NCRP REPORT No 144 RADIATION PROTECTION FOR PARTICLE ACCELERATOR FACILITIES N C R P National Council on Radiation Protection and Measurements NCRP Report No 144 Radiation Protection for Particle Accelerator Facilities Recommendations of the NATIONAL COUNCIL ON RADIATION PROTECTION AND MEASUREMENTS Issued December 31, 2003 Revised March 4, 2005 National Council on Radiation Protection and Measurements 7910 Woodmont Avenue, Suite 400/Bethesda, Maryland 20814-3095 LEGAL NOTICE This Report was prepared by the National Council on Radiation Protection and Measurements (NCRP) The Council strives to provide accurate, complete and useful information in its documents However, neither the NCRP, the members of NCRP, other persons contributing to or assisting in the preparation of this Report, nor any person acting on the behalf of any of these parties: (a) makes any warranty or representation, express or implied, with respect to the accuracy, completeness or usefulness of the information contained in this Report, or that the use of any information, method or process disclosed in this Report may not infringe on privately owned rights; or (b) assumes any liability with respect to the use of, or for damages resulting from the use of any information, method or process disclosed in this Report, under the Civil Rights Act of 1964, Section 701 et seq as amended 42 U.S.C Section 2000e et seq (Title VII) or any other statutory or common law theory governing liability Library of Congress Cataloging-in-Publication Data National Council on Radiation Protection and Measurements Radiation protection for particle accelerator facilities : recommendations of the National Council on Radiation Protection and Measurements p cm (NCRP report ; no 144) ‘‘Issued December 2003.’’ Rev ed of: Radiation protection design guidelines for 0.1-100 MeV particle accelerator facilities 1977 Includes bibliographical references and index ISBN 0-929600-77-0 Particle accelerators Safety measures Particle accelerators Shielding (Radiation) Radiation Safety measures I National Council on Radiation Protection and Measurements Radiation protection design guidelines for 0.1100 MeV particle accelerator facilities II Title III Series TK9340.N39 2003 621.48 dc22 2003061402 Copyright © National Council on Radiation Protection and Measurements 2003 All rights reserved This publication is protected by copyright No part of this publication may be reproduced in any form or by any means, including photocopying, or utilized by any information storage and retrieval system without written permission from the copyright owner, except for brief quotation in critical articles or reviews [For detailed information on the availability of NCRP publications see page 479.] Preface The National Council on Radiation Protection and Measurements (NCRP) Report No 51, Radiation Protection Design Guidelines for 0.1–100 MeV Particle Accelerator Facilities, was published in 1977 Since then, NCRP has issued two reports that discuss specific radiological protection issues at particle accelerators: NCRP Report No 72, Radiation Protection and Measurements for Low-Voltage Neutron Generators and NCRP Report No 79, Neutron Contamination from Medical Electron Accelerators NCRP Report No 88, Radiation Alarms and Access Control Systems is also of interest for those who operate accelerators, but until now, there has been no recent attempt to readdress the entire issue of accelerator radiological protection in a single report In light of the significant experience with the operation and design of accelerator facilities and the increased understanding of accelerator radiation environments obtained over the past 25 y, it was considered appropriate to revise NCRP Report No 51 while maintaining its extremely valuable practical utility Accordingly, Scientific Committee 46-8 was established and given the general charge to ‘‘review and update Report No 51 to include: new shielding data, extension of the energy range up to the gigaelectron volt region, skyshine radiation, transmission of radiation through ducts and labyrinths, induced radioactivity, and environmental considerations such as radioactive airborne and liquid effluents.’’ Some of the material in this Report is historical and refers to studies performed many decades ago In such cases, the quantities, units and references as formatted are retained in their original form This publication was made possible, in part, by Grant Number R24 CA74296-05 from the National Cancer Institute (NCI) and its contents are the sole responsibility of the NCRP and not necessarily represent the official views of the NCI, National Institutes of Health Additionally, publication of this Report was supported in part by the Idaho Accelerator Center, a research center of Idaho State University, Pocatello, Idaho Those who served on Scientific Committee 46-8 were: iii iv / PREFACE Ralph H Thomas, Chairman University of California Members W Robert Casey Brookhaven National Laboratory Upton, New York J Donald Cossairt Fermi National Accelerator Laboratory Batavia, Illinois Lester A Slaback, Jr National Institute of Standards and Technology Gaithersburg, Maryland Geoffrey B Stapleton Thomas Jefferson National Accelerator Facility Newport News, Virginia Keran O’Brien Northern Arizona State University Flagstaff, Arizona William P Swanson* Lawrence Berkeley National Laboratory Berkeley, California Norman Rohrig National Engineering and Environmental Laboratory Idaho Falls, Idaho Consultants Lutz E Moritz TRIUMF, National Laboratory for Particle