake Charles Civil DefenseOffice stated 'Quotes from Department of cane Carla p 93 SupermtendentDefense. Office of Civil Defense, Hurri- that, "The biggest lesson of of Documents, U.S. Government Carla was that Printing Office; Washington, D.C. :,

fense against ,or recovery from n-uclear phasis on a given function may appropri- attack? The answer is both simple and ately vary from level to level. logical. - ! 13.35 The cases which have 'been docu-' PLANNING-RESPONSIBILITY RESTS ON- mented above all serve as illustrations of a GOVERNMENT AT ALL LEVELS single, vital truth. Namely, planning con- 13.38At the community or urban level, sists of a two-pronged approach to a poten- detailed and current radiological intelli- tial problem area which can be summa- gence would be essential for warning and rized as: directing the protective action to be taken by the local populace as-well as for control 1. LOGICAL ASSUMPTIONS of radiation exposure to personnel per- 2. PRACTICAL ANSWERS forming locally 'directed emergency and This is no less the case for radiological recovery functions as called for in the defense planning than for any other type. complete 'Civil Preparedness plan. The sole purpose-is:if the preceding para- 13.39 At the higher levels of govern- graphs has been to "set the stage" along ment, there is increasing responsibility for these lines for our consideration ofplanning, coordinating, and, as necessary, RADEF planning which will follow. directing protective, remedial and recovery actions, and brograms beyond the ca- RADIOLOGICAL DEFENSE PLANNING pabilities of the individual communities. In order to -perform such ,RADEF func- 13.36In the previous Chapter, we took of tions within the framework of the overall a level-by-level look at the operations plan, the State, county or:local level needs the RADEF organization from the basic areawide intelligence which is dependent Monitoring station on up to_ the_Sta,te upon reliable monitoring and reporting. emergencyoperating Center. We will follow this same procedure in this chapter 13.40Each State has the major respon- but, first, -some general comments on sibility for planning, development and im- RADEF planning are in order. -plementation of Civil Preparedness programs, and intrastate administration of Federal assistance for development of WHERE DOES PLANNING ORIGINATE? 'emergency operation capabilities at local 13.37 Though there is obviously a need to State levels. for careful planning in RADEF, most peo- 13.41Although the State plan need not ble are aware that, this does not mean present complete detail of all purely local these plans can be finalized in Washington radiological defense operations, local capa- and shipped out to the States and local .bility is a prime requisite for successful communities to adopt and put into effect. statewide operations and must be pro: On the contrary, with a country. as diverse vided for as a part of the 'more basic State as the United States, a plan worked tout plan. Having a State plan is, alone, just for,Chicago, or New York will not be !the not enough. ! same, indeed -should not be the same, as a plan 'devised for a farm community or a NOTE seacoast area. An understanding of the Don't forget: The primaty responsibil- wide diversity of the United States is be- ity for Civil Preparedness planning, and therefore RADE F, rests with the hind the establishment of a Federal sys- primary legal authority for whatever tem of government by the Founding Fath- government unit is involved. ers. They knew that differing situations required different, methods. This is allo 13.42Once again, planning ithe responsibility of the Coorxlinator of Ciyil Pre- true in RADEF, for at the various levels of --. government, state; county arirlocaCsome paredness at each )evel. In 'large or com- radiological defense functions are similar, plex jurisdictions; a special pranning some are materially different and the em- groupmight be established to assist the . 1-,fl 172 director in making the plan.This special hard look at realitymay be doomed to face group should :work with him (or his dep.= disaster. uty). The members of sucha group generally should be relieved from all, ,13.46 Anyone could Aroducea plan, for or many. example to counter the Texas City of their other duties to givemajor time disas and attention to planning. ter now that it is history. The realtrick would have been to planfor it before it NOTE happened as was done in South Amboy.

When authenticated by theproper offi- NOTE cial, acting within the legal purviewof his, authority, the Civil Preparedness Remember, the, difference between operational plan bears the full forceof emergency and castastrophe is plan- law. ning! 13.43Remember, a sound planning cyc. cle is a continuous planningcycle. There MONITORING STATION PLANNING, are excellent reasons for this. 13.47If Mr. Jones, newly appointed RADEF Officer for the town of Anywhere, NO PLAN WILL EVER BE COMPLETEOR U?S.A., were to address himselfto the FINAL question of planning for the monitoring network which he feels isnecessary to 13.44 Many wars have been lost be- support his radiological defense effort, the cause generals learned their lessons too logical starting point might wellbe, taken well and formed their plans too firmly.The as the determination, in view of popula- lessons they learned weie from thepre- tion and 'geography, of the totalnumber-of vious war. They analyzed the tactics, they ,radiological monitoringstations he will re- studied the success and defeats, the ad- quire. This may be logical but it isalso vances and retreats. They wouldnever wrong!-' The Correct starting pointwould make those mistakes.And'they never did. be a careful perusal .of RADEFplans al- They made new mistake's because,. while ready in existence for hiscity ok his coun- learning their lessons, and building plans try or eiren his State. ori the basis of thoselessons, the world 13.48 Every State has was 'changing. New methods were appear- an emergency operations plan already inexistence. Some ing. Thus, the French army in WorldWar plans are better than others and, I, learning well the lessons of the previous logically, some RADEF anneXes to these plansare Franco-Prussian War, deterrnined to at- more complete than others. But, inany tack, attack, always attack. Unfortn- event, before Mr. Jones doesany planning, nately, the introduction of machineguns, he should check tosee howm4ch planning barbed wire, heavy artillery, and othe,r. has already been done. If new weapons gave the advantage to the he disagrees with the plan, he has justdiscovered his defense. When the pride ofFrance broke real starting, point forbuilding up, a against the German defense's in Alsaee- ADEF capabilityfor the town. of Any- Lorraine, the war then passed intota where, U.S.A.: phase dictated not by.old Rlans but bynew 13.49 But suppose, for-thesake of argu- weapons. Thousands of lives were lost to ment, Mr. Jones found gaibia few yards of soil. Any lessons based a well-conceived RADEF annex to hisexisting area- Civil, on the early phase of World War I would Preparedness plin, equally have been incorrect during World one which spelled out' requirements, locations, numbersof moni- War II, for the tank, self-propelled artil- tors and so forth in 'complete ler*, and parachute troopsgave the initia- and correct tive once again to the attack. detail.,Suppose, further that heinherited a going monitor instructionprogram, had , 13.45- Yesterday's plans,often do not fit all -the equipment' he reqUired-and had a today's, problemst, and those who willnot long waiting list of peoplebegging him for lift their eyes from the plans to takea a chance to be radiological Monitors. Give

173 3 "ij 9

him his full quotft of monitoring stIons;so.13.54Yes, it does, but only if Mr. Jones all with ,e Ootection factor of 100 plus wants ,to ignore the potential need for twoway radios a'r well as telephones.,perforrning tasks outside shelters. We can -Would it be possible for him to still have a be reasonably sure he won't, though, be- monitoring station problem in the midst of cause he recognizes there is more to moni-

