Chapter 2

HRHuman ResourcesTD Training & Development ¾ Radiation Protection Philosophy

¾ Sources of External Radiation

H-201 - Health Physics Technology - Slide 1 - RADIATION PROTECTION PHILOSOPHY

H-201 - Health Physics Technology - Slide 2 - Objectives

¾ Understand the bases for radiation protection standards and principles

¾ Discuss the differences in the dose limits between various groups

H-201 - Health Physics Technology - Slide 3 - Question

What is the NRC ’ s Mission Statement?

H-201 - Health Physics Technology - Slide 4 - Evolution of Radiation Protection Standards

Time Period Maximum Permissible Dose (rem/year) 1925-1931 10% of skin erythema dose (SED ~ 600 rad) 1931-1936 50 1936-1948 30 1948-1958 15 External: 5 (actually 1¼ per quarter) 1958-1994 12 (if lifetime < 5(Age-18), 3 per quarter) Internal: 5 (about 520 MPC-hrs per quarter) 1994-Today 5 (total = external + internal)

H-201 - Health Physics Technology - Slide 5 - Applying Standards

Groups Body Parts

Members of the Public Whole Body Occupationally Exposed Extremities Minors Skin Declared Pregnant Woman (Embryo/Fetus) Lenses of the Eyes

Medical Patient? Internal Organs

H-201 - Health Physics Technology - Slide 6 - Incremental Dose and Risk Level

SOURCE/LIMIT DOSE RISK Estimated, but not Natural - not Background regulated controlled Mini mal – not Exempt Quantities Small , not regulated controlled ALARA From zero to the limit Lowest Possible No deterministic, Regulatory Limit Permissible acceptable stochastic Permissible in Tolerable (per Emergency Limit Exceptional Cases volunteer)

H-201 - Health Physics Technology - Slide 7 - Ranking of Perceived Risk

League of College Business Activity/Technology Women Voters Students Executives Experts Nuclear Power 1 1 8 20 Motor Vehicles 2 5 3 1 Handguns 3 2 1 4 Smoking 4 3 4 2 Motorcycles 5 6 2 6 Alcohol 6 7 5 3 General Aviation 7 15 11 12 Police Work 8 8 7 17 Pesticides 9 4 15 8 Surgery 10 11 9 5

H-201 - Health Physics Technology - Slide 8 - Ranking of Perceived Risk

League of College Business Activity/Technology Women Voters Students Executives Experts Fire Fighting 11 10 6 18 Large Construction 12 14 13 13 Hunting 13 18 10 23 Spray Cans 14 13 23 26 Mountain Climbing 15 22 12 29 Bicycles 16 24 14 15 Commercial Aviation 17 16 18 16

Electric Power (non-nuclear) 18 19 19 9 Swimming 19 30 17 10 Contraceptives 20 9 22 11

H-201 - Health Physics Technology - Slide 9 - Ranking of Perceived Risk

League of College Business Activity/Technology Women Voters Students Executives Experts Skiing 21 25 16 30 X-Rays 22 17 24 7 Football (HS & College) 23 26 21 27 Railroads 24 23 20 19 Food Preservatives 25 12 28 14 Food Coloring 26 20 30 21 Power Mowers 27 28 25 28 Prescription Antibiotics 28 21 26 24 Home appliances 29 27 27 22 Vaccinations 30 29 29 25

H-201 - Health Physics Technology - Slide 10 -

Title 10 CFR Part 20*

Standards for Protection Against Radiation

* NRC provides assistance to States expressing interest in establishing programs to assume NRC regulatory authority under the Atomic Energy Act of 1954, as amended. Section 274 of the Act provides a statutory basis under which NRC relinquishes to the States portions of its regulatory authority to license and regulate byproduct materials (radioisotopes); source materials (uranium and thorium); and certain quantities of special nuclear materials. The mechanism for the transfer of NRC’s authority to a State is an agreement signed by the Governor of the State and the Chairman of the Commission, in accordance with section 274b of the Act.

H-201 - Health Physics Technology - Slide 12 - Agreement States

Agreement Non-Agreement Letter of States States Intent

Note: NRC maintains regulation of nuclear power plants, major fuel cycle facilities and most federal facilities (e.g. VA, Air Force, Navy) in all states. 10 CFR 20 Purpose

PURPOSE It is the purpose of the regulations in this part to CONTROL the receipt, possession, use, transfer and disposal of licensed material by any licensee in such a manner that the TOTAL DOSE to an individual ((gincluding doses from LICENSED AND UNLICENSED radioactive material and from radiation sources other than background radiation) DOES NOT EXCEED THE STANDARDS for protection against radiation prescribed in the regulations in this part. However, nothing in this part shall be construed as limiting actions that may be necessary to PROTECT HEALTH AND SAFETY.