and Nuclear Physics Vancouver, Canada Vaclav Vylet Duke University Medical Center Durham, North Carolina Advisor David R Perry Rutherford Appleton Laboratory Chilton, Oxon, United Kingdom NCRP Secretariat Constantine J Maletskos, Consultant (1998–2003) Thomas M Koval, Senior Staff Scientist (1993–1998) James A Spahn, Senior Staff Scientist (1986–1993) Cindy L O’Brien, Managing Editor The Council wishes to express its appreciation to the Committee members for the time and effort devoted to the preparation of this Report Thomas S Tenforde President *deceased Contents Preface iii Executive Summary 1 Introduction 1.1 Purpose 1.2 Scope 1.3 Particle Accelerator Safety 1.4 Regulatory and Advisory Agencies 1.4.1 Federal Regulation 1.4.2 State Regulation 1.4.3 Local (County, City) Regulation 1.4.4 Advisory Organizations 1.4.4.1 International Agencies 1.4.4.2 National Organizations 1.5 Radiological Protection Standards 6 7 8 9 10 10 Particle Accelerators and Accelerator Facilities 2.1 Particle Accelerators—Definitions 2.2 Classification of Particle Accelerators 2.3 Brief Historical Review 2.4 Accelerator Radiation 2.5 Ion and Electron Sources 2.6 Particle Accelerating Schemes 2.7 Beam Delivery Systems 2.8 Beam Stops 2.9 Auxiliary Systems 2.9.1 High-Voltage and Microwave Power Supplies 2.9.2 Cooling Systems 2.9.3 Vacuum Systems 2.10 Summary of the General Specifications and Parameters of Accelerators 2.11 Applications of Accelerators 2.12 Future Developments in Accelerators 2.13 Siting and Layout 12 12 12 13 17 18 19 23 24 25 25 27 27 v 28 28 29 29 vi / CONTENTS Sources of Ionizing Radiation from Accelerators 3.1 Introduction 3.2 General Considerations 3.3 Radiation Production at Electron Accelerators 3.3.1 General 3.3.2 Electron Beams 3.3.3 Photon Fields 3.3.3.1 External Bremsstrahlung 3.3.3.2 High Energies 3.3.4 Neutron Production 3.3.5 Muon Production 3.3.6 Electromagnetic Cascade 3.4 Radiation Protection at Proton Accelerators 3.4.1 General 3.4.2 Proton Beams 3.4.3 Neutron Yields 3.4.3.1 Neutron Production at Low Energies (E Ͻ 200 MeV) 3.4.3.2 Neutron Production at Intermediate Energies (200 MeV Յ E Յ GeV) 3.4.3.3 Neutron Production at High Energies (E Ն GeV) 3.4.4 Muon Production 3.4.5 Hadronic (Nuclear) Cascade 3.4.5.1 General 3.4.5.2 Qualitative Description of the Hadronic Cascade 3.4.6 Radiation Environment 3.4.6.1 Neutron Energy Spectra 3.4.6.2 Spectra Outside Accelerator Shielding 3.5 Radiation Production at Accelerators of Positive Ions 3.5.1 General 3.5.2 Light Ions 3.5.3 Heavy Ions 3.6 Radioactivation at Accelerators 3.6.1 General 3.6.2 Activation by Low-Energy Particles 3.6.3 Activation by High-Energy Particles 33 33 35 39 39 40 41 41 49 59 62 65 70 70 73 73 102 103 105 108 112 112 113 118 132 132 133 136 Radiation Shielding at Accelerators 4.1 Introduction 4.2 Theory of Radiation Transport 4.2.1 Introduction 4.2.1.1 Construct of the Boltzmann Equation 146 146 148 148 150 74 80 80 98 101 101 CONTENTS 4.3 4.4 4.5 4.6 / 4.2.1.2 Approximate Solutions of the Boltzmann Equation 4.2.2 Computer Codes for Shielding Calculations 4.2.2.1 The Monte-Carlo Method 4.2.2.2 MARS 4.2.2.3 EGS4 Code System 4.2.2.4 FLUKA 4.2.2.5 NMTC/HETC 4.2.2.6 MCNP 4.2.2.7 Integrated Tiger Series 4.2.2.8 MORSE-CGA 4.2.2.9 TOMCAT 4.2.2.10 MUSTOP 4.2.2.11 MUCARLO 4.2.2.12 MUON89 4.2.2.13 SHIELD11 4.2.2.14 PHOTON 4.2.2.15 STAC8 4.2.2.16 SKYSHINE-KSU 4.2.2.17 SKYSHINE III 4.2.2.18 TRIPOLI Practical Shield Design 4.3.1 General 4.3.2 Photon Transmission 4.3.3 Neutron Transmission 4.3.4 Scattering—Albedo 4.3.5 Scatter Paths Radiation Goals and Area Occupancy and Use Factors Determination and Specification of the Beam-Loss Terms Shielding of Electron Accelerators in the Energy Range from to 100 MeV 4.6.1 Source Term for Simple Accelerators 4.6.1.1 Workload 4.6.1.2 Primary and Secondary Barriers and the Orientation (Use) Factor 4.6.1.3 Occupancy Factor 4.6.2 Primary Barriers for Photons 4.6.3 Secondary Barriers for Photons 4.6.3.1 Leakage Radiation 4.6.3.2 Scattered Photons 4.6.4 Shielding Against Neutrons vii 152 154 154 156 156 157 157 158 158 158 159 159 159 160 160 160 160 161 161 161 161 161 163 167 178 179 183 185 188 189 190 191 191 191 194 194 194 195 viii / CONTENTS 4.7 Shielding of Large Electron Accelerator Facilities at Higher Energies (E Ͼ 100 MeV) 4.7.1 Review of Source Terms 4.7.1.1 Electromagnetic Cascade 4.7.1.2 Neutron Source Terms and Attenuation 4.7.2 Design of High-Intensity Beam Stops and Walls 4.7.3 Distributed Loss Issues 4.7.3.1 Synchrotron-Radiation Facilities 4.7.3.2 Photon Shielding Experiments 4.7.3.3 Generalized Loss Model 4.8 Proton Accelerators—Transverse Shielding 4.8.1 Particle Yields from the Proton-Nucleus Interaction 4.8.2 Proton Energies Below GeV 4.8.3 Proton Energies Above GeV—The Moyer Model 4.8.3.1 Introduction 4.8.3.2 Generalized Formulation of the Moyer Model 4.8.3.3 Determination of the Moyer Model Parameters 4.8.3.3.1 Attenuation Parameter 4.8.3.3.2 Angular-Relaxation Parameter 4.8.3.3.3 Source-Strength Parameter 4.8.3.4 Practical Examples 4.8.3.4.1 Point Source 4.8.3.4.2 Infinite Uniform Line Source 4.8.3.4.3 Finite Uniform Line Source 4.8.3.5 Conclusions and Limitations of the Moyer Model 4.9 Proton Accelerators—Forward Shielding 4.9.1 Proton Energies Below GeV 4.9.2 Hadronic Cascade Above GeV 4.9.3 Muon Shielding 4.10 Shielding Materials 4.10.1 Earth 4.10.2 Concrete 4.10.3 Other Hydrogenous Materials 4.10.4 Steel 4.10.5 Special Materials 4.10.5.1 Materials of High Atomic Number 4.10.5.2 Materials of Low Atomic Number 197 197 197 198 202 204 205 208 