all this plenty? . ,tering than just _taking readings and. re- 13.50 The answer, of course, is yes. He_porting them. We can rest assured that would have a very- definite problem in=au-r_Vz_ Jones will see to it that his plan spite of.all the RADEF assists spelled out proyiggsfor adeqUate and continuous dis- ebove if he could npt point to at least one Onfination of such important instruction. more plus feature, that of a functionin prograni of instrument maintenan ,re- EMERGENCY OPERATING CENTER pair ahd calibration. His other e viable, PLANNING ' RADEF assets would not countr' much in an emergency if only, say % of his LOCAL AREA1 mouitoring equipment could be .either op- 13.55 By the time he began to review or erated or relied upon. prepare the portion of the local planwhich deals with his ,own EOG, Mr. Joas had learned quite a few lessons about nUMTv- SHELTER MONITORING PLANNING ing anything to chance. He aPproached 13.51knywhere, U.S.A., has a suffi- this task carefully and thoughtfully, mak- cient number of .public shelters and the ing certain, first pf all; that the ,selected most marginarprotection factor in any one facility was adequate both from the stand- of them is at least ,100. Adequiate equip- point of sufficient space as wells suffi- ment is available and already in Place in cient space for thedisplay of RADIIF data. each shelter to permit it to perform its 13.56Further, he made sure t at there selflprotecting monitoring function. Mr. would beprovision F'or an adeque staff of Jones was pleased when he learned_ this, plotters and analysts aswell as communi- buf he was doubly pleased when he also cation personnel. When he realized that learned that there was no personnel- re- these people had t9 be trained, provided quirement,for monitors, every shelter had with forms, penciI4 paper, pencil sharpe- its full quota. Now, perhaps, lie can move ners, food, water, etc., etc., he began to to one of his other RADEF prOblem areas? worry about the.size of the job which faced 13.52If he does-move away from shelz him as RADEF Officer. ter Monitoring at this point, he could be 13.57 One night he sat bolt upriglit in Making a very big mistake. The availabil- bed with the shocked -.realization that al- ity of a- faellity, the required equipment though he had taken care Of all of theie and the personnel to operate it are all many items in his EOC planning, he did .essential ingredients fo a RADEFcapabil- not know the protection' factor of the ity, true enough, but they are not suffi- building which would house the center! Cient to guarantee it. A fourth teeter is 13.58 He had, he realized, just taken require4, an all-iMportantlactor,'and that , the appearance of the building at its face value and assumed that% its protection fee" 13.53 ut let's say that Mr. Jones in- tor would be satisfactory. He recognized vestigates and finds that his local plan the ,enorrnity of his mistake immediately calls for a systematic series of field exer- and lost no time the next day before ask- cises on a {egular basis. One exercise se- ing and learning that the protection factor ries hasp just concluded and every single was more than adequate (much to his re- monitor passed with flying colors. They lief). demonstrated a firm grdsp of reporting 13.5g But he did not recegnize his real iequirements. Surely, this would indicate mistake until it was pointed out by his that training is maintained at an ade- wife when he told her what had happened, quate leyel. or rather, what could have happened._ 174 11 fl:f3 "G'eorge," she said, "it's simple. Youneed into a-series of sm-all suburbancommuni: an assistant and that's all there 4. to-itr tiesreach with its-own little-EOC: She was right, of course, because George 13..63'In-explairiing- hissituation to Jones had made avery human mistake, George Jones, he ruefully acknowledged one which is not confined to the ;tanks ofthat all initial planning had been Radiological Defense Officers qther. based on He the concept of a daytimeemergency and ,had simply failed to notice thepoint at for many months which he was "spreadinghiniself no one:tied though)t tG ex- too thin" amine the county RADEF setupin terms' and his RADEF plan encompassedmore area than one man could handle. of how it would functton inthe evening hours. He went on to pointout that the 13.60While in the State capitalon a mistake had been uncovered,interestingly business trip, George Jones dropped inon enough, throdgh the reappraisal ofappar- the State 'i,adiological Defense Officerto ently inadequate means.of alerting.certain rentW aCquaintance and in -the key operating,personnelduringthe eve- course of their conversation told him how, ning hours. This had led, inturn, to the °well Fred Green, thenew Assistantinteresting discovery thata surprising RADEF Officer for Anywhere, U.S.A.,was number of his volunteers hadaccepted working Out in the job. He mentioned the equivalent assignments intheir own home series of events which had led to theap- communities, some of whichweEe as far as pointment and was intrigued to hear the twenty-eight miles away from thecounty expression, "unmanageable span ofcon- seat: The County Coor\dinatoracknowl- trol," doe& in reference to his probl, edged that all of these people hadadvised. . . 13.61It was in exceptionally his office of their decisitaiand, -further,\ apt de- that his office 'had complete' records ofi scription, he concluded as-he drovehothe these facts. When his that evening, and:this set,himto thinking secretary had cas- in terms of the-span of control ually mentioned that t,hey seemedto be in of his, own for a rough time ifan emergency should local RADEF organization. Hehad dis-ever start in the evening, though, he Sud- cussed "span of control" (althoughnot in such a precise term) sufficiently denly realized that his, finedaytime with Fred RADEF organization would be ,Green to assure hiMself thatit -did not a desper- Tepresepla problem to their Giganization. ately overworked gf itever had. to s he turnpd into his driveviay, however,-commence functioning during the night. he was ,struck by the suddenthought that, 13.64 AS he worked with GeorgeJones this comfortable situation mightnot .be on the neW plans which calledfor several truce of the County Emergency Operating of the newer local EOC'sto report to the center to which his organizationreported. Anywhere, U.S.A., Area EinergencyOper- He dedded to look into thematter furtherEifing Center ratherthan to the County at hiaearliest opportunity. EOC, the phraseducethe span of control to .manageaFJle props)rtions,"was 13.62* Three mofithi later, the AnY-heard over and ov again becatiee it is -- Wheke, U.S.A., Emergency OperatingCen- such an apt expressin of the purpose of ter was duly entered in theState Civil an area -E0C. I to Defense Plan and all other supportingdoc- 13.65 George Joes realized, that the timats. George's suspicion had provedto 'wOrk he had done with the CountyCoordi- be 'correct, something that the County nator would be extremely worthwhilefor Civil Preriaredness COO-Mina-tor had been the county as a whole.ever though IV thinking of himself forsome time. He had meant that his own RADEF organization recogniZed,that the analysis loadthrown was\taking on a substantial a,dded respot- on his-Own RADEF Organization would sibility in receiving,.q,nalyzing,.sumrnari- '..SimPlk be_ too large to handle .if-anemer- ing and reportin&the additional data -gencY aliedlci occur during the eveningwhich the sev.u.al To* operatingcenters -10,01, a titne When the bulk of popula- yiould be sending viewed -the. tton in the c-otinty. had redistribted itself Changed situation, he kneir thathis pw9, ,

J. t personal span of controlr'rcl Fred Green's 13.69 "Just a minute!" he thought, as well had both been stretched past the "Why not use that big camera over in our danger point and something would have to County Records Section and make copies be done about it. He and Fred would have of their map for' ourselves?'1 to review their entire tables of organize- 13.70 The more.. he tliought about the tion as well as all theirIlinitial plarring idea, the better he liked it. In the first concepts. UndOubtedly, at least one mew place, there simply wasn't any be,tter map assistant would be required, perhaps even available anywhere, either in or out of the two. "One thing is certain," thought State. Second, he tidked oft, it will be Geerge; Jones, "if I have to make mistakes maintained by an outiide gariization in this RADEF work, at least I'm going to and every time a major c ange occurs, a make new mistakes!" riew set.ormaps can be produced in jUst a .13.66 The Courity..Coordihator reflected very few minutues. Third ,. he realized, it that the new plans growing out of his would be an invaluable addition to the efforts with George Jones were a big help resources of, his operations center. He de- in more ways than one. Now he had more cided to lose no time in putting his plan time to devote to an item which- he had into effect. never felt was allshould be, specifically, 13.71 When the first copies of the State the county's radiological monitoring nettHighway Department's map were deliv- work. There was a -perfectly adequate ered to his office, the County Coordinator number and distribution c't. urban monitor- lost no time in looking them over. He ing stations, true enough, brit he was not decided that the quality of reproduction comfletely satisfied with his sefup in rural was very good, that the 'maps would fill his and mobile monitoring. After all, the prob- requirement perfectly. Inspecting the lems of a county EOC could be consider- maps a little more closely, he noticed that ably more complex than those of a local the 'span of roads which would connect EOC in that county-type RADEF prob- with the new bridge to be built in a neigh- lems had to be approached from the stand- boring county were just about complete, point of area as well as population. Al-even though work hed not ybegun on though this could ,be true for a local EOCTrthe bridge itself. He was r minded of rt-- was alwayi true for a county EOC. conversation he'd had witheorge Jones a 13,67 The more Willa-ugh/ about it,the few days beforein which George had been more the CountiCoordinator was con- telling him what a boon the new bridge vinced,that a county EOC wasvractically would be. George, had mentioned that his a State EOC on a smaller scale. delivery trucks had a choice whenever 13.68 He was certain, fo'r instance, that they had a stop to make in the next the 'State Civil Preparedness organization county. They could drive ten miles upriver had n easier time with maps than he did on a road that was only fair to get to the bec use ,the Highway Department had clo qiot bridge or they could grive eighteen' 1111 downriver on a very good road land. co lete up-to-the-minute information on w e" ev road in the State, all new construe--ima e their crossover there. The ne tion, road conditions, etc., etc. As a matter Ibridge couldn't go up too soon, de far as of face, 'the-County Division Office of the orge Jones was concerned. Highway. Dep,artment (which was loeated 14.72 A sudden thought hit the Counly just down-the hall from his own'office) was ,Coordinator. _the proud.possessorbf one of those master 13.78 he never could think about Maps that the ,State used in its .highway Geo`rge Jones very much without also imaintenante and constructiorr program,,It thinking about "span of control" which was a reaLbeauty, showed,everything thatq.lways led him, in turn, to consider - anyonecotIld.possiblY.want io know about george's area' EOC and how well the plan roads in,,the State:And it was so rfuick.was working out in actual practice. _Tbe.- better, than the map* ithat!,helid Ills words, "area ,EOC" and the fact that he mobile monitors exes1. .. ju'st 'been thinking about Ilis mobile ; - 4

monitoring a few seconds beforewere the two -things that sparked his STATI EMERGENCYOPERATING CENTER idea.- He PUNNING looked at the maponce more. There it was! 13.78Slime 13.74If George! Jones' trucks had weeks later, the State Ra- to diological Defense Officer dropiesii-4non travel either ten or eighteenmiles to'cross. - the County the riv6-, why then Coordinator to see how hisnew so would the mobile Substate,E0C planningwas shIping up. monitoring teams sent out bythe County.He was, of course, particularly CooltliOTTNor of the nexteounty! interested in any RADEF developments whichmight be of use to him in his role of RADEF .13.75 "But if thearea on our side of the river were to be monitored advigor to otherOC's ;within the State.. by our Own He didn't really expect to pickup anything teams," he mused, .,"thenour neighbors so far as his own operation in the State wouldn't have to make thoselone trips just to get acrOss the river. We're' EOC was concerned because, afterall, it 'already had beef a goingconcern for at least 2 across the rier as far as theyare con- years aAd a great deal of time and talent , cerned. Whyl couldn't we take this .area had been devoted_to enáking itso. over and mimitor it for them? ifwe. did take over, our crews would 13.79 As the County Coadinatorwas be receiving showing him the only a fraction of the radiationexposure new setup, he noticed two which their crews would be 'transparent plastic panels whichhad been getting!" vertically mounted r on sturdy pairs of legs. 13.70Little did the County Coordina-The panels, were pushedback in a corner out of the way and tor, realize that his idea Would proltuce were apparently with- . the first sub-state E.,OCin his -state and, out any use that he,conkddiscoverNHe further, that his oWncounty EOC. woVd inquired about them. beconie it! He coulsee thebasic reason- 13:80"Oh,, that's my own, personallit- ing behind themove, however, once it had tle brairr-child," said theCounty Coordina:- been explained to hinibecause, after all; tor, "and I Ton% mind tellingyou I'm sort; ;Ale

1 8 1 1.77 as well is add any other information ONE FINAL WORD which IA might need in a graphic form. Of course there are many ways to display the 13.83Noi operations plan, however data and this only represents one way." sound in concept and complete in detail, is of much value if it is untested or untried. 13.82"Say, now," exclaimed the State, The readiness posture of a plan is meas- RADEF Officer, "this is really something: ured by its ability to be implemented. As a matter of fact, I think I might even Therefore, each operational plan should be become the" first ofpcial thief of your idea subjected to one or more tests as, a part of because it strikes me as a refinetnent the planning cycle. Plan tests should be worth introducing into our State EOC! made as realistic as possible, and.each test You can appreciate how much I need such should be evaluated by dualified observers a system if you need it to control a piece of as well a's by the participants. Following the total area that. I have to wOrry about. the test, an evaluation report 'shoul4 be It just goes to show that no plan is ever made. The report and-evaluation shouliol be really final and that includes first of all, used as the basis for revision and the start our own State Plan." of a new p1an2ing cycle.

1 r)

, CHAPTER 14

"PAPER PLANNING" OR REAL RADEF?