H-201 - Health Physics Technology - Slide 14 - §20.1301 Dose limits for individual members of the public

(a) Each licensee shall conduct operations so that –

(1) The total effective dose equivalent to individual members of the public from the licensed operation does not exceed 0.1 rem (1 millisievert))y in a year, exclusive of the dose contributions from background radiation, from any medical administration the individual has received, from exposure to individuals administered radioactive material and released in accordance with §35.75, from voluntary participation in medical research programs, and from the licensee's disposal of radioactive material into sanitary sewerage in accordance with §20.2003, and (2) The dose in any unrestricted area from external sources, exclusive of the dose contributions from patients administered radioactive material and released in accordance with §35.75, does not exceed 0.002 rem (0.02 millisievert) in any one hour. H-201 - Health Physics Technology - Slide 15 - §20.1302 Compliance with dose limits for individual members of the public

(b) A licensee shall show compliance with the annual dose limit in §20.1301 by –

(1) Demonstrating by measurement or calculation that the total effective dose equivalent to the individual likel y t o recei ve th e hi gh est d ose fthlidfrom the licensed operation does not exceed the annual dose limit; or

H-201 - Health Physics Technology - Slide 16 - §20.1302 Compliance with dose limits for individual members of the public

(2) Demonstrating that –

(i) The annual average concentrations of radioactive material released in gaseous and liquid effluents at the boundary of the unrestricted area do not exceed the val ues specifi ed i n t abl e 2 of appendi x B t o PtPart 20; and (ii) If an individual were continuously present in an unrestricted area, the dose from external sources would not exceed 0.002 rem in an hour and 0.05 rem in a year.

H-201 - Health Physics Technology - Slide 17 - §20.1101 Radiation Protection Programs

(d) To implement the ALARA requirements of §20.1101 (b), and notwithstanding the requirements in §20.1301 of this part, a constraint on air emissions of radioactive material to the environment, excluding Radon-222 and its daughters, shall be established by licensees other than those subject to §50.34a , such that the individual member of the public likely to receive the highest dose will not be expected to receive a total effective dose equivalent in excess of 10 mrem per year from these emissions. If a licensee subject to this requirement exceeds this dose constraint, the licensee shall report the exceedance as provided in §20.2203 and promptly take appropriate corrective action to ensure against recurrence.

H-201 - Health Physics Technology - Slide 18 - Regulatory Definition

RESTRICTED AREA Means an area, access to which is limited by the licensee for the purpose of PROTECTING INDIVIDUALS AGAINST UNDUE RISKS from exposure to radiation and radioactive materials.

H-201 - Health Physics Technology - Slide 19 - Compliance vs. Liability

“While a nuclear utility may have some confidence that carefully following the NRC’s permissible dose limits for external and internal exposure set forth in 10 CFR Part 20 will avoid regulatory fines, no such confidence exists that the same low doses will protect a nuclear utility from being assessed huge judgments in personal injury lawsuits.

For example, a jury awarded $10.5 million to the estate of Karen Silkwood, even though her dose was only about ¼ of a maximum permissible body burden and even though she had no cancer or other demonstrated ill effect due to her radiation exposure.”

H-201 - Health Physics Technology - Slide 20 - Compliance vs. Liability

In the O’Connor v. Commonwealth Edison case*, the utility argued that the “duty owed” the employee was to limit the workers dose to less than the numerical standards that are labeled as “permissible dose” by the CFR.

The plaintiff (who had sued because of cataracts due to a 45 mrem “excessive dose”) argued that the duty owed by the utility was “to avoid excess exposure,” which he never defined, but claimed he “felt warm” while working.

The utility won. * O’Connor v Commonwealth Edison Company, 1994 H-201 - Health Physics Technology - Slide 21 - Is There Any Difference Between These Two Statements?

¾ You shall monitor adults who are likely to receive a dose in excess of 10% of the limits.

¾ You shall monitor adults who are at risk of receiving a dose in excess of 10% of the limits.

H-201 - Health Physics Technology - Slide 22 - Is There Any Difference Between These Two Statements?

¾ Each licensee shall conduct operations so that the total effective dose equivalent to individual members of the public does not exceed 0.1 rem in a year.

¾ No member of the public shall receive a dose in excess of 0.1 rem total effective annual dose equivalent.

H-201 - Health Physics Technology - Slide 23 - Question

If the biological risk of a given radiation exposure is the same for everyone, why would the limit for a dose to a member of the public be set at 2% of that for a radiation worker?

H-201 - Health Physics Technology - Slide 24 - Question

Why would a 17 year old who works in a licensees facility (e.g., hospital volunteer) be limited to 10% of the dose for an 18 year old co-worker?

