NCRP report no 119 a practical guide to the determination of human exposure to radiofrequency fields

NCRP REPORT No 119 A PRACTICAL GUIDE TO THE DETERMINATION OF HUMAN EXPOSURE TO RADIOFREQUENCY FIELDS Recommendations of the NATIONAL COUNCIL O N RADIATION PROTECTION AND MEASUREMENTS Issued December 31,1993 National Council on Radiation Protection and Measurements 7910 Woodmont Avenue 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 reports 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 prwess disclosed in this Report, under the Civil Rights Act of 1964, Section 701 et seq as amended 42 U.S.C Sectwn 2000e et seq (Title VZI) or any other statutory or common law theory governing liability Library of Congress Cataloging-in-PublicationData National Council on Radiation Protection and Measurements A practical guide to the determination of human exposure to radiofrequency fields : recommendations of the National Council on Radiation Protection and Measurements cm.-(NCRP report ; no 119) p "Issued December 31, 1993." Includes bibliographical references and index ISBN 0-929600-35-5 Radio waves-Health aspects Radiation dosimetry I Title 11 Series [DNLM: Radio Waves Radiation Protection-standards Radiation Dosage WD 605 N277p 19931 RA569.3.N375 1993 612'.01448-dc20 DNLMIDLC for Library of Congress 93-45910 CIP Copyright National Council on Radiation Protection and Measurements 1993 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 Preface This Report is the third in a series ofNational Council on Radiation Protection and Measurements (NCRP) reports concerning radiofrequency electromagnetic (RFEM) radiation which constitutes an extension of NCRP interest in the subject of nonionizing radiation The first report, NCRP Report No 67, Radiofrequency Ebctromagnetic Fields-Properties, Quantities and Units, Biophysical I n t e n tion, and Measurements, dealt primarily with quantities and units associated with RFEM fields The second report, NCRP Report No 86, Biological Effectsand Exposure Criteria for Radiofrequency Electromagnetic Fields, dealt primarily with the biological effects of such fields This, the third report in the series, addresses the practical measurement of RFEM fields This Report was prepared by Scientific Committee 89-2 on Practical Guidance on the Evaluation of Human Exposures to Radiofrequency Radiation (formerly Scientific Committee 78) Serving on the Committee were: Richard A Tell, Chairman Richard Tell Associates, Inc Las Vegas, Nevada Howard I Bassen Center for Devices and Radiological Health Rockville, Maryland Members David L Conover National Institute for Occupational Safety and Health Robert A Taft Laboratories Cincinnati, Ohio Jules Cohen Carl H Durney Jules Cohen and Associates University of Utah Washington, D.C Salt Lake City, Utah Ronald C Petersen AT&T Bell Laboratories Murray Hill, New Jersey iv PREFACE NCRP Secretariat Thomas M Koval, Scientific Stuff Assistant (1983-88) William M Beckner, Scientific Staff Assistant (1988-93) Cindy L O'Brien, Editorial Assisant The Council wishes to express its appreciation to the Committee members for the time and effort devoted to the preparation of this Report Charles B Meinhold President, NCRP Bethesda, Maryland December 1,1993 Contents Preface iii Introduction 1.1 The Study of Radiofrequency Hazards 1.2 The Radiofrequency Spectrum 1.3 The Increasingly Crowded Radiofrequency Spectrum 1.4 The