Handbook of Operations Involving the Use of Radiation Sources
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Nuclear Threat
MANAGEMENT OF RADIOLOGIC CASUALTIES Nuclear Threat . Formerly .Soviet Union .Nuclear fallout . Now .NBC threat against civilians .Accidental exposure of workers and public Images: CIA, FBI Accidental Exposure in Brazil . Cesium-137 source found by scavengers in 1987 . Source broken open, contents shared . 112,800 surveyed for contamination . 120 externally contaminated only . 129 internally & externally contaminated . 20 required hospital treatment . 14 developed bone marrow depression . 8 treated with Granulocyte Macrophage Colony-Stimulating Factors (GM-CSF) . 4 died acute phase, hemorrhage, infection . 1 died in 1994 from liver failure Images: CIA Medical Staff Exposure Medical staff received doses: . Maximum 500 millirem (5 millisieverts) .Natural background radiation dose ~ 200 millirems annually . Average 20 millirem (0.2 millisieverts) .Equivalent to one chest X-ray Juarez, Mexico Incident . 400 curies of cobalt-60 in stainless steel therapy device sold for scrap . Ended up in recycled steel rebar . Wrong turn into Los Alamos lab . I0 people significantly exposed . 1 construction worker died .bone cancer . 109 houses demolished in Mexico Images: CIA US Experience 1944-1999 . 243 radiation accidents leading to “serious” classification . 790 people received significant exposure resulting in 30 fatalities .Incidents included: . 137 industrial . 80 medical . 11 criticality Image: DOE The Basics of Radiation Radiation is energy that comes from a source and travels through matter or space Radioactivity is the spontaneous emission of radiation: . Either directly from unstable atomic nuclei, or . As a consequence of a nuclear reaction, or . Machine – produced (X-ray) Image: NOAA Contamination . Defined as internal or external deposition of radioactive particles . Irradiation continues until source removed by washing, flushing or radioactive decay . -
Radiation Survey Meters in Hospitals: Technology, Challenges, and a New Approach
White paper Radiation survey meters in hospitals: technology, challenges, and a new approach This white paper introduces a new radiation sur- essary environmental radiation in hospitals. To vey meter for the hospital segment: the RaySafe lower the risks of unwanted radiation-induced 452. First, the need for survey meters in hospi- effects, the goal is to minimize the exposure to tal environments is described. This is followed unnecessary radiation, both for patients and staff. by an introduction to common survey meter To be able to take the correct measures, it is es- technologies to illustrate their possibilities and sential to know the properties of the radiation in delimitations. Next, some difficulties with survey terms of energy range, dose rate, type of radia- meter measurements in hospitals are identified tion, and more. This is where radiation survey and discussed. Finally, the technology inside the meters are needed. RaySafe 452 is presented to summarize how the instrument addresses the identified issues. Figure 1 illustrates some measurement scenarios and demonstrate the wide range of measurement 1. Why radiation survey meters are need- needs in hospitals. Table 1 gives an overview of ed in hospitals the main areas of application of survey meters in hospitals, with quantities, units, and typical Ionizing radiation is not visible to the human eye. energy ranges of the radiation. It does not smell or make a noise, and you cannot feel it. In the complex and busy environment of a hospital, how can you ensure that patients and staff are not exposed to more ionizing radiation than necessary? Ionizing radiation is utilized for different purposes in medical procedures, with the three main areas being diagnostic imaging, nuclear medicine, and radiotherapy. -
Dead Time and Count Loss Determination for Radiation Detection Systems in High Count Rate Applications