To implement the RADEF plan, ofRADEF planning and aneffective course, a variety of elements is required. RADEF organization. There are four of It is necessary to have equipment anda them. facility in which to store anduse it that much certainly is obvious. Further, the EQUIPMENTFACILITIESPERSONNEL-- equipment and the facility cannot do much TRAINING by themselves, putting them touse takes We will examine these four itemin people, sometimes a rather large number sequence in this chapter. As we do sb, it of people, to say nothing ofmoney. And, would be well to remember that these finally, these people must havesome idea requirements do not come from inspira- of what they are to door else the equip- tions or viSions. They come, instead,as a, ment will remain inert and the facility will result of t1 le. planning process which is, in be without purpose. This is just anotherturn, a two-step pr-ocdure.' way of saying that RADEF personnel need training.: 14.3To repeat our summary of these But what should come first, where is the two steps, the first consists of the estab- starting point? How can lishment of some reasonable, sensible, you tell when you well-thought-out, practical assumptions. Haves:balanced RADEF team? How doyou The second step is,qne of meeting these maintain a RADEF capabilityonce it is es, tablished? And so forth. a.skumptions with reasonable, s'ensible, The objective_of this chapter, then, is to well-thought-out, practical answers. put these various essentials ofan effective 'EQUIPMENT- -RADEF plan into- their peoper-ierspective ... to demonstrate what is necessary to 14.4In considering Me question ofra- breathe life into a paper plan and turn it diological instruments and equipment, it into an honest-to-goodness RADEFcapa- immediately begomes apparent thatone of bility. the first que,itions to be answered is, "what kind and how much?"as well as; INTRODUCTION "`where can we get it?" 14.5 To answer the last question first, 14.1 We saw in Chapter 13 that planning the Defense Civil Preparedness Agency can spell the differeiwe between an emer- has made radiological equipment available genCy which is 'promptly dealt withon a to the States through their duly consti- systematic basiS and, on the other hand, tuted Civil Preparedness organizations. an utter catastrophe. We saw that plan- This is a "through official channels"type ning guides us to the bestuse of'all availa- of exercise and thereforea detailed pres- ble resources, and, ultimately4. helpssave entation of .the fifty different channels is lives.- We saw that effective planningre- obvibusly outside the scope of this discus- quires organized, equipped, trainedper- sion. sonnel as an essential ingredient. We be- 14.6Although a detailed answer to the gan to see.that all this requires money. first question in paragraph 14.4 is even ,w 14.2 Now we are ready to break this further outside our scope, it is neverthe- planning ingredient down into itsessen- less possible to demonstrate an important tial 'parts. 'These are the basjc tools of point abont RADEF planning in offeringa 179 , 183 'comment on it. Specifically, the answerity for his local EOC. He must also have- should lie in your own plan or its RADEF radiological monitoring for community annex and, if it does not, then that plan is shelters under close control. While some of drastically in need of additional work!, these community 6.1-ielters might presum- Thtfael that such an- goswer ably be a part of his regular monitoringS. should be found in an existing plan also network in addition to their missiiin of highlig4ts another 'feature of planning. RADEF protection for the shelter, others The elements of a plan are interdependent will not. But in any event he will be re- and interrelated if the plan is a goodone, sponsible for the, adequacy of the 'facility and further, if any one of these elements insofar as it coricerns atiy aspect of should change or alter in anrway, such a RADEF. change should .be the signal for a reap- 14.12Protection factor is, of course, of praisal and possible revrsion of the plan. paramount imprtance in determining the 14.8In considering equipment require- suitability of a RADEF facility and this is ments for a Particular radio!ogical defense another area for which the RADEF Offi- area, it is important to remeMber that this cer is responsibe. He must assure himself does not merely mean operational equip- that each facility ,which has been mapped ment but, in addition, includes training in as a part of the RADEF operation hasa equipment. In this regard, an individual sufficient protection fdctor. In addition to resOnsible for a -DCPA Training Source protection factor, an important-feature of__ Set must. hold a Byproduct Material such facilities will be their ability to fit User's Certificate from his respective into the local communications plan. In .State.. And here, incidentally, is further other words, each facility which is selected proptof the interaction of ostensiblysepa- and added td the overall RADEF network rate-elements in the RADEF plan. must be capable of carrying out itsts- 14.9 Not only is the RADEF Officer re- signed function while simultaneouslyper- sponsible for obtaining the required opera- forming the vttal task of self-protection. tional equipment and makingsure that 14,13 Before leaving the question of fa- sufficient training equipm.ene is available, cilities, a word on arrangements foremer- he is also responsible f9r maintenance. To gency food and w,ater-for monitoring per- this.,ebd-r-a-"chief qnonitor" 'slibuld bap- 4-01inel would be iorder. POinted for each monitoring station.Fur- 14.14Food and W-ater stocks, it could be ther, supplementary instruitents miglit be claimed, Are not reallNt a part of the consid- reasonably required and it is up to theeration of a facility:It could be argued RADEll' Officer to determine if this isthe equally well that food and Ni,raterare cer- case as well as to prepare the necessary tainly not radiological "equipment". The justification to obtain theni. point is, however, no matter what label is placed' upon these two commoditjes, human beings cannot exist or function very long without either one. Thus it behooves 14.10If a RADEF plan is to be capable the RADEF Officer to make certain that of executIon,' there must a sufficient his facilities have adequate stoc4 of these nuniber of radiological monitoring stationS items. and communications over which they can make their reports. The RADEF Officer is PERSONNEL responsible for converting a numberon a 14.15 One of the largest contributing piece of paper (the localarea RADEF factors to RADEF personnel requirements plan) into a real monitoring and reporting is found in the radiological monitoring net- network. work. 14,11Since this monitoring and report- 14.16 Once again, the particular local ing network, will not be worth much with- Civil Preparedness plan or its RADEFan- out a place to receive such reports, this nex should provide the explicit answer to- leads the IRADEF Officer next to the facil- thiS question and, if it does not, the prob- 100 1 S'4 (;}

lem is not one .of the monitoring network andoother facilities which have but rather one of conIpletingthe plan first. an Jul-e- quate protection factor, appropriateper- Although the finalanswer to this question sonn0 who are normally,, rau,st remaina local one to be based employed at upon these facilities representanothq excel- population, industrialdistribution, geog- lent source of monitors. raphy and the like, thereare, nevertheless, certain criteria 14..19In rural and suburban arek's which can be used. where a home shelter Federal and Stategovernments period,L may have been 'des- cally issue guidelineson the number of ignated as a part of themonitoring and monitoring stations needed reporting system, membersof the family in rural and who will occupy the shelter urban areas. This informationshould be should, if pos- considered only as sible, be recruitedas a part of the,RADEF a starting point in eval- organization. uating 'the RADEFinonitdring network requirements because finalanswers will 14.20 Once again,since a I4rge cadre of always deperldupon the individualities of monitors will be needed, theselection of the particular localarea in question. personnel for training shouldbe fairly NOTE broad. Remember that'women;as Nell as men, can perform a very significant role in Do you think in terms ofso many men for this job, so monitoring, and certainly shouldnot be many men foothat one, overlooked in any recruitment-effort. or'so many_inen in he...goe,.and-so forth? 17-You do, then.. 14:21 -Tor deionTathiriatiOn fiaining,selection of key personnel shouldbe primar- STOP RIGHT NOW! ily among the fire, sanitation,rublic.works there are millions dfintelligent, sin- and'engineering services. HoWever,se1ec7, cere, 'capable women inour country. tion should also be extended:t6those per- - There are undoubtedlythousands .in sonnel who operate streetsweeping- and your own RADEF area. Besure that flushing equiprnent, roadgrad,ers, scrap- you remember this in 'yourplanning ers, and earth moving and personnelrecruitment activi- .` tand:demolition ties!!! equipment.,"Selection cli,-sicaieyperson- nel will be froni Stateriounty; 14.17, As a general rule,RADIEF. per,- and sOnnel should be selected prirharily pal dmployer;,but'shotilTalsobesxteriaa fronf..to, others. óh 'as* higlwdy State and local governmenteipployees. construction This will provide all the contractors,- since riinSt. of theequipment advantages oft.needed for decOnfamination _working on tlfe basia ofan existing orgarill' work will be zational frainework. Formonitors, it isfound in these areas tosay nothing'of_a suggested that, firemen, State-highwtiy_pai,.ready, source of personneltrained in its trqlmen, highway 'maintenancepersrinel, their auxi4ries and their reserves"bese- TRAINING lected for training. Furthe'f,radiation. monitoring should be included,as-apa'rt of 14.22 There are two basicareas of ehe basic training for all,new recruits in training, the training ofmonitors and the these services and refreshermonitor training of the'RADEF staff.Tbe latter is training should be routinelyscheduled, fpr of particular importance forit is impera- all pergonnel. To supplementthis initiVl tive that the leadership staffbe provided cadre of Monitors; 'high schooland college in order to forma seed-bed for providing science teachers, selectedState, county,'further training to otherpersonnel. and municipal employeesin the engineering, sanitation, welfare,'dnd health serv- RADEF,OFFICER AND RADIOLOGICAL ices could alsO be selected-for monitor training. MONITORING.FOR INSTRUCTORS TRAINING 14.18 In areas where monitoring sta- 14.23Local and .State jurisdietions tions have been Rstablislied in iiidustrial have the responsibility plants, hospitals, commercial byildings for obtaining trained Radiological DefenseOfficers.

