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The National Measurement System for Ionizing Radiations

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The National Measurement System for Ionizing Radiations NATL INST. OF STAND & TECH NJST PUBLICATIONS AlllDb fib2Sfll NBSIR 75-946 The National Measurement System for Ionizing Radiations Randall S. Caswell Center for Radiation Research Institute for Basic Standards National Bureau of Standards Washington, D.C. 20234 December 1977 Issue Date April 1978 » \ 7 « z M ^- at '•rAu 0* /oo DEPARTMENT OF COMMERCE »NAL BUREAU OF STANDARDS y^' IS' ^Hio r NBSIR 77-946 THE NATIONAL MEASUREMENT SYSTEM FOR IONIZING RADIATIONS Randall S. Caswell with the collaboration of John W. Bartlett, Bert T. Coursey, Charles E. Dick, Margarete Ehrlich, Charles Eisenhauer, Elmer H. Eisenhower, Everett G. Fuller, J. M. Robin Hutchinson, Robert Loevinger, William L. McLaughlin, Francis J. Schima, and James M. Wyckoff Center for Radiation Research Institute for Basic Standards National Bureau of Standards Washington, D.C. 20234 December 1977 Issue Date April 1978 U.S. DEPAFtTMENT OF COMMERCE, Juanita M. Kreps, Secretary Dr. Sidney Harman, Under Secretary Jordan J. Baruch, Assistant Secretary for Science and Technology NATIONAL BUREAU OF STANDARDS. Ernest Ambler, Director CONTENTS EXECUTIVE SUMMARY I 1 . INTRODUCTION , 4 2. STRUCTURE OF THE MEASUREMENT SYSTEM 4 2.1 Conceptual System 5 2.2 Basic Technical Infrastructure 6 2.2.1 Documentary Specification System 6 2.2.1.1 Standardization Institutions 6 2.2.1.2 Survey of Documentary Standards 8 2.2.2 Instrumentation System 9 2.2.2.1 Measurement Tools and Techniques 9 2.2.2.2 The Instrumentation Industry 9 2.2.3 Reference Data 10 2.2.4 Reference Materials 11 2.2.5 Science and People 11 2.3 Realized Measurement Capabilities 12 2.4 Dissemination and Enforcement Network 12 2.4.1 Central Standards Authorities 12 2.4.2 State and Local Offices of Weights and Measures 13 2.4.3 Standards and Testing Laboratories and Services 13 2.4.4 Regulatory Agencies 13 2.5 Direct Measurements Transactions Matrix 16 2.5.1 Analysis of Suppliers and Users 16 2.5.2 Highlights re Major Users 16 2.6 Study Method for Ionizing Radiation Measurement System 16 2/3 MEASUREMENT SYSTEM STRUCTURE, IMPACT, STATUS, AND TRENDS BY MAJOR CATEGORIES OF RADIATION USERS 16 2/3. A Medical 16 2/3. A. 1 Direct Users of Radiation 19 2/3. A. 2 Manufacturers 19 2/3. A. 3 Standards and Calibration Laboratories 20 2/3. A. 4 S:ructure and Problems of the Medical Radiation Measurement System 21 2/3. B Nuclear Pouer 23 2/3. B.l Nuclear Fuel Cycle Operations 25 2/3. B. 1.1 Scope and Status of the Nuclear Power Industry .... 25 2/3. B.l. 2 Measurement Objectives 27 2/3. B.l. 3 Measurement Methods 27 • ' 2/3. B.l. 4 Status of Measurement Technology 28 2/3. B.l. 5 Measurement System Infrastructure 29 2/3. B.l. 6 Summary of Conclusions of the Assessment of the Nuclear Fuel Materials Measurement System 30 2/3. B. 2 Nuclear Reactor Design Data and Operations 31 2/3. B. 2.1 Design Data for Fission Reactors 31 ii 2/3. B. 2. 2 Design Data for Fusion Reactors (Magnetically- confined plasmas and laser fusion) 2/3. B. 2. 3 In-Reactor Neutron Measurements 33 2/3. B. 2. 4 Note on the relationship of the NBS Neutron Standards Program to the Department of Energy Programs 34 2/3. C Industrial Radiation Processing 34 2/3.0 Defense 35 2/3. D.l X-rays, Gamma-rays, and Electron Measurements for Defense .... 37 2/3. D. 2 Radioactivity Measurements for Defense 38 2/3. D. 3 Neutron Measurements for Defense 39 2/3. E Chemical Analysis 39 2/3. F Radiation Measurement System for Science 40 2/3. G Environmental Radioactivity Measurement 42 2/3. H Miscellaneous Radiation Applications 45 2/3.1 Personnel Monitoring 50 2/3.1.1 Nature of Activity and Present Status 50 2/3.1.2 Basic Problems and Needs 50 2/3.1.3 Size and Importance of Personnel Monitoring Activities 51 2/3.1.4 Structure of the Radiation Measurement System for Personnel Monitoring 53 2/3.1.5 Conclusions 55 3. IMPACT, STATUS AND TRENDS OF MEASUREMENT SYSTEM 55 3.1 Impact of Measurements 56 3.1.1 Functional, Technological and Scientific Applications 56 3.1.2 Economic Impacts -- Costs and Benefits 56 3.1.3 Social, Human, Person-in-the-Street Impacts 56 3.2 Status and Trends of the System 57 4. SURVEY OF NBS SERVICES 58 4.1 The Past . 58 4.2 The Present 58 4.2.1 Description of NBS Services 58 4.2.2 Users of NBS Services 58 4.2.3 Alternate Sources of Calibration Services 59 4.2.4 Funding Sources for NBS Services 59 4.2.5 Mechanism for Supplying Services 59 4.3 Impact of NBS Services 59 4.3.1 Economic Impact of Major User Classes 59 4.3.2 Technological Impact of Services 59 4.3.3 Pay-Off from Changes in NBS Services 59 4.4 Evaluation of the NBS Program 59 4.5 The Future 61 5. SUMMARY AND CONCLUSIONS 61 iii APPENDIX A. METHODOLOGY OF THE STUDY A-1 APPENDIX B. ORGANIZATIONS CONCERNED WITH RADIATION B-1 APPENDIX C. INFORMATION ON MEDICAL RADIATION INDUSTRY C-1 APPENDIX D. ASSESSMENT OF THE NUCLEAR FUEL MATERIALS MEASUREMENT SYSTEM D-1 APPENDIX E. RADIATION PROCESSES OF COMMERCIAL INTEREST E-1 APPENDIX F. ENVIRONMENTAL RADIOACTIVITY MEASUREMENT SYSTEM INFORMATION F-1 APPENDIX G. PERSONNEL MONITORING SERVICES IN THE UNITED STATES G-1 APPENDIX H. STANDARDIZATION ACTIVITIES H-1 REFERENCES R-1 LIST OF FIGURES Figure 1. Medical radiation measurement system for x and gamma rays 18 Figure 2. Measurement system for radioactivity standards and radiopharmaceuticals used in nuclear medicine 18 Figure 3. Comparison of radiation therapy machine calibrations by the RPC with those in use at institutions 20 Figure 4. Comparison of tumor dose delivered (RPC) with that prescribed (institution) 20 Figure 5. Medical dosimetry calibration system 22 Figure 6. Nuclear power reactors in the United States (ERDA, 1975) 24 Figure 7. Outline of nuclear power industry operations . 