Scholars' Mine Doctoral Dissertations Student Theses and Dissertations Spring 2010 Dead time and count loss determination for radiation detection systems in high count rate applications Amol Patil Follow this and additional works at: https://scholarsmine.mst.edu/doctoral_dissertations Part of the Nuclear Engineering Commons Department: Nuclear Engineering and Radiation Science Recommended Citation Patil, Amol, "Dead time and count loss determination for radiation detection systems in high count rate applications" (2010). Doctoral Dissertations. 2148. https://scholarsmine.mst.edu/doctoral_dissertations/2148 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected]. DEAD TIME AND COUNT LOSS DETERMINATION FOR RADIATION DETECTION SYSTEMS IN HIGH COUNT RATE APPLICATIONS by AMOL PATIL A DISSERTATION Presented to the Faculty of the Graduate School of the MISSOURI UNIVERSITY OF SCIENCE AND TECHNOLOGY In Partial Fulfillment of the Requirements for the Degree DOCTOR OF PHILOSOPHY in NUCLEAR ENGINEERING 2010 Approved by Shoaib Usman, Advisor Arvind Kumar Gary E. Mueller Carlos H. Castano Bijaya J. Shrestha © 2010 AMOL PATIL All Rights Reserved iii PUBLICATION DISSERTATION OPTION This dissertation consists of the following two articles that have been, or will be submitted for publication as follows: Pages 4-40 are intended for submission to Journal of Radioanalytical and Nuclear Chemistry. Pages 41-62 have been published in Nuclear Technologies journal (February, 2009). iv ABSTRACT This research is focused on dead time and the subsequent count loss estimation in radiation detection systems. -
Appendix B: Recommended Procedures
Recommended Procedures Appendix B Appendix B: Recommended Procedures Appendix B provides recommended procedures for tasks frequently performed in the laboratory. These procedures outline acceptable methods for meeting radiation safety requirements. The procedures are generic in nature, allowing for the diversity of research facilities, on campus. Contamination Survey Procedures Surveys are performed to monitor for the presence of contamination. Minimum survey frequencies are specified on the radiation permit. The surveys should be sufficiently extensive to allow confidence that there is no contamination. Common places to check for contamination are: bench tops, tools and equipment, floors, telephones, floors, door handles and drawer pulls, and computer keyboards. Types of Contamination Removable contamination can be readily transferred from one surface to another. Removable contamination may present an internal and external hazard because it can be picked up on the skin and ingested. Fixed contamination cannot be readily removed and generally does not present a significant hazard unless the material comes loose or is present large enough amounts to be an external hazard. Types of Surveys There are two types of survey methods used: 1) a direct (or meter) survey, and 2) a wipe (or smear) survey. Direct surveys, using a Geiger-Mueller (GM) detector or scintillation probe, can identify gross contamination (total contamination consisting of both fixed and removable contamination) but will detect only certain isotopes. Wipe surveys, using “wipes” such as cotton swabs or filter papers counted on a liquid scintillation counter or gamma counter can identify removable contamination only but will detect most isotopes used at the U of I. Wipe surveys are the most versatile and sensitive method of detecting low-level removable contamination in the laboratory. -
Optimization of a Gas Flow Proportional Counter for Alpha Decay
Optimization of a gas flow proportional counter for alpha decay measurements Elena Ceballos Romero Master Thesis Institut f¨urKernphysik Mathematisch-Naturwissenschaftliche Fakult¨at Westf¨alische Wilhelms-Universit¨atM¨unster Prof. Dr. Alfons Khoukaz October 2012 III I am among those who think that science has great beauty. A scientist in his laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale. We should not allow it to be believed that all scientific progress can be reduced to mechanisms, machines, gearings, even though such machinery has its own beauty. -Marie Curie A magdalena, por ponerme en este camino. A mis padres, por siempre acompa~narmeen ´el. IV V I certify that I have independently written this thesis and no other sources than the mentioned ones have been used. Referent: Prof. Dr. Alfons Khoukaz Correferent: Dr. Mar´ıaVilla Alfageme VI Contents 1. Introduction 1 2. Introduction to natural radiations 5 2.1. Radioactivity . .5 2.1.1. Decay laws . .5 2.1.2. Activity . .7 2.2. Decays . .7 2.2.1. Alpha decay . .7 2.2.2. Beta decay . .9 2.2.3. Gamma decay . 11 3. Theoretical background: Gas-filled detectors 13 3.1. General properties . 13 3.1.1. Number of ion pairs formed . 14 3.1.2. Behaviour of charged particles in gases . 14 3.1.3. Operational modes of gas detectors . 15 3.2. Proportional counters: gas multiplication effect . 17 3.3. Gas flow detectors . 18 4. Experimental set-up 21 4.1. Detector . 21 4.1.1. -