'-1 85 1 81 Upon completion of his training, the determine how many monitors we need. To RADEF Officer provides instruption to the do this it is necesiary to analyze the local people who have been selected for his RADEF plan since training requirements RADEF staff andsthe monitors needed in will stem from the assessment contained his comthunity. . in the plan. (If no plan is available,mone 14.24 B&sure you don't overlook the should be developed first.) resource represented by the capabilities existent in the Armed Forces tb supplement' monitor training resources. 14.25 As .monitprs are trained, the RECRUITMENT OF RADEF PERSONNEL RADEF Officer should assign them to a specific monitoring station for operaltbnal 14.80After we have found how many purposes. Generally, mOnitors should be trained personnel are needed, it will be assigned to facilities which are near where' necessary to recruit the manpower for they normally work ocieside. Each moni- training. By far the best sources will be tor will-be ordered to report to his desig- full-time municipal, county and State em- nated shelter or monitoring station in an ployees. Since they are also one of the best emergency. All monitors should be in- sources for Civil Preparedness pe'rsonnel structed to find some, shelter in the event other than RADEF, coordination will be they -cannot, reach their assigned station.'necessary to avoid conflicting assign- In addition, provision must be made, for ments. Another possible difficulty is that, the families of, morlitors, both as a morktle RADEF activities have no exact counter-, ,factor and also by way of avoiding-possible parti-n--existink _governments, In bthef, confusion during an emergency.- words-, the Civil Preparedness plan which 14.26 Upon completion of- his -training,'fits the police fcirce'into the law and order' each monitor will be furnished a HAND- role Or the sanitation department into the BQOK FOR RADIOLOGICAL MONI- decontamination role during ,an emer- TORS,4.9 containing detailed in- gency will not find a ready-made govern- strtfitions tor Monitoring and reporting mental activity whibh-fits RADEF activi- operation( as well as special' instructions ties. ,c9.11:MIlipg his responsibilities for dealing NOTE with rotitine and emergency radiation conditions. DCPA will provide these manuals It is imporiant, both for motivation for distribution to the monitors. and realism in training, that the stu- 14.27 Continuing' training of monitors dent have aeassignment based on the RADEF plan BEFORE he beginti to provide for personnel attrition and re- to undergq training., fresher training of monitors on an annual to 6 months basis should be- arranged.. for- py the lochl RADEF Officer. 14.28 The following paragraphs provide TRiINING LOCATION a summary of some important points for.' persons concerned with establishing- 14.31The courses shopld be taught in RADEF training programs, either for ra- locations convenient for tbtdent diological mOnitors or for the RADEF since many will presumably be volunteers, staff. it is doubly important that all impedi- S. ments to training, such as disfant plaies TRAINING REQUIREMENTS and inflexible or inconvenient class hourg, be removed. If On-the-job traiping can be, arranged 'with local government authorit'., 14.29. The first step is to'find out what ties,. this will materiallir aid in the rapid we need in the way of training. We must training-pfonnitors and others. ,

Is? \ A TRAINING LOGISTICS end in themselves. Incidentally, one of the 14.32It ,is important that training most important things to do when using equipment be ordered at the earliestmo- such 'equipment is to check It out in ad- ment after training requirementsare de- vance; be sure it works, and that you kri\ow howto use it. termined, and that thenecessary user per- s mits needed for handling TrainingSource Sets be applied for. The Defense Civil Pre- TRAINING EVALUATION paredness Agency providesa "Radiologi- cal Monitoring Training Package," K-24 14.35It is'important that there be fre- which includes an Instructor Guide, and quent tests of skills learned in the training supporting visual aid material. This, too, courses. Such evaluation should be on pro- should be obtained'without delay and in ficiencythrough demonstrationrather sufficient quantity. than student reproduction of academic or theoretical knowledge. Make. it realistic should be the guide .to effective training TRAINING ASSISTANCE and evaluation Of such training. 14.33It is vital that liaison be established with .all agencies, public and pri- NOTE The best things in life may be free, but Arate,,that can offer assistance in teaching building and training a RADEF or- or recruitment. Whatever instructor capa-- ganization is not! At any level of gov- bilities already exist on the local level ernment, there is a requiremvnt of should be ap-praised and utilized. Find out budgeting for RADEF. DON'T FOR- from the already existing Civil Prepared- GET,,T0- PUT RADEF IN THE ness organization what iT availab.-Other BU_D ET! cities' in your :arealmay haie.a. fully functioning organization witha number of A BIRD'S-EYE-VIEW OF RADEF qualified instructors. There's no advan- 14.36It's no secret to anyone who has tage in '"going it alone" so, if youcan get had any contact with radiological defense help from outside your immediate jurisdic- that, as a subject, it is technical and it is tion, don't hesitate to take it. After all, complex. Although a single individualas- fallout will not recognize any boundaries. signment can be presented in a relatively simple, straightforward manner, the sum TRAINING METHODS of all such assignments covers a very wide range of knowledge and presents a rather 14.34 As we have seen,we are noticomplicated picture. trainingjust for training's sake norare we training to increase theoretical 14.37 This situation leads us to a single or aca- simple question, "Who will tie all these demic knowledge. We ckre training forspe- cific jobs. Hence, the selection of loose ends to'gether?". We have radiologi- course cal instruments, monitoring stations, shel- conteit material should aim at: ter radiological requirements, training tr ining to do a particular job source sets, data to be pldtted, curves to be training to initill degirable habits drawn, reports to be received, reports to training to enhance operational knowl- be sent, the list is literally endless and yet edge some sort of knowledgeable coordination To achieve these ends, course materiar4must take place between all these facets should stress student participation. Pas- and elements and bits and pieces. sive lecture methods'should be avoided in 14.38 For the sake of argument, let's favor' ols the active approach featuring consider what would be necessary if we demonstration, exercises, laboratory, and were to decide to go into a manufacturing queStion and ansWer methods. Teaching business. Let's for example, make it furni- aids, models, slides, films, vugrephs, flan- ture manufacturing. Immediately Yip real- nel boards, And ôt1Wr visual aids should be ize that we need someone who knows Sed when they support learningas an something about building furniture. This

1)143 leads us to a conclusion that he should RADEF OFFICERS.ARE MADE, NOT BORN! also know something about the wood and othqr materials which will be required, 14.41There is no such thing as being wheie to find them and how to Use them..appointed an expert on any given subjea He must be aware of the availability and and radiological defense is no different uses of a whole variety of special tools. from any other subject in this regard. The And he must know a great deal more as only road to becoming a Radiological De- well. We are aware of how foolish we fense Officer is study and tiaining. would be to hire cabinet makers, salesmen, 14.42 But what about Joe Smith who clerks, and so forth until we were certain has just received his doctoratok in, of all we had our man who knew the furniture things, nuclear.physics? Can't we at least manufacturing business. This example is recognize him as a Radiological Defense so obvious it's almost ridiculous, isn't it? Officer because of his provable knowledge 14.39But it is not ridiculoUs when the of atomic structure, fission, radiation, cur- radiological defense parallel is drawn be- ies and, things like that? cause it is surprisingly easy to become 14.43No, we cannot recognize Doctor bogged down in the many technical consid- Joe Smith, nuclear physicist, as a Radiol- erations of RADEF work and, as a result, ogical Defense Officer unless he has been lose sight of a basic fact. That fact is: \ trained as a Radiological Defense Officer. Monitors, facilities, instructors, hi- 14.44 The point may seeni Obvious but struments, communications,,,decon- it is -nevertheless very well taken. Cer- tamination teams, RADEF plans-and tainly there is nothing wrong with' having all the rest of it do not-constitute a RADEF Officer who is also a nuclear a physicist, no more so than there is any- radiological defense capability... thing wrong with having one who is a sci- unless... ence instructor, industrial scientist, or an RADIOLOGICAL DEFENSE OFFICERS engineer, but none of these individuals will are available to tie the paqkage to- be a RADEF Officer until he has actually gether into the real countermeasure been trained as such. .------ror survival that RADEF is meant to be. 14.45. Along the-se general lines, it is a Just as most other facts can be ex- good idea to- remember that the DCPA pressed in corollary terms, this one courses which lead up to qualifying as a can be given such expression wiA itADpF Officer have been developed witha equal ease. The corollary is: view toward proxiding the technical infor- Provided that there are sufficient mation-which will be required to do the job. The individual _is, of course, expected to RADIOLOGICAL DEFENSEOFFICE4 carry out a certain amount of independent available, a radiological defensecape- study as well as keep himself up to date on bilitY is in process of building, regardless of inadequacies in any other the subject tIvough continuing elose RADEF area. contact via the channels 9f his own Civil Preparedness organization. 14.40 These facts can be expresse&on a national scale as well as a purely local one. Our national RADEF capability requires facilities, monitors, instruments and many other elements of survival in the nuclear IMPORTANT age ... and must include a cadre of capa- Our nation ne-eds thousands of capable, trained RADEF Officers... In- ble, trained Radiological Defense Officers. strutters can and will provide the With such a group, we can have a national training... the individual, however, RADEF capability but without it, never. must provide the capability!. GLOSSARY .

GLOSSARY

A , ATOMIC WEIGHT: The relative weight of ABSORBED DOSE:see DOSE, an atom of the given element. As a basis of reference, the atomic weight of the AFTERWINDS: Whld currents setup in common isotope of carbon (carbon 12) is the vicinity of a nuclear explosion di- taken to be exactly 12; .the atomic rected toward the burst center, result- weight of hydrogen (the lightestele- ing from the updraft accompanying the ment) is then 1.008. Hence, the atomic rise of the fireball. weight of any element is approximately AIR BURST: The explosion ofa nuclear the weight of an atom of that element weapon at such a height that the ex- relative to the weight of a hydrogen panding fireball does not touch the atom. earth's surface when the luminosity isa AVALANCHE EFFECT: 'The multiplica- maximum (in the second pulse). tive process in which a single charged .ALPHA PARTICLE: A particle emitted particle accelerated by a strong electric spontaneously from the nuclei of some field produces additional charged parti- radioactive elements. It is identical with cles through collision with neutral gas , a helium nucleus, having a mass of four molecules. This cumulative increase of units and an electric charge of two pogi- ions is also known as Townsend ioniza- tive units. See Radioactivity. tion or a l'ownsend avalanche. Ava- .--lanche occurs in the Geiger tube of.a CL- AMBIENT: Going or moving around; also V-70 Or.' enclosing encompassing. ATOM: The smallest (or ultimate) particle of an element that still retains the characteristics of that element. Every atom BACKGROUND RADIATION: Nuclear (or consistS of a positively charged central ionizing) radiations arising from within nucleus, which carries nearly all the the body and from the surrodndings to mass of the atom, surrounded by a num- which individuals are always ,exposed. ber of negatively charged electrons, soi The main sources of the natural back- that the whole system is electrically/ ground radiation are potassium-40 in- neutral. See Element, Electron, Nucleus.- the body, pbtassiurn-40 and thorium, uranium, and their decay prodOcts (in- ATOM/C. BOMB (OR WEAPON): Aterm cluding radium) present in rocks, and sometimes applied to a nuclear weapon cosmic rays., utilizing fission energy only. See F'is- sion, Nuclear Weapon. BARRIER SHIELDING: Shielding gained by intirposing a physical barrier be- ATOMIC CLOUD: See Radioactive Cloud, tween! a given point and radiation ATOMIC NUMBER: See Nucleus. source. I BETA PARTICLE: A charged particle of fery small mass emitted spontaneously