212 213 214 216 218 218 219 222 222 223 224 226 226 227 228 229 232 232 232 239 242 243 244 246 249 252 252 254 / ix 4.10.6 Special Considerations 4.11 Tunnels, Labyrinths and Ducts 4.11.1 Introduction 4.11.2 Design Example for Photons Using Albedos 4.11.3 Straight Penetrations—Neutrons and Photons 4.11.4 Transmission of Neutrons Through Labyrinths 4.11.5 Transmission of Neutrons Through Curved Tunnels 4.11.6 Door Design 254 255 255 257 CONTENTS Techniques of Radiation Measurement at Particle Accelerators 5.1 Introduction to Radiation Dosimetry at Particle Accelerators 5.2 Special Consideration of the Techniques of Radiation Dosimetry in Accelerator Environments 5.3 Application of ‘‘Conventional Techniques’’ to Measurements in Accelerator-Radiation Environments 5.3.1 Introduction 5.3.2 Ionization Chambers 5.3.3 Geiger-Mueller Counters 5.3.4 Thermoluminescence Dosimeters 5.4 Neutron Dosimetry at Particle Accelerators 5.4.1 Introduction 5.4.2 Passive Detectors Used for Neutron Dosimetry 5.4.2.1 Thermoluminescence Dosimeters 5.4.2.2 Nuclear Emulsions 5.4.2.3 Activation Detectors 5.4.2.4 Threshold Detectors 5.4.2.5 Moderated Detectors 5.4.2.6 Track-Etch Detectors 5.4.2.7 Bubble Detectors 5.4.3 Active Detectors Used for Neutron Dosimetry 5.4.3.1 Moderated Detectors 5.4.3.2 Fission Counters 5.4.4 Neutron Spectrometry 5.4.4.1 Bonner Spheres 5.4.4.2 Spectrum-Unfolding Methods 5.4.4.3 Proton-Recoil Counters 5.5 Mixed-Field Dosimetry 5.5.1 Introduction 5.5.2 Recombination Chambers 258 259 266 267 269 269 272 273 273 273 275 276 276 276 277 277 279 280 281 285 287 289 291 291 297 299 299 301 303 304 304 305 NCRP PUBLICATIONS 10 11 12 13 14 15 16 17 18 19 / 485 Radiation Protection and New Medical Diagnostic Approaches, Proceedings of the Eighteenth Annual Meeting held on April 6-7, 1982 (including Taylor Lecture No 6) (1983) Environmental Radioactivity, Proceedings of the Nineteenth Annual Meeting held on April 6-7, 1983 (including Taylor Lecture No 7) (1983) Some Issues Important in Developing Basic Radiation Protection Recommendations, Proceedings of the Twentieth Annual Meeting held on April 4-5, 1984 (including Taylor Lecture No 8) (1985) Radioactive Waste, Proceedings of the Twenty-first Annual Meeting held on April 3-4, 1985 (including Taylor Lecture No 9) (1986) Nonionizing Electromagnetic Radiations and Ultrasound, Proceedings of the Twenty-second Annual Meeting held on April 2-3, 1986 (including Taylor Lecture No 10) (1988) New Dosimetry at Hiroshima and Nagasaki and Its Implications for Risk Estimates, Proceedings of the Twenty-third Annual Meeting held on April 8-9, 1987 (including Taylor Lecture No 11) (1988) Radon, Proceedings of the Twenty-fourth Annual Meeting held on March 30-31, 1988 (including Taylor Lecture No 12) (1989) Radiation Protection Today—The NCRP at Sixty Years, Proceedings of the Twenty-fifth Annual Meeting held on April 5-6, 1989 (including Taylor Lecture No 13) (1990) Health and Ecological Implications of Radioactively Contaminated Environments, Proceedings of the Twenty-sixth Annual Meeting held on April 4-5, 1990 (including Taylor Lecture No 14) (1991) Genes, Cancer and Radiation Protection, Proceedings of the Twenty-seventh Annual Meeting held on April 3-4, 1991 (including Taylor Lecture No 15) (1992) Radiation Protection in Medicine, Proceedings of the Twentyeighth Annual Meeting held on April 1-2, 1992 (including Taylor Lecture No 16) (1993) Radiation Science and Societal Decision Making, Proceedings of the Twenty-ninth Annual Meeting held on April 7-8, 1993 (including Taylor Lecture No 17) (1994) Extremely-Low-Frequency Electromagnetic Fields: Issues in Biological Effects and Public Health, Proceedings of the Thirtieth Annual Meeting held on April 6-7, 1994 (not published) Environmental Dose Reconstruction and Risk Implications, Proceedings of the Thirty-first Annual Meeting held on April 12-13, 1995 (including Taylor Lecture No 19) (1996) Implications of New Data on Radiation Cancer Risk, Proceedings of the Thirty-second Annual Meeting held on April 3-4, 1996 (including Taylor Lecture No 20) (1997) The Effects of Pre- and Postconception Exposure to Radiation, Proceedings of the Thirty-third Annual Meeting held on April 2-3, 1997, Teratology 59, 181–317 (1999) 486 / 20 21 22 23 24 NCRP PUBLICATIONS Cosmic Radiation Exposure of Airline Crews, Passengers and Astronauts, Proceedings of the Thirty-fourth Annual Meeting held on April 1-2, 1998, Health Phys 79, 466–613 (2000) Radiation Protection in Medicine: Contemporary Issues, Proceedings of the Thirty-fifth Annual Meeting held on April 7-8, 1999 (including Taylor Lecture No 23) (1999) Ionizing Radiation Science and Protection in the 21st Century, Proceedings of the Thirty-sixth Annual Meeting held on April 5-6, 2000, Health Phys 80, 317–402 (2001) Fallout from Atmospheric Nuclear Tests—Impact on Science and Society, Proceedings of the Thirty-seventh Annual Meeting held on April 4-5, 2001, Health Phys 82, 573–748 (2002) Where the New Biology Meets Epidemiology: Impact on Radiation Risk Estimates, Proceedings of the Thirty-eighth Annual Meeting held on April 10-11, 2002, Health Phys 85, 1–108 (2003) Lauriston S Taylor Lectures No 10 Title The Squares of the Natural Numbers in Radiation Protection by Herbert M Parker (1977) Why be Quantitative about Radiation Risk Estimates? by Sir Edward Pochin (1978) Radiation Protection—Concepts and Trade Offs by Hymer L Friedell (1979) [available also in Perceptions of Risk, see above] From ‘‘Quantity of Radiation’’ and ‘‘Dose’’ to ‘‘Exposure’’ and ‘‘Absorbed Dose’’—An Historical Review by Harold O Wyckoff (1980) How Well Can We Assess Genetic Risk? Not Very by James F Crow (1981) [available also in Critical Issues in Setting Radiation Dose Limits, see above] Ethics, Trade-offs and Medical Radiation by Eugene L Saenger (1982) [available also in Radiation Protection and New Medical Diagnostic Approaches, see above] The Human Environment—Past, Present and Future by Merril Eisenbud (1983) [available also in Environmental Radioactivity, see above] Limitation and Assessment in Radiation Protection by Harald H Rossi (1984) [available also in Some Issues Important in Developing Basic Radiation Protection Recommendations, see above] Truth (and Beauty) in Radiation Measurement by John H Harley (1985) [available also in Radioactive Waste, see above] Biological Effects of Non-ionizing Radiations: Cellular Properties and Interactions by Herman P Schwan (1987) [available also in Nonionizing Electromagnetic Radiations and Ultrasound, see above] NCRP PUBLICATIONS 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 / 487 How to be Quantitative about Radiation Risk Estimates by Seymour Jablon (1988) [available also in New Dosimetry at Hiroshima and Nagasaki and its Implications for Risk Estimates, see above] How Safe is Safe Enough? by Bo Lindell (1988) [available also in Radon, see above] Radiobiology and Radiation Protection: The Past Century and Prospects for the Future by Arthur C Upton (1989) [available also in Radiation Protection Today, see above] Radiation Protection and the Internal Emitter Saga by J Newell Stannard (1990) [available also in Health and Ecological Implications of Radioactively Contaminated Environments, see above] When is a Dose Not a Dose? by Victor P Bond (1992) [available also in Genes, Cancer and Radiation Protection, see above] Dose and Risk in Diagnostic Radiology: How Big? How Little? by Edward W Webster (1992) [available also in Radiation Protection in Medicine, see above] Science, Radiation Protection and the NCRP by Warren K Sinclair (1993) [available also in Radiation Science and Societal Decision Making, see above] Mice, Myths and Men by R.J Michael Fry (1995) Certainty and Uncertainty in Radiation Research by Albrecht M Kellerer (1995) Health Phys 69, 446–453 70 Years of Radiation Genetics: Fruit Flies, Mice and Humans by Seymour Abrahamson (1996) Health Phys 71, 624–633 Radionuclides in the Body: Meeting the Challenge by William J Bair (1997) Health Phys 73, 423–432 From Chimney Sweeps to Astronauts: Cancer Risks in the Work Place by Eric J Hall (1998) Health Phys 75, 357–366 Back to Background: Natural Radiation and Radioactivity Exposed by Naomi H Harley (2000) Health Phys 79, 121–128 Administered Radioactivity: Unde Venimus Quoque Imus by S James Adelstein (2001) Health Phys 80, 317–324 Assuring the Safety of Medical Diagnostic Ultrasound by Wesley L Nyborg Health Phys 82, 578–587 (2002) Developing Mechanistic Data for Incorporation into Cancer and Genetic Risk Assessments: Old Problems and New Approaches by R Julian Preston Health Phys 85, 4–12 (2003) Symposium Proceedings No Title The Control of Exposure of the Public to Ionizing Radiation in the Event of Accident or Attack, Proceedings of a Symposium held April 27-29, 1981 (1982) Radioactive and Mixed Waste—Risk as a Basis for Waste Classifi cation, Proceedings of a Symposium held November 9, 1994 (1995) 488 / NCRP PUBLICATIONS Acceptability of Risk from Radiation—Application to Human Space Flight, Proceedings of a Symposium held May 29, 1996 (1997) 21st Century Biodosimetry: Quantifying the Past and Predicting the Future, Proceedings of a Symposium held on February 22, 2001, Radiat Prot Dosim 97, No (2001) NCRP Statements No Title ‘‘Blood Counts, Statement of the National Committee on Radiation Protection,’’ Radiology 63, 428 (1954) ‘‘Statements on Maximum Permissible Dose from Television Receivers and Maximum Permissible Dose to the Skin of the Whole Body,’’ Am J Roentgenol., Radium Ther and Nucl Med 84, 152 (1960) and Radiology 75, 122 (1960) X-Ray Protection Standards for Home Television Receivers, Interim Statement of the National Council on Radiation Protection and Measurements (1968) Specifi cation of Units of Natural Uranium and Natural Thorium, Statement of the National Council on Radiation Protection and Measurements (1973) NCRP Statement on Dose Limit for Neutrons (1980) Control of Air Emissions of Radionuclides (1984) The Probability That a Particular Malignancy May Have Been Caused by a Specifi ed Irradiation (1992) The Application of ALARA for Occupational Exposures (1999) Extension of the Skin Dose Limit for Hot Particles to Other External Sources of Skin Irradiation (2001) Other Documents The following documents of the NCRP were published outside of the NCRP report, commentary and statement series: Somatic Radiation Dose for the General Population, Report of the Ad Hoc Committee of the National Council on Radiation Protection and Measurements, May 1959, Science 131 (3399), February 19, 1960, 482–486 Dose Effect Modifying Factors In Radiation Protection, Report of Subcommittee M-4 (Relative Biological Effectiveness) of the National Council on Radiation Protection and Measurements, Report BNL 50073 (T-471) (1967) Brookhaven National Laboratory (National Technical Information Service, Springfield, Virginia) Index Accelerating schemes 19–23 Activation detectors 280–285 Aerosols 319 Albedo 178–183 ALARA (as low as reasonably achievable) 184 Angular relaxation parameter 223–224 Applications of accelerators 28 Approximation