Radiation Glossary
Radiation Glossary Activity The rate of disintegration (transformation) or decay of radioactive material. The units of activity are Curie (Ci) and the Becquerel (Bq). Agreement State Any state with which the U.S. Nuclear Regulatory Commission has entered into an effective agreement under subsection 274b. of the Atomic Energy Act of 1954, as amended. Under the agreement, the state regulates the use of by-product, source, and small quantities of special nuclear material within said state. Airborne Radioactive Material Radioactive material dispersed in the air in the form of dusts, fumes, particulates, mists, vapors, or gases. ALARA Acronym for "As Low As Reasonably Achievable". Making every reasonable effort to maintain exposures to ionizing radiation as far below the dose limits as practical, consistent with the purpose for which the licensed activity is undertaken. It takes into account the state of technology, the economics of improvements in relation to state of technology, the economics of improvements in relation to benefits to the public health and safety, societal and socioeconomic considerations, and in relation to utilization of radioactive materials and licensed materials in the public interest. Alpha Particle A positively charged particle ejected spontaneously from the nuclei of some radioactive elements. It is identical to a helium nucleus, with a mass number of 4 and a charge of +2. Annual Limit on Intake (ALI) Annual intake of a given radionuclide by "Reference Man" which would result in either a committed effective dose equivalent of 5 rems or a committed dose equivalent of 50 rems to an organ or tissue. Attenuation The process by which radiation is reduced in intensity when passing through some material. -
Ionization Chamber Type Survey Instruments
Chapter 5: Instrumentation Objectives: • Summarize the advantages and disadvantages of the different types of devices used to monitor individuals for radiation exposure. • Describe the principal advantages and disadvantages of air ionization chamber type survey instruments. • Describe the principal advantages and disadvantages of Geiger-Müller (GM) type survey instruments. SAT Chapter 5 - Instrumentation 2 Objectives: • Describe the important characteristics of any radiation monitoring instrument and why these characteristics are important for obtaining accurate results. • Select the appropriate survey instrument for a task, and be able to ensure its proper operation and be able to interpret the results obtained. SAT Chapter 5 - Instrumentation 3 Overview: • Humans cannot detect ionizing radiation with any of our senses. But, we need to know: – Is ionizing radiation present? – Are we receiving dose from ionizing radiation? – How much dose have we received (mrem)? – Is there contamination present? • We use instruments which respond to ionizing radiation. The type of instrument needed depends on the type and levels of radiation that are present. • Radiation detectors respond to ionizations or excitations created by radiation interaction with the detector media. Detectors can either be gas-filled or solid materials. SAT Chapter 5 - Instrumentation 4 Instrumentation Gas-filled instruments for detecting ionizing radiation utilize the concept that radiation interaction with atoms can cause ionizations. The ions are collected and measured. This is used to provide information on the presence of radioactive material (contamination) or the dose rate in an area. Hi + Volt - Ionizing Radiation (MEDIUM) SAT Chapter 5 - Instrumentation 5 IONIZATION CURVE 1015 I II III IV V VI 1012 Proportional 109 Continuous Geiger- Discharge Müller 106 α # of Ion Pairs Collected Pairs Ion of # 103 β 0 0 200 400 600 800 1000 1200 1400 1600 Applied Voltage, V SAT Chapter 5 - Instrumentation 6 Ionization Chamber Ionization chambers measure the ionization of air. -