1 When possible, definitions have been reprinted from the glossary of from the nuclei br certain radioactive The Effects of Nuclear Weapons, February 1964. elements. Most (if not all) -Of the direct 189 1 $S fission proOucls emit Jnejkative) beta erally ejected from the atom. Another particles. Physically, the beta particle is (secondary) photon, with less energy, identical with an electron moving at -then movea-off in new direvtiont an high _yeloeity. gee Electron, rission angle to -the direction of motion of the Products, Radioactivity: . primary photon. INDING ENERGY: The tremendous en- CONTAINED UNDERGROUND BURST: . ergy which holds the neutrons and pro- An underground detonation at sucha tons of an atomic nucleus together. depth that none of the radioactive resi- BIOLOGICAL DOSE: See Dose. dues escape through the surface of the ground. BLAST WAVE: A pulse of air in which the presure increases sharply at the fronts CONTAMINATION: The deposit of radio- accompanied by winds, pro5agated con- °active material on the surfaces of struc- tinuously from an explosion. See Shock tures, areas, objects, or,personnel, following a nuclear explosion. This mate- Wave. rial generally consists of fallout in BODY BURDEN: The amount of radioac- which fissionproducts and other tive material in the body at a given weapon debris have become ,incorpo- time. rated with particles of dirt, etc: Contam- ination can also arise from the radioactivity induced in certain substances by CALJBAATIONDeterminationf varia"- the action of neutrons .from a. nuclear. - tion in accuracy of radiological instru- ex6losion. See Decontamination, Fal- ments, Radioactive sources are used to lout, Induced Radioactivity, Weapon De: produce kr..2Awn exposure rates at speci- bris. fied distances. The variation in accuracy of a radiological instrument can be de- CONTAMINATION CONTROL.; Action to termined by comparing it with these prevent the spread of fallout and reduce known exposure rates. contamination of people, areas, equipment, food and water. -CHAIN RE-ACtiTION.,. When qa 'fissionable nucleus is split bx a ,peuVon it releaseS COSMIC RAYS: Very high energy particUr- T energy_ anaone or more neutrons; These late (particles) ahc electroma°gnetit -' in turn split more fissionable-nuclei re- (rays) radiations whi h originate out in leasing more energy and neutrons, thus sp,Ace and constantly bombard the m*aking the process a self-sustaining earth. chain reaction. CRITICAL MASS: The minimum mass 'Of CHROMOSOME: One ofthelparticles intO a fissionable material; that.will just yvhich a portion of the celfnucleus splits maintain a _fission chain reaction under Up prior to cell division: assuined to be precisely specifieii Conditions, such as determinants of species and of sex. . the nature' of the material and its pu- rity, the nature and- thickness of the 'CLEAN WEA150N: One in which meas- tamper (or4neutron reflector), the den- ures have been taken to reduce the sity (or compression), and the physica

_ amount of residual radioactivity rela- shape (or geometry). For an explosion t tive to a "normalr weapon of the same occur, the systern must be supercritic ° energy Yield.- 0,r< i.t., the mass tf material must excea COMPTON EFFECT: The scattering ol the critical mass under the existing photons (of gamMa or X-rd'ys) by the conditions. See Supercritical. . orbital electrons of atoms. In a'collision-CUME (Ci): A unit pf radioactivity; it is between a (primary) photon and an elec: the quantity of any radioactive species. tron, some of the energy of the photon is in Which 3.700 x 10nuclear disintegra- transferred to the electron. which is gen- tions occur, persecond. The GAMMA CURIE is sometimes definedcorre- DOSE ': A (total or accumulated) quantity ,spondingly as the quantity of material of ionizing (or nuclear) radiation. The in which this number ofgamma-ray pho- term dose can be used in the -sense of tons are emitted per seCond. the exposure dose, wypressed in roent- CYCLOTRON: An appavatus which ob- gens, which is, a masure of the total- ' tains high-energy electrically- charged amount of ionization that' the quantity particles by whirling them atimmense of radiation could produce in air. Thisl speOs in a strong magnetic field; used should be distingnished from the ab- especially to create 'artificial radioactiv- sorbed doee, given in reps or rads, which ity; an atom smasher. represent the energy absorbed from the -radiation per gram of specified body tissue. Further, the biological dose, in rem's, is a measure of the biological effectiveness of the radiation exposure. See RAD, REM, REP, Roentgen. DAUGHTER PRODUCT: Theproduct (dif- DOSE RATE ,As a general rule, the fexent element) formed whena radioac- amount of ionizing (or nuclear) radia- tive material decays. Someradioactive don to which are individual would be elements will formmany daughter prod- exposed or which. he would receive per' . ucts during their decaii to a stablestate. unit of time. It is, usually expressedas DECAY (OR RADIOACTIVEDECAY): roentgens, rads, or rems per hoLfror in The decrease in activity ofany xadioac- multiples or submultiples Of these units, tive material with thepassage of time, .such as ! milliroentgens per hour. The due to the spontaneous emissionfrom dose rate is commonly, used to. indicate the atomic nuclei of either alphaor beta the level of radioactivity ina contaminated area. particles, sometimes accompaniedby . gamma radiation. See Half-Life, Radio- DOSIMETER: An instrument formeasur- activi ing and registering total accumulated` DECONTAMINATION: The' reductibi;or exposure to ionizing radiations. . removal of contaminating radioactive'DRAG LOADING: The-forceon an object. . material from a structure,area, object, or structure due to the transient winds1 for persen. Decontaminationmay be ac- accompanying .the passage ofa blast cothplished by1(1). treating thesurface so wave. The drag pressure is the product, as to remove Or decrease the contamina- of the dynamic pressure and the drag tion:, (2) letting the material standso coefficient which is dependentupon the that -the radioactivity is decreasedas a shape (or geometry) of the structureor result of nat ral decay; and (3)covering object. See Dynamic Pressure. the contami ation. DYNAMIC PRESSURE: The airpressure DEUTERIUM: Ati isotope ofhydrogen of which results from the.mass air flow (or mass 2 Units; it is sometimes referred to wind) behind the shock front ofblast as heavy hydrogen. It Can be used in wave. It is equal tO4the product of half thermonuclear fusion reactions for_the the density of the air through which the release of energy. Deuterium-isex- blast wave passes and thesquare of the tracted from water which alwayscon- particle (or wind) velocity behind the tains 1 atom Of deuterium to about6,500 shock front as it impingeson the object -atoms of.ordinary (light) hydrogen.See or structure. Fusion, Thermonuclear. DIRTY WEAPON: One whichproduces a "In this revised text,"exposure" and "exposurerate" have been sub- . larger *amount of radioactive residues stituted for "dose and "dose rate"in those instances where the Meas. than a "nOrmal" weapon of the urement is explicitly or implied in roentgen units. pose and doserate have been retained where the meaning is an absorbed quantityor rite yield. in rad or rem units..

187 9

1 E EPIDERMTS: The outer-skin. EARLY FALLOUT:-See !hal lout. EPILATIdN: Loss of hair. ELECTROMAGNETIC PULSE (EMP)4 ERG; A unit Of energy or w'iork. An erg is Energy radiated 'by a nuclear detona-' the energy required for,an electron to tion in the- meditnn-to-low frequelncy ionize about 20 billion molecules of air. range that maKaffect or damage e14ctri7 cal orelectronic compOnents and equip- ERYTHEMA:_ A_superficial skin disease ment. Chafacterized by abnormal redness, but without swelling orfever. gLECTROMAGNtTIC RADIATION: A traveling wave motion resulting from,'EXCITATION: The raising or transfer- , oscillating magnetic and electric fields. ring of an atom from its normal energy Familiar electromagnetic radiations leirel to a higher energy level. range from X-rays (and gamma rays) of EXPOSURE CONTROL: Procedures short wavelength, through the .ultravi- taken to keep radiation exposures of olet, yisible, and infrared regions, to ra- individuals or groups from exceeding a dar and radio waves of relatively long. recommended level, such as keeping out- wavelength. All electromagnetic radia- side missions as short as possible. tions travel in a vacuum with the velocity of light. See Photon. EXPOSURE: SeeDose. , ELECTRON: A particle of 'very small EXPOSURE RATE: SeeD6se Bate. mass, carrying a unit negative or posi- tile charge. Negative electrons, stir- ., rounding the nucleus; are present in all atoms; their number is equal to the FALLOUT: The process or phenomenon of number of positive charges (or protons) the fallback to the, earth's surfzice of in the particular nucleus. The term elec- particles contaminated with radioactive ! tron, where used alone, Commonly refers material from the radioaitive cloud. The to these negative electrons. A positive term is also applied in a collective sense electron is usually,called a positron, and to the contaminated particulate matter a negative electron is sometimes called itself. The early (or local) fallout is de-. a negatron. See Beta Partcle. . fined, somewhat arbitrarily, as those particles which reach' the earth within ELECTRON VOLT (eV): The energy im- 24 hours after a nuclear explosion. The parted to an electron when ,it is moved delayed (or worldwide) fallout consistS of ,through a potential difference of 1 volt. the smaller particles which ascend into -It is equivalent to 1.6 x 10-12 erg: the upper trOposphere and into the ELEMENT: One of the distinct, basic vari- stratosphere and are carriefl by winds to eties of matter occuring in nature all parts of 'the earth. Th e! delayed fal- which, individually or in combination, kilt is brought to earth; mainly by rain compose substances of all kinds. APprox- and snow, over extended periods rang- imately ninety different elements are ing from months to years. known to exist in nature and several FALLOUT MC'',NITORING STATION: others, including plutonium, have been deSignated facility for the collection of obtained as a result of nticlear reactions radiological data by trained and assigned with these elements. monitors using' instruments Stored or EMERGENCY OPERATING CENTER assigned to that location. It should have (EOC): The protected site from which, good fallout protection and relatively civil governm'ent officials exercise direc-' reliable cOmm'unications. Examples don and-cot-OA in an ergency. Might be a fire station, police or public -workh buildini, public fallout shelter, ENERGY:'Capaeity for p rforming work. etc. 111,11 I a? ,