B 67 Area occupancy 184–185 Attenuation coefficient 66 Attenuation length 167, 217–218 Attenuation parameter 222–223 thick-target properties for radiation protection 44–49 Bubble detectors 289–290 Buildup factor 219 Cascade neutrons 88 Classification 12 Collective exposure 336–337, 347–348, 352–355 Compton minimum 49, 70 Computer shielding calculation codes 154–161 CASIM 156 EGS4 code system 156 FLUKA 157 HERMES 158 HETC-3STEP 158 Integrated Tiger Series 158 LAHET 158 MARS 156 MCNP 158 Monte-Carlo method 154–156 MORSE-CGA 158 MUCARLO 159 MUON89 160 MUSTOP 159 NMTC/HETC 157 PHOTON 160 SHIELD11 160 SKYSHINE III 161 SKYSHINE-KSU 161 STAC8 160 TOMCAT 159 TRIPOLI 161 Contamination standards, surface 369–371 detection of radioactivity 369–370 mixtures of radionuclides 370–371 Barriers (shield) 191–194 Beam delivery 23 Beam-loss source terms, determination and specification 185–188, 204 Beam stops 24, 202–204 Boltzmann equation 150–154 approximate solutions and comparisons 152–154 concept of importance 153 construct 150–151 Bonner spheres 299–301 energy response 300–301 operation 299–300 passive versus active thermal neutron detection 300–301 Bremsstrahlung 34, 41, 42, 44–59 absorbed doses related to the forward spike 51 broad field 49 critical energy 41 doses at large angles 52–59 forward spike 51 high energies 49–59 radiation length 42 489 490 / INDEX radionuclides difficult to detect 369, 370 release limits 370 Continuous wave acceleration 17, 272 Control of radioactive material 356, 366–371 control of difficult to detect radionuclides 369 definition of nonradioactive 366 guidance for release 371 process for control 366–367 surface contamination standards 369–371 waste management 367–369 Cooling systems 27 Counter telescopes 316 Critical energy 41–42, 49 Danger parameter 141–145 Decay length 99 Definitions (see Glossary) Detectors 272–316 activation detectors 280–281, 282 active 291–299, 312 bubble detectors 289–290 counter telescopes 316 direct assessment of dose equivalent 310 direct assessment of quality factor 310 fission counters 297–299 for above and below 20 MeV 277 Geiger-Mueller counters 275–276, 314 ionization chambers 273–275, 313–314, 315 linear-energy transfer (LET) spectrometry 308–309 moderated detectors 285, 287, 291–297 neutron detectors 276–304, 312–313, 315–316 neutron spectrometry 299–304 nuclear emulsions 279–280 passive 277–290 proton-recoil counters 303–304 recombination chambers 305–307 resolving time 272–273 silicon detectors 316 spectrometry 299–304 spectrum-unfolding methods 301–303 thermoluminescence dosimeters 276–279, 312–313, 315, 316 threshold 281, 283–285 tissue-equivalent proportional counters 307–308 track-etch detectors 287–289 Diffusion equation 152 Distributed losses 204–213 definition 204 generalized loss model 212–213 photon shielding experiments 208–212 synchrotron facilities 205–208 Door shielding design 267–268 Dose equivalent 310 direct assessment 310 Dose equivalent (Moyer model) 219–222 Dose equivalent, skyshine 329–330, 332–334 Dose limits 270–271, 305 Dosimetry considerations 269–273 considerations specific to particle accelerators 272–273 detector resolving time 272–273 dose limits 270–271 need for 269 quality factor 270–271 Duty factor 17, 272 Earth shield radioactivation 348–352 EGS4 code system 156 Electromagnetic cascade 65–66, 68, 197–198 concepts and units 66 energy deposition 68 Moliere length 66 INDEX Electron accelerators (1 to 100 MeV), neutron shielding 195–197 Electron accelerators (1 to 100 MeV), photon shielding 188–195 barriers 191–194 leakage radiation 194 occupancy factor 191 operating conditions 188–189 scattered photons 194–195 source terms 189–191 use factor (orientation) 191 workload 190 Electron accelerators (Ͼ100 MeV), shielding 197–213 distributed losses 204–213 electromagnetic cascade 197–198 generalized loss model 212–213 neutrons 198–213 photon shielding experiments 208–212 synchrotron facilities 205–208 Environmental impact from radioactivation products 347, 352–355 Environmental monitoring 311–319 external exposure 311 muon measurement 315–317 neutron measurement 312–313 photon measurement 313–315 prompt radiation 311 radioactive aerosols 319 radioactive emissions in air 317–319 radioactive gas 317–319 recycled radioactivity 312 Environmental pollution 321 gases and water 321 solids 321 Environmental radiological aspects 320–359 environmental pollution 321 induced radioactivity 320, 337–357 prompt radiation 320 / 491 radioactivity produced in earth shielding and ground water 348–355 radiolysis in water and air 357–359 skyshine 321–337 transfer of radioactivity 355–357 Evaporation neutrons 80, 215–216 Exothermic reactions 116 Facility design for radiation safety 362–365 access and egress 362–363 Fission counters 297–299 cross sections 297–298 fission chambers 299 fission reactions 297 materials used 297 Fluence 37–39 FLUKA code 157 Forward spike 51 Gas monitors 317–319 General specifications and parameters 28 Geiger-Mueller counters 275–276, 314 resolving time 276 Hadronic (nuclear) cascade 101–103 Hadronic cascade Ͼ3 GeV 232–239 analytical methods 232–236 Monte-Carlo methods 236–239 Hadron yields, total 91 Half-value layer (photon) 163 Heavy ion acceleration 118–132 specific energy 118 range versus energy 118–119 neutron angular distributions 120–132 neutron yield 118–132 High-voltage supplies 25–27 Historical review 13–17 492 / INDEX Importance 152–153 concept of 153 values of in Appendix A 152 Importance functions 328–329, 332, 373–389 tables for neutrons and photons (Appendix A) 373–389 