Radiation Fields Using a Tepc*
XA00XC014 EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERN/TIS-RP/95-14/CF A STUDY OF BUILD-UP EFFECTS IN HIGH-ENERGY RADIATION FIELDS USING A TEPC* M. Hofert1), A. Aroua2), A. V. Sannikov3) and G. R. Stevenson1) !) CERN, European Laboratory for Particle Physics, CH 1211 Geneva 23, Switzerland 2) IAR, Institute for Applied Radiophysics, CH 1015 Lausanne, Switzerland 3) IHEP, Institute for High-Energy Physics, RU 142284 Protvino, Russia * Supported by EU Research Contract FI3P-CT92-0026 Abstract A dose of 2 mSv close to the body surface of a pregnant woman is considered by ICRP to assure a dose limit of 1 mSv to the foetus. Such an assumption depends on the energy spectrum and composition of the external radiation field and it was tested in radiation fields containing high-energy particles similar to those found around high-energy particle accelerators and in air-craft. Measurements of dose and dose equivalent were performed as a function of wall thickness using a tissue-equivalent proportional counter (TEPC) in radiation fields at the CERN-EU Reference Radiation Facility. Results are presented both with respect to integral quantities and event size spectra. The decrease in dose and dose equivalent at a depth equivalent to that of the foetus was typically 10% in a high-energy stray radiation field and in the case of Pu- Be source neutrons amounted to only 30%. It is concluded that it would be prudent under such exposure conditions to limit the dose of a pregnant woman to 1 mSv in order to assure that the dose to the foetus remains below the same limit. -
Thermo Micro Rem / Micro Sievert Tissue Equivalent Survey Meters
A D V A N C E D T E C H N O L O G Y F O R A S A F E R W O R L D Micro Rem/Sievert Tissue Equivalent Survey Meter The Micro Rem and Micro Sievert models are lightweight, portable survey meters for applications where accurate dose rate measurements of low radiation levels are required. Accurate down to background levels, the Micro Rem and Micro Sievert read absorbed dose rate directly so no conversion from mR/h is required. APPLICATIONS The tissue-equivalent scintillator used in the Micro Rem and Micro Sievert gives them a nearly flat, rem energy response. This rem response is based • Routine low/medium level gamma dose rate on the deep dose equivalent index for 1 cm (0.39”) depth, uniparallel surveys directional beam as calculated on the ICRU standard sphere. • Confirming radiation boundaries • Monitoring items for unrestricted release These instruments give tissue equivalent photon response for x-ray and • X-ray surveys, using the expanded low gamma radiation from environmental levels of 0-20 μrem/h (o-0.2 μ Sv/h) energy range option full scale up to normal survey levels of 200 mrem/h (2 mSv/h) full scale. Rugged construction and quality components make the Micro Rem and Options Micro Sievert durable, and they are easy to service. Internal components You can “customize” your instrument with practical are laid out on modular circuit boards. Span, HV and calibration pots (one options to match the requirements of your survey for each range) are clearly marked. -
Radioactive Materials Transportation and Incident Response
RADIOACTIVE MATERIALS TRANSPORTATION AND INCIDENT RESPONSE U.S. Department of Energy Transportation Emergency Preparedness Program Q&A About Incident Response 04/12 QA Phone Number Radio Frequency Law Enforcement ____________________________________ RADIOACTIVE Fire ___________________________________________ MATERIALS Medical ____________________________________________ TRANSPORTATION AND INCIDENT RESPONSE State Radiological Assistance ___________________________ Local Government Official ______________________________ Local Emergency Management Agency ___________________ State Emergency Management Agency ___________________ HAZMAT Team ______________________________________ Water Pollution Control ________________________________ CHEMTEL (Toll-free US & Canada) 1-800-255-3924 _________ CHEMTREC (Toll-free US & Canada) 1-800-424-9300 _______ CHEMTREC (Outside US) 1-703-527-3887 ________________ National Response Center (Toll-free US & Canada) 1-800-424-8802 ____________ In Washington, D.C. 1-202-267-2675 _____________________ Military Shipments (DoD) Call Collect 1-703-697-0218 _______ Other: ______________________________________________ Other: ______________________________________________ QQ&A About Incident Response NOTES TABLE OF CONTENTS What is radiation?.................................................................................... 2 ______________________________________________ What is radiation exposure? .................................................................... 3 ______________________________________________ -