FILM BADGE: A small Metalor plastic forming additional(daughter) products, frame, in the form ofa *badge, worn- by with the result that the confplex mix-' personnel, ay containing X-ray(or sim- ture of fission productsso formed con- ilar photographic) film for esthnating ,tains about 200 different isotopes'of 36 the total amount of ionizing(or nuclear) elements.. radiation to which an individual ,has been exposed. FLASH BURN: A burn caused by eices- sive exposure (of bare skin)to thermal FIREBALL: The luminous sphereof hot, radiation. See Thermal Radiation. gases which form a few millionths ofa second after a nuclear explosionas the FRAdTIONATION:Any one of seveial result of 'the absorption by thesur- processeshapart from radioactive decay; rounding meditim of the`thermal X-rays which results in change in, the comi:sosi- emitted by the eXtremely hot (several ton of thd radioactive weapon debris. tens of millions degrees) weapon resi- As a result bf fractionation, the delayed dues. The exterior sof the fireball in air is fallout generally' contains relatively initially sharply defined by the lumi- more of strontium 90 and cesium 137, nous shock front and later by,the limhs which have gaseousprecursors, than of the hot gases themselves (radiation does the early fallout froma surface, front). burst. FIRE STORM: Stationarymass fire, gen- FREE AIR OVERPRESSURE (ORFREE erally in built-up urbanareas, generato FIELD OVERPRESSURE): Theunre- ing 'strong, inrushink winds from all.si- flected pressure, in excess of theazr e. des;, the winds keep the fires from bient atmosphericpressure, created in spreading while adding fresh oxygen the,air by the, blastwave from an explo- to ftion. increase their intensity. s FISSION: The process' wherebythe nu- FUSION: The process wherebythe nuclei cleus .of a particular heavy element of light elements, especially those of the .splits into (generally) two nuclei of Asotopes of hydrogen, namely, deuterium lighter elements, with the releaseof and tritium, combine to form thenu- substantial amounts ofenergy. the cleus of a hiavier element with the. re- most important fissionable materials lease of substantial amounts ofenergy. are uranium 235 a/nd plutonium 239. See Thermonuclear. FISSION FRACTION: The fraction(or percentage) of the total yield ofa nu- G clear weapon which is due to fission. For GAMMA RAYS (OR RADIATIONS): Elec- thermonuclear weapons the average tromagnetic radiations of highenergy value of the fission fraction is about50 originating ip atomic nuclei and pery.ertt. accom- , panying many nuclear teactions,e.g., FISSIONPRODUCTS: A general termnit, fissibn, radioactivity, andneutron,cap- the complex mixture of substancespro- ture,. Physically, gamma raysare identi- duced as a result of nuclear fission. A cal with X-rays of highenergy, the only distinction should be made between Vssential difference being thatthe X- these and the direct, fission productsor rays do not originate frorp atomic nuclei, fission fragments whichare formed by but areProduced in otherways, e.g., by the actual splitting of the heavy-ele- slowing down (fast) electrons of htgh ment nuclei. Something like 80 different energy. 'See Electromagnetic Radiation, fission fragments result from roughly 40. X-Rays., different modes of fission ofa given 4GEIGER COUNTER:An electrical device nuclear species, e.g., Uranium 235or plu- which can be used tordetecting and tonium 239. The fission fragments, being meastiring relatively low levels ofnu, s radioactive, immediately begin to decay, clear radiation. ID3 189 t GENETIC EFFECT: The effect (of nuclear taming fluorine, chlorin4, broMine, ,io- radiation, in particular) 'of producing dine and astatine. changes (nutations) in the hereditary HEAVY HYDROGEN: Se, Deuterium. components (genes) in the germ Cells present in'the reproductive organs (gon- HEAVY WATER:,Water containing heavy ads). A mutant gene causes changes in hydrogen (deuterium) atoms in place .of the next generation which may or may the 6rmal hydrogen..atoms. , not be apparent. HIGH-ALTITUDE BURST: This is de- GEOMTRY SHIELDING: Shielding fined, 'somewhat arbitrarily, as a deto: gained by distance from the source of nation at an, altitudes over 100,000 feet. radiation. ' Above this level the distribution of the energy, orthe explosion between 'blast GRAM: A unit of mass.and weight in the and thermal radiation changes appreci- metric system equal to approximately 'ably with incyeasing altitude dupe to one-thirtieth of an ounce. changes in the fireball phenomena. GROUM) ZERO: The point on the surface HOT SPOT: Region in a contaminated of land qr water vertically below or area in' which the level ot. radioactive above thelcenter of a burst of a nuclear contamination is somewhat greater (or atomic) weapon; frequently abbrevi- than in neighboring regions in the area. ated to GZ. For a buTst over or under See Contamination. water, the term surface zero should HYDROGEN BOMB (OR WEAPON): A preferablybe term sometimes applied to nuclear GUN-TYPE WEAPON: A device in which weapons in which part of the explosive two or more pieces uf fissionable mate- energy is obtained from nuclear fusion rial, each less than a critical mass, are (or thermonuclear) reactions. See F'u- brought together very rapidly so as to sion, Nuclear Weapon, Thermonuclear. form a supercritical mass which can ex- plode as the result of a rapidly expand- ing fission chain. IMPLOSION WEAPON: A device in which H a quantity of fissionable material, less 0 than a critical mass, h-as its volume sud-% HA,LF-LIFE: The .time required for the denly decresed by compression, so that activity qf a given .radioactive si;ecies to it becomes supercritical and an explo- 'decrease to hajf of its initial value due. sion can take plabe. The compression is to radioactive decay. The half-life is a achieved by means of a spherical ar- characteristic property of aach radioac- rangement of specially fabricated i tire species and is independent of its shapes of ordinary high explosive which' amount or condition. The effective half- produce an inwardly directed implosion life of a given isotOpe is the time in wave, the fissionable material being at which the quantity in. the body will de- the center of the sphere. See Supercriti- radioac- ease to half as a result of both cal. ye ded'ay and biologicalelimination. INDUCED RADIOACTIVITY: Radioactiv- HALF-VALUE THI,CKNESS: The thick- ity produced in ceftain materials as a ness of a given material which will ab- result of nuclear reactions, particularly sorb half the gamma radiation incident the capture of neutrons, which are ac- upon it. This thickness depends on the companied by the formation of unstable nature, of the materialit is roughly (radioactive) nuclei. The activity in- inversery proportional to its density duced by 'neutrons from a nuclear (or and also on the energy of the gamma atomic) explosion in materials dontain- rays. 'Mg the elements sodium, manganese, HALOGEN: The family of elements con- silicon, or aluminum may be significet. 190, 104 INFRARED: Electromagnetic radiations separation occurs. In the senSe2used in 4 of wavelength between the longe$t visi- this book; ionization referrespecialiyto ble* red (7,000 Angstroms-or 7 x 1024., the removal of an electron (negative millimeter) and about 1 miliiineter. See charge) from the atorri or molecule, glectromagneticRadiation. either directly or, indirectly, leavinga INITIAL NUCLEAR RADIATIOn: NU- positively charger ion.The separated , clear radiation (essentially neutrons electron and ion are referred toas an and gamma rays) emitted from the fire- ion pbair. See Ionizing Radiatilon. - ball and the cloud column during the ION'PAIR: See loniiation. first minute af ,. er a nuclear (or atomic) explosion. The 'rn' limit ofone minute IONIZING RAMATION: Electromagnetic is set, somewharbitrarily, as that r.e- radiation (gamma raysor X-rays) ar quired for thesource of part of the ra- particulate radiation (alpha particleS, diations (fission products, ,e'tc., in the beta particles, neutrons, etc.) capableor radioactive cloud) to attain sucha producing ions, i.e., electrically charged height that only insignificant amounts p-articles, directly or indirectly, in its reach the earth's surface. See Residual passage through matter. , Nuclear Radiation. ISOCROME: A lin,e corinectingthose INTENSITY: The energyletany radia- points on die earth at which fallout tion) incident upon (or flowing through) from anyone weapon is forecastto unit area, perpendicular to the radiation reach the surface/let thesame time. beam, in.unit time. The intensity of ISOTOPES: Forms Of thesame element thernial radiation is generally expresse4 hiving identical chemicalproperties but in calories per square centimeter pei differing in their atomicmasses (due to second falling on a given surface at any , different numbers of neutrons in their ,N.;specified,instant. As applied to fluclear respective nuclei) aris in their ntplear radiation, the term intensity issome- properties, e.g., radioactivity, fission, ' times used, rather loosely, toexpress etc. For example, hydrogen hasthree the exposure rate at 'a given location, isetopes, with mdsses of 1 (hydrogen),'2 e.g, in roentgeris.(or milliroentgens) per (deuteriuM), and 3-(tritium) units, reypec- hour. tivelYe. The first two ofthese are stable INTERNAL RADIATION: Nuclear radia2 (nonradioadi4W, but thethird (tritium) tion (aiTha and beta Partias and is a riviioactive isotope. Both ol thecorn-. gamma radiatiOn) resulting fro/ft radio- mon isotOpes of urantum; with Masses Df _active substances in t)-ie body. Impor: 235 and 238 units, respectively,are-ra-, tant sources are iodine 131 in the thy- dioactive, emitting alpha particles,but roid glanfieand strontit0 90 and pluton- their' half-lives'are different. Further- ium 239 in the bone, more, uranium 2.135 is fissionable by neu$ trons of all eneggies, but uranium 238 INVERSE SQUARE LAW: The law which will unArgo fisOt n only with nearons 4 States that when radiation (thermAl'or of high energy, See Nucleus. 'nuclear) from a point' source is emitted uniformly in all directions, the amount J. reCeived per unit area atany given dis- 0 (None) tance from the source, assumingno ahr $ sorption,4s.linversely proportional to the K square orthat distance.. KILO-ELECTRON VOLT (keV):An amount Of energy equar to 1,000,electron I , IONIZATION: The separation of.a nor-- mally electrically neutral atomor mole- volts. See Electron Volt. cule into electrically charged compb- KILOTON ENERGY (KT): Theenergy of a nents. The term is Also employed to de- nuclear (or atomic) explosion which is scribe,the degree or extent to which this equivalent to that produced by theex-