H-201 - Health Physics Technology - Slide 25 - Question

Why would a 17 year old who works in a licensees facility (e.g., hospital volunteer) be permitted to receive 5 times more dose than a 17 year old who visits the facility daily (e.g., a relative of a patient) but doesn't work there?

H-201 - Health Physics Technology - Slide 26 - Question

If the biological risk of a given radiation exposure is the same for everyone, and, if the embryo/fetus of a declared pregnant woman is not a radiation worker , why would the dose limit be 10 times lower than an occupationally exposed individual BUT 5 times higher than that for a member of the public?

H-201 - Health Physics Technology - Slide 27 - Do You Know?

What is the dose limit for the embryo/fetus of an occupationally exposed pregnant woman who has NOT declared her pregnancy?

H-201 - Health Physics Technology - Slide 28 - Questions?

END OF RADIATION PROTECTION PHILOSOPHY

H-201 - Health Physics Technology - Slide 29 - SOURCES OF EXTERNAL EXPOSURE

H-201 - Health Physics Technology - Slide 30 - Objectives

¾ For Reactors, list the major categories of sources of external radiation exposure and discuss the significance of each

¾ For Materials Applications, identify the categories of radiation sources and describe the types and magnitude of the sources employed

H-201 - Health Physics Technology - Slide 31 - Sources of Radiation

Reactor Materials

Fuel Medical Fission Process Industrial Fission Products Military Activation Products Aviation Support Research Commercial

H-201 - Health Physics Technology - Slide 32 - Medical

¾ Human Use ƒ Nuclear Medicine o Diagnostic (99mTc, 131I, 153Gd, 125I, 201Tl) o Therapeutic (131I, 32P, 89Sr) ƒ Radiation Therapy o Teletherapy (60Co) o Brachytherapy (137Cs, 192Ir, 198Au, 125I, 109Pd)

¾ Non-Human Use ƒ Research (32P, 14C, 35S)

¾ In-Vitro Laboratory (125I, 51Cr, 59Co)

H-201 - Health Physics Technology - Slide 33 - Industrial

¾ Radiography (192Ir, 60Co, 137Cs)

¾ Well Logging (241Am, 137Cs, 60Co, 238U, 131I, 3H)

¾ Irradiators (60Co, 137Cs)

¾ Gauges ƒ Fixed (137Cs, 60Co, 147Pm) ƒ Portable (241Am, 137Cs)

¾ Fuel Cycle (U)

H-201 - Health Physics Technology - Slide 34 - Commercial

¾ Personal ƒ Wristwatches (3H, 147Pm) ƒ Dinnerware (U)

¾ Recreational ƒ Lantern Mantles (232Th)

¾ Safety ƒ Smoke Detectors (241Am) ƒ Warning/Exit Signs (3H) ƒ Shielding (238U)

¾ Service ƒ Anti-Static Devices (210Po)

H-201 - Health Physics Technology - Slide 35 - Aviation

¾ Operational ƒ Fixed Wing Aircraft o Oil Level Indicators (85Kr) o Aileron Counterweights (238U) o Magnesium/Nickel Skin Panels (232Th) o Spark Gaps/Igniters (60Co) ƒ Helicopter o Blade Integrity and Ice Detection Systems (90Sr)

¾ Historic Displays/Vintage Aircraft (226Ra)

¾ Safety Items ƒ Runway Lights and Markers (3H)

H-201 - Health Physics Technology - Slide 36 - Miscellaneous

¾ Support ƒ Calibration/Check Sources (60Co, 137Cs, 239Pu, 241Am, 252Cf, 238U, 90Sr, 232Th) ƒ Laboratory/NIST Standards (many α-β-γ) ¾ RhResearch ƒ Chromatographs (63Ni) ¾ Military ƒ Armor Piercing Projectiles (238U) ƒ Lensatic Compasses (3H, 147Pm) ƒ Chemical Agent Monitors (63Ni, 241Am, 3H) ¾ Education (many) H-201 - Health Physics Technology - Slide 37 - Typical Quantities

Example Special Units SI Units (37x) environmental sample picocurie 10-12 millibequerel 10-3 laboratory standard nanocurie 10-9 becquerel 100 in-vitro tracer microcurie 10-6 kilobequerel 103 nuclear medicine millicurie 10-3 megabequerel 106 calibration source curie 100 gigabequerel 109 teletherapy source kilocurie 103 terabequerel 1012 irradiator megacurie 106 petabequerel 1015

H-201 - Health Physics Technology - Slide 38 - Sealed Source Applications IAEA

H-201 - Health Physics Technology - Slide 40 - END OF SOURCES OF EXTERNAL EXPOSURE

H-201 - Health Physics Technology - Slide 41 - Questions?

END OF CHAPTER 2

H-201 - Health Physics Technology - Slide 42 -