Radiation Safety
RADIATION SAFETY FOR LABORATORY WORKERS RADIATION SAFETY PROGRAM DEPARTMENT OF ENVIRONMENTAL HEALTH, SAFETY AND RISK MANAGEMENT UNIVERSITY OF WISCONSIN-MILWAUKEE P.O. BOX 413 LAPHAM HALL, ROOM B10 MILWAUKEE, WISCONSIN 53201 (414) 229-4275 SEPTEMBER 1997 (REVISED FROM JANUARY 1995 EDITION) CHAPTER 1 RADIATION AND RADIOISOTOPES Radiation is simply the movement of energy through space or another media in the form of waves, particles, or rays. Radioactivity is the name given to the natural breakup of atoms which spontaneously emit particles or gamma/X energies following unstable atomic configuration of the nucleus, electron capture or spontaneous fission. ATOMIC STRUCTURE The universe is filled with matter composed of elements and compounds. Elements are substances that cannot be broken down into simpler substances by ordinary chemical processes (e.g., oxygen) while compounds consist of two or more elements chemically linked in definite proportions. Water, a compound, consists of two hydrogen and one oxygen atom as shown in its formula H2O. While it may appear that the atom is the basic building block of nature, the atom itself is composed of three smaller, more fundamental particles called protons, neutrons and electrons. The proton (p) is a positively charged particle with a magnitude one charge unit (1.602 x 10-19 coulomb) and a mass of approximately one atomic mass unit (1 amu = 1.66x10-24 gram). The electron (e-) is a negatively charged particle and has the same magnitude charge (1.602 x 10-19 coulomb) as the proton. The electron has a negligible mass of only 1/1840 atomic mass units. The neutron, (n) is an uncharged particle that is often thought of as a combination of a proton and an electron because it is electrically neutral and has a mass of approximately one atomic mass unit. -
Selection of Survey Meters for Monitoring
Selection of Survey Meters for Procedure: 7.522 Created: 5/23/16 Monitoring Version: 1.0 Revised: A. Purpose To aid in the selection of a proper survey meter for all required surveys. B. Applicability/scope This procedure applies to Columbia University, including Morningside, Nevis, LDEO, Barnard College, Manhatanville and the Medical Center campuses, NewYork-Presbyterian and the New York Psychiatric Institute. C. Definitions Beta emitter: radionuclides that decay by beta emission Gamma emitters: radionuclides that decay by gamma emission RAM: Radioactive Materials GM: Geiger Mueller Counter cpm: Counts Per Minute NaI(Tl): Sodium Iodide Counter LSC: Liquid Scintillation Counter D. Procedures There are two types of surveys typically performed in areas where RAM is used or stored. The first survey looks for ambient radiation exposure. The second one is to determine the presence of removable contamination. When performing ambient radiation exposures surveys, the instrument of choice is an ion chamber. Ion chambers are independent of the energy from incident gamma or x-ray radiation and the reading output is in roentgen per hour. Some ion chambers have a sliding panel on the bottom of the detector to provide exposure rate estimates for beta emitters. To perform surveys for potentially contaminated areas (i.e. hands, feet, bench tops, etc.) the instrument of choice is a Geiger-Muller Counter (GM). GM survey meters are dependent on the incident radiation type and energy and can paralyze in high radiation fields. This instruments is sensitive to beta radiation and the readout to be used is counts per minute (cpm). Do not use for exposure rate measurements unless the instrument has been Selection of Survey Meters for Procedure: 7.522 Created: 5/23/16 Monitoring Version: 1.0 Revised: calibrated for the specific energy or the radionuclide for which the survey is being performed.