Induced radioactivity 320–321, 337–357 Induced radioactivity in air 338–348 collective exposure 347–348 gaseous releases from water 347 impact on environment 347 photoactivation 340–342 produced directly in air 338–340 produced in dust 346–347 quantity released 345–346 spallation, high energy neutron activation 343–346 thermal neutron capture 341, 343 Integrated Tiger Series code 158 Intranuclear cascade 215–216 Ion and electron sources 18 Ionization chambers (see also recombination chambers) 273–275, 313, 315 for dose determination 273–274 practical problems 274 pulsed radiation fields 274 radiofrequency (RF) interference 274 small beam cross sections 275 volume recombination 275 Kinematic relations, special relativity (Appendix B) 390–404 analytical equations 390–391 data for 13 charged particles 392–404 Labyrinth shielding, neutrons 259–266 curved tunnels 266 universal neutron transmission curves 260–261 Labyrinth shielding, photons 257–258 Labyrinth shielding, photons and neutrons 258–259 Leakage radiation 194 Linear-energy transfer (LET) 308–310 Light ion acceleration 113–118 neutron angular distribution 115–116 neutron yield based on proton acceleration 113–117 Livingston plot 15–16 MARS code 156 Maxwellian energy spectrum 61 Measurements (see Radiation measurements) Method of discrete ordinates 152 Method of moments (sphericalharmonics method) 152 Microwave supplies 25–27 Mixed-field dosimetry 304–311 direct assessment of quality factor and dose equivalent 310 drawbacks in techniques 304 linear-energy transfer (LET) spectrometry 308–309 recombination chambers 305–307 tissue-equivalent proportional counters 307–308 MCNP code 158 Moderated detectors 285, 287, 291–297 accelerator duty cycle and moderation time 294–297 energy response 292 long counter 293–294 moderators 291 rem meters 292–293 Moliere length (radius) 57, 198 Monitoring of radioactive material 366–371 Monte-Carlo method 154–156 INDEX MORS-CGA code 158 Moyer model 218–232 angular relaxation parameter 223–224 attenuation parameter 222–223 buildup factor 219 cascade propagators 221 determination model parameter 222–226 effectiveness and limitations 229–232 generalized formulation, dose equivalent 219–222 introduction 218–219 practical examples 226–229 source strength parameter 224–226 Moyer model, practical examples 226–229 finite uniform line source 228–229 infinite uniform line source 227–228 point source 226–227 MUCARLO code 159 MUON89 code 160 Muon measurement, environment 315–317 counter telescopes 316 ionization chambers 315 miscellaneous detectors 317 nuclear emulsions 316 silicon detectors 316 thermoluminescence dosimeters 316–317 Muon production at electron accelerators 62–70 dose rate 65 electromagnetic cascade 65–70 electron accelerators 62–65 fluence rate 64 Muon production at proton accelerators 98–101 Muon shielding 239–242 MUSTOP code 159 Neutron detectors 272–304, 312–313, 315–316 / 493 active 291–299, 312 bubble detector 289–290 counter telescopes 316 fission counter 297 for above and below 20 MeV 277 ionization chambers 273–275, 313–314, 315 moderated detectors 285, 287, 291–297 passive 277–290 resolving time 272–273 silicon detectors 316 spectrometry 299–304 thermoluminescence dosimeters 276–279, 312–313, 315, 316 track etch detectors 287–288 Neutron dosimetry 276–304 Neutron measurement, environment 312–313 moderated counters, active 312 thermoluminescence dosimeters 312–313 Neutron production at electron accelerators 60–62, 174, 201 high energy 201 photoneutron production 59, 174 photopions 61 quasi-deuteron production 61 Neutron production at positive ion accelerators 113–132 light ions 113–118 heavy ions 118–132 Neutron production at proton accelerators 73–98, 105–112 angular distributions at high energies 80–98 angular distributions at low energies 74–80 at high energies 80–98 at intermediate energies 80 at low proton energies 74–80 energy spectra 105–112 (p,n) reactions 74–80 yields at high energies 80–98 yields at low energies 74–80 Neutron shielding 195–197 494 / INDEX Neutron skyshine 323–331, 334–337 analytical expression based on measurements 324–327 based on diffusion theory (Ͻ20 MeV) 323–324 collective exposure 336–337 comparison of different calculations 334–336 computer methods for source term and transport in air 327–328 dose equivalent based on combined analytical and experimental data 329, 330 effective attenuation length in air 324, 327 importance functions for dose equivalent calculations 328–329, Appendix A Neutron spectrometry 299–304 Bonner spheres 299–301 proton recoil counters 303–304 spectrum unfolding methods 301–303 Neutron transmission 167–178 broad beam 169–172 methods of discrete ordinates and Monte Carlo 169–172 production and transport 173–175 tenth-value layer 173–177 Nitrogen oxides 357–359 NMTC/HETC code 157 Nonradiation hazards 365 Nuclear cascade (see Hadronic cascade) Nuclear emulsions 279–280 Occupancy factors 183–185, 191 Operational radiation safety programs (see Radiation safety program) Organization for radiation safety 360–362 conflicts of interest 361 contribution to design and operation 361 relation to whole accelerator facility 361 safety committee 362 staff responsibilities 361 Oxides of nitrogen 357–359 Ozone 357–359 Particle accelerator auxiliary systems 25–27 high-voltage supplies 25–27 microwave power supplies 25–27 Particle accelerators 12–32 accelerating schemes 19–23 applications 14, 28 beam delivery systems 23 beam stops 24 classification 12 cooling systems 27 definitions 812 future developments 29 general specifications