26 Figure 8. Possible NBS interactions for nuclear industry measurements and standards . 30 Figure 9. Structure of the environmental radioactivity measurement system 43 Figure 10. Environmental radioactivity measurements system in the southeastern United States 46 Figure 11. Structure of the personnel monitoring measurement system ... 54 LIST OF TABLES Table 1. Organization of the CRR radiation measurement system study 5 Table 2. Radiations, quantities, and units 5 Table 3. Examples of radiation detectors 10 Table 4. Some regulations and regulatory guides for ionizing radiations . 14 Table 5. Direct measurement transactions matrix 17 Table 6. Classification of medical radiation users by activity and specific interest 18 Table 7. Survey of diagnostic and therapeutic x-ray machines, Suffolk County, New York, 1972 22 Table 8. Laboratories participating in the interlaboratory LMFBR reaction rate program (ILRR) 34 Table 9. Large radiation processing operations in the United States 36 Table 10. Measurement quantities involved in a photon- or charged particle-induced cross section measurement . 41 Table 11. Some NBS contributions to ionizing radiation measurements for science ... 43 Table 12. Industries employing radiation gauging devices 47 Table 13. Applications, of radiation gauging devices in selected industries 47 Table 14. Relationship between voltage and radiographic application 48 Table 15. NRC regulations applicable to industrial use of radioisotopes 49 Table 16. Estimates o1^ workers monitored (1969-70) 52 Table 17. Some standards and guides for personnel monitoring 53 Table 18. Effect of changes in NBS services for ionizing radiations 60 iv THE NATIONAL MEASUREMENT SYSTEM FOR IONIZING RADIATIONS Randan S. Caswell Center for Radiation Research Institute for Basic Standards December 1977 EXECUTIVE SUMMARY attained by establishing traceability to NBS; and (2) the great majority of state health In this study the structure of the National departments with responsibility for radiation Measurement System for Ionizing Radiation^ control would be benefited by a program of has been investigated for eight classes of technical assistance in radiation measurement. radiation users: medical, nuclear power, In response to these needs, the NBS Center industrial radiation processing, defense, for Radiation Research (CRR) has (1) instituted environmental, science, chemical analysis, a program of measurement assurance testing to and miscellaneous radiation applications. In establish traceability with quality assurance addition two fields of increasing importance laboratories of the Nuclear Regulatory Com- to all radiation users were investigated: mission, the Environmental Protection Agency, regulatory control of radiation and personnel and other regulatory agencies, and (2) insti- monitoring. Needed major actions on the part tuted a national radiation measurement of the National Bureau of Standards were calibration system for the benefit of the identified particularly for nuclear power and states, regional calibration laboratories, its related environmental and safety impacts, and regulatory agencies. medical applications of radiation, assistance to regulatory control of radiation and The study of personnel monitoring has measurement assurance for personnel monitor- found that in the United States about 800,000 ing. Brief summaries of system structure and persons considered to be radiation workers identified needs are given below. wear personnel monitors. The majority of personnel radiation monitoring services are The regulatory control of radiation is a supplied by fewer than 20 commercial suppliers, divided responsibility among several groups: although government laboratories and the the Nuclear Regulatory Commission, the military services largely provide their own Environmental Protection Agency, the Food and service. Two needs are apparent: (1) a Drug Administration including the Bureau of reliable measurement assurance testing labora- Radiological Health, the Occupational Safety tory is needed to test monitoring services -- and Health Administration of the Department this could be NBS or another laboratory of Labor assisted by the National Institute traceable to and in close contact with NBS; of Occupational Safety and Health of HEW, the and (2) monoenergetic neutron calibration U.S.
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