191 . plosion of 1 kiloton (i.e., 1,000 tons) of MICROCURIE: A one-millionthipart 'of a. TNT, i.e., 16'2 calories of 4.2 34110'6 ergs. curie. See Curie. See Megaton Energy, TNT Equtivalent. 4 MICRON: A one-millionth pa-a-I:of a-meter, i.e., 10-6 meter or.10-4 centimeter; it is 1. roughly four one-hundred-thousandths LD/50 or LD-50 or LD50: Abbreviations for (4 x10-6) of an inch. median lethal dOse. See Medic:M. Lethal Dose. MICROSgCOND: A one-millionth part of a second. MILLICURIE (mCi): A one-thousandth MACH EFFECT: See Mach Stem. part of a curie. MACH STEM: The shock fr,ont formed by MILLIREM: A one-thousandth part of a the fuSiori of the incident and reflected shock' fronts from an explosion. The rem. term is generally used with reference to 'MILLIROENTGEN (mR): A one-thou- a blast wave, propagated in the air, re- sandth,part of a roentgen. flected at the surface of the earth. The MILLISECOND: A one-thousandth part Mach stem is hearly perpendicular to the reflecting surface and presents a of a second. slightly convex (forward) front. The MITOSIS: The process by which living yeah stem is also called the Mach front. cells multiply in the pody by splitting or

MALAISE: Uneasiness. Discomfort. 4 MOLECULE: The smallest unit of a chem- MASS: A measure of the quantity of mat- ical compound. For example a molecule ter. The material equivalent of energy. . of water consists of two hydrogen atoms Mass and energy are different forms of combin,ed with one atom,.of oxygen thg same thing. (H20), and a 'molecule of sugar contsists ,MASS NUMBE-R: See Nitbleus.. of a combination of twelve carbon at- MED,IANLETHAL DOSE: The ampunt of oms, twenty-two hydrogen atoms, and iqpizing (or nuclear) radiation exposuie 4e1even oxygen atoms (C,2H2201). over, the whole body which, it is ei- MONITOR: An individual trained to meas- pected, ygothd be fatal to 50 percent of X ure, record, and report radiation expo- large group of living creatures or orga- sure and 'exposure rates; provide limited ''nisms. ft is commonl* (although not uni- field guidance on radiation hazards as- versally) accepted that about 450 roent- sociated with operations to which he is gens, received over the whole body in assigned; and perform operator's main- the course of a few' days or less, is the tenance of radiological instruments. median letWal dose for human beings. MONITORING: The procedure or opera- MEGACURI,E: ,One million curies. See tion of locating and measuriAg radioac- Curie. tive contamination by means of survey MEGATON ENERGY (MT): The energy, inkruments which carfdetect and meas- of a nuclear explosion which is equiva- ure ionizing radiations. The individual lent to 1,000,000 tons (or 1,600 kilo-tops) performing theoperation is calleda, of TNT, i.e.,10'6 calories or 4.2 x 1022 egs. monitor.. See TNT Equivalent. ** MI'JTATION: A change in thestharacteris: MEV (MeV): Million electron volts, a unit tics of an organism produced by altering of ,energy Rommonly used, in nuclear the,usual hereditary pattern..Radiation physics. It is equivalent to 1.6 x10-6 erg. can cause mutations in altliving things. A,pproxiinately 200 MeV of energy are produced for every nucleus that under- sN goes fission. See Electrov..Volt. NEGATIVE PHASE: See Shock Wave.

- 1 (Ay-, 192 t. NEUTRON: A neutral particle, i.e., with NUCLEUS (OR ATOMIC NUCLEUS):The no electrical charge, of approximately small, central, positively charged unit mais, present in all atomic region nuclei, of an atom which carriesessentially all except those of ordinary (light)hydro- the mass. Except for the nucleus gen. Neutrons are required to initiate of ordinary (light) hydrogen, which isa single the fission process, and' largenumbers of neutrons are produced by proton, all atomic nuclei contain both both fission protons and neutrons. The numberof ....., and fusion reactions in nuclearexplosions. protons determines the totalpositive 4 charge, or atomic number; thisis the NUCLEAR FISSION:See Fission. same for all the atomic nuclei ofa given chemical element: The totalnumber of NUCLEAR.RADIATION:'rarticulateand neutron's and protons, calledthe mass electromagnetic radiation emittedfrom number, is closely relatedto the mass atomic nuclei in various nuclearproc- (or weight) of the atom. Thenuclei of esses. The importanVnuclear radiations, isotopes of a given element containthe from the weapons 4andpoint,are alpha same number of protons, but different and beta ,partiOles,gamma rays, and numbers of _neutrons. Theythus have neutrons. All nuclear radiationsare ion- the same atomic number, andso are the izing radiations, but thereverse is not same element, but they have different true; X-rays, for example,are included mass numbers (and masses). Tfienu- among ionizing radiations, but.theyare clear properties, e.g., 'radioactivity,fis- not nuclear radiations since they donot sion) neutron capture,etc., of an isotope originate from atomic nuclei.. SeeIoniz- of a given. elementare, determined by ing Radiation, X-Rays. both the number ofneutrons and the number of protons. See Atom,Flement, NUCLEAR REACTOR: An,apparatus in Isotope, Neutron, Proton. which nuclear fission is sustainedin a regulated self-supporting chainreaction. NUDET: Repori of nucleardetonation. . 'NUCLEAR WEAPON (OR BOMB):A general name given to anyweapon in which 0 the explosion results fromthe energy ORGAN: Organizedgroup of tissue having released by reactions involvingatomic one or more definite functions toper- nuclei, either fissionor fusion or both. form in a living body. Thus, the A- (or atomic) bomband the H- (or hydrogen) bombare both nuclear OUTSIDE/INSIDE RATIO (OD:The weapons. It would be equally true to call measured rati6 of the falloutgamma thetn 4atomicweapons, since it is the radiation exposure rate atsome point energy of atomic nuclei that is involved outside a shelter to theexposure rate at in each case. However, ithas 'become some point inside the shelter. For radiol- more-or-less customary, althoughit is ogical defenae purpose's, thespecific out- not, strictly accurate, to referto weap- side point selected shouldhave minimal ons in which all the energy results from protection. (See Protection Factor.) fission as A-bombsor atomid bombs. In OVERPRESSURE: The transientpres- order to hiake a distinction, thoseweap- sure, usually expressedin pounds per ons in which part, atdeast, of theenergy square inch, exceeding the ambjent iesults from thermonuclear(fusion) re- pressure, manifested in the shock (or actions among the isotopes ofhydrogen blast) wave froman explosion. The vari- have been called. H-bombsor hydro'gen ation of the overpressurewith time de- bombs. pends on theenergy yield of the explosion, the distance fromthe point of NUCLEON: Thecommon name for a con- burst, and the medium -in stituent particle ofa nucleus such .as a which the proton or neutron. weapon is detonated. The peakoverpres- sure is the maximum value of theover- 197 193 * pressure at a given location arid is gen- transport and store radioactive mate- erally experienced at the instant the riaI;. The thick walls protect the person shock (or blast) viave reaches that loca- handling the container from nuclear ration. See Shock Wave. diatia PLUTONIUM: (Chemical symbol Pu.) A Manmadetransuraniumelement, PAIR PRODUCTION: Theprocess atomic number 94. When uranium 238 is whereby a gamtna-ray (or X-ray) pho- bombarded with neutrons in an atomic ton, with energy in, excess of 1.02 MeV. reactor some of the uranium is con- in passing near the nucleus of an atom verted by nuclear reactions into pluton- is converted into a positive electron and ium, a fissionable material. a negative elctron. As a result, the photon ceases to exist. See Photon. POINT SOURCE: A point at which radioactivity is concentrated as,opposed to an PEAK OVERPRESSURE: The maximum area over which radioactive material overpressure value at the blast front. might be spread. The DCPA Training PERIODIC TABLE: A chaFt showing the rSource Set sealed capsule is an e9mple arrangement of chemical elements in of a point source. order of increasing atomic number in POSITRON: Positively charged electron. addition to grouping according to certain chemical similarities. 'POSITIVE PHAS: See Shock Wave. PERSONNEL *EXPOSURE MEASURE- PROTECTION FACTPR (PF): The ratio of MENTS: The measured exposure re- gamma radiation exposa-e at a Stand- ceived by shelter occupants and opera- ard Unprotected Location to exposure tions personnel in the field. at a protected location, such as a fallout sh'elter. The Standaid Unprotected Lo- PHOTOELECTRIC EFFECT: The process cation is defined as a point 3 feet above whereby a gamma-ray (or X-ray) pho- an infinite, smooth, ground plane unifor- ton, with energy somewhat greater than mally covered with fallout. Protection that of the binding energy of an electron factor is a calculated %alue suitable for in an atom, transfers all its energy to planning purposes as an indicator of the electron which 'is consequently re- relative protection. (See Outside/Inside moved from the atom. Since it has lost Ratio.) all,its energy, the photon ceases to exist. See Photon. PROTON: A' particle of mass (approximately) unity carrying a unit positive PHOTON: A unit or "particle" of electrom- charge; it is identical physically with agnetic radiation, possessing a quantum the nucleus of the ordinary (light) hy- of energy which is characteristic of the drogen atom. All atomic nuclei contain particular radiation. If v is the fre- protons. See Nucleus. quency of the radiation in cycles per second and X is the wave length in centimeters, the energy quantum of the photon in ergs is hv or hcX where h is (None) Planck's constant, 6.62 x 10" erg-second and cis -the velocity of light (3.00 x 1010 centimeters per second). For gamma rays, the photon energy is us- RAD: A unit of absorbed dose of radiation; ually expressed in million electron volt it represents the absorption of 100 ergs (MeV) units, i.e., 1.24 x 10'°X where X is of nuclear- (or ionizing) radiation per in centimeters or 1.24< 10-2/X if X is in gram of the absorbing material or tis- Angstroins. sue, PIG: A container (usually lead) used to RADEF: Radiological Defense.