and parameters 28 historical review 13–17 ion and electron sources 18 operating energies 15–17 radiation produced 14–15, 17 siting and layout 29–32 vacuum systems 27 Personnel security for radiation safety 365–366 complexity of facility operation 365–366 conversion to digital control 366 Photon accelerators, transverse shielding 213–232 energies Ͻ3 GeV 216–218 energies Ͻ3 GeV 218–232 PHOTON code 160 Photon measurement, environment 313–315 Geiger–Mueller counters 314 ionization chambers 313–314 thermoluminescence dosimeters 315 Photon shielding 188–195 INDEX Photon skyshine 328–329, 331–334, 336–337 collective exposure 336–337 comparison of different calculations 336 dose equivalent, analytical relationship 333–334 dose equivalent, empirical relationship 332–333 importance functions 328–329, 332, Appendix A Photon transmission 161–167 attenuation length 162 half-value layer 163 point kernel equations 161–163 practical data 164–167 primary particles 73 tenth-value layer 163, 164 transmission factor 162 Prompt radiation in environment 312–317, 320 muon measurement 315–317 neutron measurement 312–313 photon measurement 313–315 Proton accelerators, forward shielding 232–242 hadronic cascade Ͼ3 GeV 232–239 muons 239–242 proton energies Ͻ3 GeV 232 Proton accelerators (Ͻ3 GeV), transverse shielding 213–232 attenuation length 217–218 calculational formalism 216 energies Ͻ3 GeV 216–218 energies Ͼ3 GeV 218–232 Proton accelerators (Ͼ3 GeV), transverse shielding 218–232 Moyer model 218–232 Proton accelerators, transverse shielding 103–105, 214–216 evaporation neutrons 215–216 intranuclear cascade 215–216 proton-nucleus interaction particle yields 214–216 radiation environment 103–105 Proton-nucleus interaction particle yields 214–216 / 495 evaporation neutrons 215–216 intranuclear cascade 215–216 Proton-recoil counters 303–304 Quality factor 270–271, 306–307, 310 direct assessment 310 Radiation length 42–43 Radiation measurement 269–319 activation detectors 280–281, 282 bubble detectors 289–290 characterization of radiation environment versus single scalar quantity 319 direct assessment of dose equivalent 310 direct assessment of quality factor 310 direct assessment of quality factor and dose equivalent 310 dosimetry considerations 269–271 environmental monitoring 311–319 fission counters 297–299 Geiger-Mueller counters 275–276 ionization chambers 273–275 linear-energy transfer (LET) spectrometry 308–309 mixed-field dosimetry 304–311 moderated detectors 285, 287, 291–297 neutron dosimetry detectors 276–304 neutron spectrometry 299–304 nuclear emulsions 279–280 proton-recoil counters 303–304 radioactive gas monitors 317–319 recombination chambers 305–307 spectrum-unfolding methods 301–303 496 / INDEX thermoluminescence dosimeters 276–279 threshold detectors 281, 283–285 tissue-equivalent proportional counters 307–308 track-etch detectors 287–289 universal dose-equivalent instruments 310–311 Radiation produced 14–15 Radiation production at accelerators by radioactivation 132–145 high-energy particles 136–145 low-energy particles 133–136 Radiation production at accelerators of positive ions 112–132 heavy ions 118–132 light ions 113–118 Radiation production at electron accelerators 39–69 bremsstrahlung 43–49 electron beams 40–41 muons 62–65 neutrons 59–62 photon fields 43–59 Radiation production at proton accelerators 70–112 hadronic cascade 101–103 kaons 98–101 muons 98–101 neutrons at high energies 80–98 neutrons at intermediate energies 80 neutrons at low energies 74–80 neutron spectra external to shielding 108–112 neutron spectra internal to shielding 105–108 neutron spectral environment 103–112 neutron yields 73 pions 98–101 (p,n) reactions 74–80 proton beams 73 Radiation protection goals 183–184 Radiation safety 7–10, 14–15 advisory organizations federal regulation international agencies local regulation national organizations 10 protection standards 10 radiation produced 14–15 regulatory and advisory agencies state regulation Radiation safety program 360–372 access and egress 362–363 conflicts of interest 361 contribution to design and operation 361 control of radioactive material 366–367 elements of an operational program 360 facility design 362–365 guidance for release of radioactive material 371 monitoring and control 366–371 nonradiation hazards due to facility and equipment complexity 365 organization 360–362 personnel security 365–366 radioactive waste management 367–369 relation to whole accelerator facility 361 safety committee 362 specific program elements for accelerators 360–372 staff responsibilities 361 surface contamination standards 369–371 training 371–372 ventilation 364–365 warning needs 365–366 Radiation shielding (see Shielding) INDEX Radiation sources 33–145 angular and energy distribution 35 definition and introduction 33–35 electron accelerators 39–69 general considerations 35–39 hadronic cascade 101–103 muons 98–101 neutrons 70–98 neutron spectra 103–112 production of secondary particles 35–39 proton accelerators 70–112 radiations of concern 34 relation to radiation protection 35–39 Radiation transport theory 148–154 Radioactivation 132–145 danger parameter for calculating absorbed dose rate 141–145 multiple reactions from highenergy particles 136–139 simple rules for estimating radioactivity 139–141 thick-target yields by lowenergy particles 133–136 Radioactivation at accelerators 132–145 Radioactivation, radiation safety concerns 363–364 choice of materials 363 engineering planning and design 364 Radioactive aerosols 319 Radioactive gas monitors 317–319 Radioactive waste management 367–369 exposure to workers and public 367 inventory system 367–368 storage and shipping 368–369 Radioactivity induced in air (see Induced radioactivity in air) / 497 Radioactivity produced in accelerator materials 138 Radioactivity produced in earth shielding and ground water 348–361 assessment categories 348–349 collective exposure 352–361 drinking contaminated water 353–355 environmental impact 352–355 examples of radionuclide concentration calculation 350–352 identified radionuclides 349 ingestion 353 inhalation 355 radionuclide concentration calculation 349–352, 352–355 Radiolysis in water and air 357–359 analytical calculation for ozone 358–359 production of ozone and nitrogen oxides 357–358 threshold limit values 359 Radionuclides activated in earth and ground water 348–352 Ranges (see Stopping power) Recombination chambers 305–307 quality factor relation to chamber current 306–307 types of recombination 305 use 264 Reflection coefficient (see Albedo) Regulatory and advisory agencies 7–10 Removal cross sections 175 Rules of thumb 44–49, 139–143, 256 Safety program (see Radiation safety program) Scattered photons, electron accelerators 194–195 Scattering—Albedo 178–179 Scatter paths 179 Secondary radiation 18 498 / INDEX Secondary particle yields (general) 35–39 SHIELD11 code 160 Shielding 146–268 angular fluence 148–150 angular fluence and radiation protection quantities 148 Boltzmann equation, approximate solutions and comparisons 152–154 Boltzmann equation, construct 150–151 computer calculation codes 154–161 concept of importance 153 door design 267–268 design factors 147 design stages 147 electron accelerators (1 to 100 MeV) 188–197 electron accelerators (Ͼ100 MeV) 197–213 muons 239–242 proton accelerators, forward shielding 232–242 proton accelerators, transverse shielding 213–232 proton accelerators (Ͻ3 GeV), transverse shielding 216–218 proton accelerators (Ͼ3 GeV), transverse shielding 218–232 radiation transport theory 148–154 shielding materials 242–255 tunnels, labyrinths and ducts 255–268 Shielding materials 242–255 concrete 244–246 earth 243–244 factors for selection 242–243 high atomic-number materials 252–254 low atomic-number materials 254 other hydrogenous materials 246–249 special considerations 254–255 steel 249–252 Shielding, practical design 161–188, 226–229 ALARA (as low as reasonably achievable) 183–184 area occupancy 184–185 attenuation length 162 beam-loss source terms, determination 185–188 beam-loss source terms, specification 185–188 broad-beam transmission 169–172 half-value layer 163 methods of discrete ordinates and Monte-Carlo for neutrons 169–172 neutron production and transport 173–175 neutron transmission 167–178 photon transmission 163–167 point kernel equations 161–163 practical data for photon transmission 164–167 practical shield design 161, 226–229 radiation protection goals 183–184 scatter paths 179, 183 scattering—Albedo 178–179 tenth-value layer for photons 163 tenth-value layer for neutrons 173–177 transmission factor 162 use factors 184–185 Shower maximum 57 Siting and layout considerations 29–32 Skyshine 312, 320–337, 347–348 comparison of different calculations 334–336 definition 320 demonstration of existence and neutron dominance 321–323 neutrons 323–331 photons 331–334 population collective exposure 336–337, 347–348 INDEX SKYSHINE III code 161 SKYSHINE-KSU code 161 Sources of radiation (see Radiation sources) Source strength parameter 224–226 Source terms, electron accelerators 189–191 Specific energy 118 Spectrum-unfolding methods 301–303 analytical (Fredholm equation) 301–302 codes for discrete 303 discrete 302–303 STAC8 code 160 Stopping power 39, 113, 118 Stray particles 18 Superconducting materials 17 Synchrotron radiation facilities 205–208 Tenth-value layer (photon) 163 Thermoluminescence dosimeters 276–279 for neutrons 277–279 for personnel 276 LiF and 7LiF 278 response with linear-energy transfer (LET) 278–279 variability 278 Threshold reactions, detectors 84, 126, 281, 283–285 characteristics 283 cross sections 283, 285 nuclear reactions 282 use 84, 126 Threshold limit values, ozone and nitrogen oxides 359 TOMCAT code 159 / 499 Track-etch detectors 287–289 Training for radiation safety 371–372 Transfer of radioactivity 355–357 causes 355–356 examples that exacerbate transfer 356–357 TRIPOLI code 161 Tunnels, labyrinths and ducts 255–268 door design 267–268 general and two rules 255–256 labyrinths for neutrons 259–265 labyrinths for neutrons, curved 266 labyrinths for photons 257–258 tunnels for photons and neutrons 258–259 universal neutron transmission curves 260–261 Tunnel shielding, curved, for neutrons 266 Tunnel shielding, photons and neutrons 258–259 Use factors 184–185, 161 Yields, particle yields 35 Vacuum systems 27 Ventilation, radiation safety concerns 364–365 competing needs 365 radioactivity and toxic gases 364–365 Waste management (see Radioactive waste management) Workload 190 .. .NCRP Report No 144 Radiation Protection for Particle Accelerator Facilities Recommendations of the NATIONAL COUNCIL ON RADIATION PROTECTION AND MEASUREMENTS Issued... specific radiological protection issues at particle accelerators: NCRP Report No 72, Radiation Protection and Measurements for Low-Voltage Neutron Generators and NCRP Report No 79, Neutron Contamination... information contained in this Report useful Since 1977, NCRP has issued two reports that discuss specific radiological -protection issues at particle accelerators: NCRP Report No 72, Radiation Protection