194 d'3 RADIOACTIVE CLOUD: An dll-inclusive is thus defined, in general,as the dose of term for the mixture of hotgases, any ionizing radiation which results in smoke, dust, and, other particulatemat- the absorption of about 97 ergs ofen- ter from the weapon itself and fromthe ergy per gram of soft tissue. For soft environment, which is carried aloft in tissue, the rep and the radare essen- conjunction With the rising fireballpro- tially the same, See RAD, Roentgen. duced by the detonation ofa nuclear weapon. RESIDUAL NUCLEAR RADIATION: Nuclear radiation, chiefly beta particles RADIOACTIVITY: Thespontaneous dis- and gamma rays, which persists for._ integration of unstable nuclei withthe some time following a nuclear (or resulting emission of nuclear radiation. atomic) explosion. The radiation is emit- RADIATION EXPOSURERECORD: The ted mainly by the fission products and card issued to individuals forrecording other bomb residues in the fallout, and their personal radiationexposures. to some extent by earth and watarcon- stituents, and other matgrials, in which RADIATION INJURY: The harmfulef- radioactivity has been i*duced by the fects caused by ionizing radiation. capture of neutrons. See Fallout, In- RADIOLOGICAL DEFENSE: The duced Radioactivity, fnitial Nuclear Ra- organ- diation. ized effort, through warning,detection, and preventive and remedialmeasures, ROENTGEN (R): A unit ofexposure to to minimize Ur effect of nuclearradia- gamma (or X-) radiation. It is defined tion on peoplerandresources. precisely as the quantity of gamma (or RBE (RELATIVE BIOLOGICALEFFEC- X-) radiation such that the associated corpuscular emission per 0.001293 TIVENESS): The ratio of the numberof gram rads of gamma radiition ofa certain of air produces, in air, ions carryingone energy which will produce a specified electrostatic unit quantity of electricity of either sign. From the accepted value biological effect to the number ofrads of another radiation required to produce (34 electron volts) for the energy lost by the same effect is the RBE ofthis latter an .electron in producing a positive-neg- radiation. ative ion pair in air, it is estimated that 1 roentgen of gamma (or X-) radiation, REM: A unit of biological ,dose of radia- would result ,in the -absorption of about tion; the name s derived from the initial 87 ergs of energy per gram of air. letters of the term "roentgen equivalent man (or mammal)." See RAD. SAP REMEDIAL MOVEMENT: Movement of SHELTER: A habitable"structureor space people postattack toa less contami- stocked with essential provisions and nated area or a .better protected loca- used to protect its occupants from'fal, tion. lout TadiatiOn. REP: A unit of absorbed dose of radiation 'SHIEEDING: Any material o'robstruction now being replaced by the rad; the name which absorbs radiation and thustends rep is derived from the initial letters of to protedt personnelor materials from the term "roentgen equivalent physi- the effects of a nucleai- explosion.A cal." Basically, the rep was intendes) to moderately thick layer ofany opaque express the amount ,of energy absorbed material will provide satisfaltory shield- per gram of soft tiswe is a result of ing from thermal radiation,but a con- exposure to 1 roentgen of gamma (or X-), siderable thickness of material of high raidation. This is estimated to be abgut density may be needed for nuclearra- 97 ergs,- although the actual Value de- diation shielding. pends on certain experimental diiia SHOCK WAVE:,A continuously, pro,pa- which are not precisely known. Therep . gated pressure pulse (or wave) in the

41, 195 i or / surrounding medium which may be air, clouds of water never form and there is practically no convection. See Tropo- water, or earth, initiated by the expan- _ sion of the hot gases produced in an pause, Troposphere. .... , explosion. A showave in air is gener- SUBCRITICAL: The inability of a fission'- ally referred to asblast wave, because able maferial to support a self-sustained it resembles and is accompanied by chain reaction. strong, but trfnsient, winds. The duration of a shock (or blast) wave is distin- SUBSURFACE BURST: tee Underground guished by two phases. First there is the Burst, Underwater Burst. positive (occompression) phase during SUPERCRITICAL:, A term used to de- , which the pressure rises verY sharply to scribe the state of a given fission system a value that is higher than ambient and when the quantity of fissionable mate- 'then decreases rapidly to- the ambient rial is greater than the criqcal mass pressup. The Positisq phase for the dy- ' under, the existing colidilions. A 'highly namic pressure is somewhat lonOr thak supercritical system is essential for the for overkes,sure, due to the manentum production of energy at a very rapid of the moving air behind the shock . rate so that an explosion may occur. See. front. The duration of the positive phase Critical Mass. increase's and the maximum (peak) pressure decreases with increasing distance SURFACE BURST: The explosion of a from an,explosion of given energy yield. nuclear (or atomic) weapon, at the sur-, -- In thp second phase, the negative (or face of the land or water or at a height suction) phase, the pressure falls below above the surface less than the radius of ambient and then rpturns to the am- the fireball at maximum luminosity (in bient value. The duration of the nega- thesecond thermal pulse). An explosion tive phase, is approximatelY constant in which the weapon is detonated ac- throughout the blast wave history and tually on the surfaq (or within 5W" may be several times the duration of the feet, where W is the explosion yield in positive phase. Deviations from the am- kilotons, above or below the surface) is bient pressure during the negative called a contact surface burst or a true, phase are nevei large and they decrease surface burst. See Air Burst. 0 with increasing distance from the explo- SURVEY METER: A portable instrument, sion, See' Dynamic Pressure, Overpres- such as a Geiger counter or ionization sure. chamber, used to detect nuclear radia- t SOMATIC: Of/or relating to the body, as tion and to measure the exposure rate. opposed to the spirit; physical. See Monitoring. SPECT/RUM: An image, visibleor invisi- SYNDROMt, RADIATION: The complex ble, formed by rays of light or other of symptoms characterizing the disease radiant enetgy, in which parts .are ar- known as Adiation injury, resulting ranged according to their refrangibility from excessive exposure of the whole (or or wave-length, so that all of the same a large -part) of the body to ionizing. wave-length fall together while those Of radiation. The earliest of these symp- different wave-lengths are separated toms are nausea, vomiting, and diar- from each other, forniing a regular pro- rhea, which mak be followed by loss of . hair (epilation), hemmorhage; inflamma- ressive. series. thin of the mouth .and throat, and gen- STRATOSPHERE: A relatively stable I eral loss of energy. In severe cases, layer Of the atmosphere between the where the radiation exposure has been tropopause and a height of about. 30. relatively large, death may occur within miles in which the.temperature changes , two to four weeks. Those who survive 6 ,iery little (in polar and terriperate weeks' after the receipt of a Single expo- zones) ox increases (in the tropics) with sure of radiation may lenerally be ex- increasing altitudes. In the.. stratosphere pected to recover. 196 / o 2 0 0 , 4. TRANSMUTATION: Thechanging of One TAMPER: A strong container. element into another by a'nuclearreac- tion. THERMAL ENERGY: Theenergy emitted from the fireball as thermal radia- TRITIUM: A radioactive isotope of hydro- tion. The total amount of .thermalen- gen, having a. mass of 3 units; it is ergy reeeive&-per unit area at a speci- produced in nuclear reactors by theac- fied distance from a nuclear (or atomic) tion of neutronson lithium nuclei. explosion is generally expressed., in TROPOPAUSE: The terms of calories per square centimeter. . . imaginary.baundary layer dividing the stratospherefrom the See Thernzql Radiatidn. f , lower part of the atmosphere,the tropo- THERMONUCLEAR: An9adjective refer- sphere. The tropopause normallyoccurs ring to the procdss (or' processes) in at4an altiture of about 25,000.to 45,000 which very inghtemperatures are used feet in polar and temperatezones, and to bring about the fusion of light nuclei, at 55,000 feet in the tropics. such as those-ef the hydrogen igotopes TROPOSPHERE: The regionof the atmbs- (deuterium and tritium), with the.ac- phere immediately abovethe earth's conyanying liberation 'ofenergy. A stirface and up to the thermonuclear bomb is a weapon in tropopause in .11 which the temperature falls fairly'regu- which part of the explosionenergy re- larly with increasing altitude, sults .from 'thermonuclear fusion clouds reac- form, convection is active, and mixingis tions. The high temperatures requird- continuous and more or less complete. are obtained by means of a fission explosion. See Fusion. U re'L , THERNIAL RADIATION: Electromag- ULTRAVIOLET: Electromagneticradia- netic radiation emitted s(in two pulses tion of wave length between the short- from an air burst) from the fireballas a est visible violet and soft X-rays. consequence of its very high temperature; it consists essentially of ultravi- UNDERGROUND BURST: The exp'losion- olet, visible, and infrared radiation's.In of _a nuclear weapon with its center the eariy stages (first pulse ofan air more than 5W" teet, where W is the burst), when the temperature of the explosion yields hi kilotons, beneaththe fireball is extremely high, the ultravi- surfac,e of the ground. -SeeContained olet radiation predominatein t.he see-, Underground Bturst. ond pulse, the temperaturesare- lower UNliERWATER The explosion of and mast of the thermal radiation lies ih a nuclear weaponith its center be- the visible and infrared regions of the neath the sUrface of the water. spectrum. From a high-altitude burst, the thermal radiation' is emitted ina UkANIUM: (Chemicalsymbol U.) The' single short pulse. heaviest naturally.occurrini radiciactive element, atomic number' 92. The only TNT EQUIVALENT: Ameasure of ihe , appreciable souroe of fissionablemate- 'energy released in the detonationof a , rial occurring in naturkis inuranium nuclear weapon, or in the explosion ofa ore. This contains aboul 0.7% of the given quantity of fissionable material, fissionable isotope Um and 99.3%of the expressed in terms of the weight of TNT nonfissionable isotope U238. which would release thesame amount of energy when exploded: The TNT equiva- V lent is usually stated in kilotonsor me- (N o n'e) gato s. The basis. of-the TNT equiva- leflc# is that the explosion of 1 ton of W TN releases 109 calories ofenergy. See WEIGHT: A measuye of the force with Kilotori, Megaton, Yield. which matter is attracted to the earth. 44)1 197 ... J.

^ MVORLDWIDE FALLOUT:See Fallout. Y

- X YIELD (OR ENERGY YIELD): The total effective energyJeleased in a miclear X-RAYS: Electromagnetic radiations;of explosion.. It is usually' expressed in , . _high energy having wave lengths terms of-the equivalent tonnage-of TNT aiorter than those in are ultraviolet required to produce the same energy region,.i.e., less than 10-6 cmor 100 release in an explosion. The total energyI Angstroms. As generally produced by X- yield is manifested as nuclear radiation, ray machines, the'y are brethisstralilung thermal radiatton, and,shock ()4 blast) resulting from the interaction of elec- energy, the actual distributiOn.being de- trons of 1 kilo-electron volt or more en- pendent -upon the, medium in which go ergy with a metallic target. See gamma explosion occurs (primarily) and also Rays, Electromagnetic Radiatiop., upon the type of weapon ;and the i'ime after detonation. .

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