Interaction of Radiofrequency Energy with Tissues 1.5 Environmental Aspects 1.6 The State of Radiofrequency Safety Standards 1.7 Public Awareness 1.8 Overview of this Report Basic Concepts 2.1 Explanation of Terms and Units 2.1.1 Glossary 2.1.2 Units 2.1.3 Vectors 2.2 Electromagnetic Fields 2.2.1 Electric Fields 2.2.2 Magnetic Fields 2.2.3 Static Fields 2.2.3.1 Static-Electric Fields 2.2.3.2 Static-Magnetic Fields 2.2.4 Quasi-Static Fields 2.2.5 Interaction of Fields with Materials 2.2.5.1 Nonmagnetic Materials 2.2.5.2 Permittivity 2.2.5.3 Energy Absorption 2.2.5.4 Electric-Flux Density 2.2.5.5 Magnetic Materials 2.2.6 Wave Propagation 2.2.6.1 Modulation 2.2.6.2 Amplitude Modulation 2.2.6.3 Frequency Modulation 2.2.6.4 Spherical Waves 2.2.6.5 Plane Waves 2.2.7 Near Field vi I CONTENTS 2.2.8 Far Field 2.2.9 Interaction of Fields with Objects 2.2.9.1 Planar Conductors 2.2.9.2 Planar Dielectrics 2.2.9.3 Standing-Wave Ratio 2.2.9.4 Nonplanar Objects 2.2.10 Poynting's Theorem (Power-Conservation Theorem) 2.2.11 Antennas 2.2.11.1 Near and Far Fields 2.2.11.2 Radiation Patterns 2.3 Dosimetry 2.3.1 Electrical Properties of Tissue 2.3.2 Plane-Wave Absorption as a Function of Frequency 2.3.2.1 Planar Models 2.3.2.2 Other Models 2.3.3 Polarization 2.3.4 Specific Absorption Rate Characteristics 2.3.5 Dosimetry Concepts as Applied to Radiofrequency Protection Guides 2.4 Concepts of Measurements 2.4.1 Electric Field Measurements 2.4.2 Magnetic Field Measurements 2.4.3 Specific Absorption Rate Measurements 2.5 Generalizations and Frequently Used Relationships Procedures for Evaluation of Exposure 3.1 General Objectives 3.2 Protection Guide Criteria 3.2.1 Single-Value Protection Guide 3.2.2 Frequency-Dependent Protection Guide 3.3 Data Necessary for Exposure Evaluation 3.3.1 Frequency Spectrum Coverage 3.3.2 Variability with Time 3.3.3 Near- Versus Far-Field Conditions 3.3.4 Probe Characteristics 3.3.5 Time and Spatial Averaging 3.3.6 Effects of Secondary Sources 3.3.7 Uncertainty Factor 3.4 Data Analysis and Exposure Evaluation 3.4.1 Limited Area Survey 3.4.2 Area Survey CONTENTS vii Instruments and Measurement Techniques 77 4.1 Introduction 77 4.1.1 Broadband Survey Meters 78 4.1.1.1 Desirable Characteristics of Broadband Survey Instruments 86 4.1.1.1.1 Isotropic response 86 4.1.1.1.2 Frequency response 86 4.1.1.1.3 Absolute accuracy 87 4.1.1.1.4 Out-of-band response 88 4.1.1.1.5 Dynamic range 88 4.1.1.1.6 Meter output units 89 4.1.1.1.7 Response to the parameter being measured 89 4.1.1.1.8 Electromagnetic interference 89 4.1.1.1.9 Probe burnout alarm 90 4.1.1.1.10 Probe overload/burnout rating 90 4.1.1.1.11 Peak hold 90 4.1.1.1.12 Static-charge sensitivity 90 4.1.1.1.13 Battery operation 91 4.1.1.1.14 Response time 91 4.1.1.1.15 Stability 91 4.1.1.1.16 Spatial resolution of the instrument 91 4.1.1.1.17 Multiple signal addition 92 4.1.1.1.18 Modulation response 92 4.1.1.1.19 Readability 92 4.1.1.1.20 Ease of adjustment and use 92 4.1.1.1.21 Portability 92 4.1.1.1.22 Durability 92 4.1.1.1.23 Recorder output 92 4.1.1.1.24 Response to other environmental factors 92 4.1.1.2 Peripheral Equipment for Broadband Survey Instruments 93 4.1.2 Narrowband Systems 93 4.1.2.1 Antenna Types 94 4.1.2.2 Spectrum Analyzers 101 4.1.2.3 Field-Strength Meter 106 4.1.2.4 Automated Measurement Systems ; 110 4.1.3 Quasi-Narrowband Systems 117 4.2 General Measurement Techniques and Pitfalls 120 4.2.1 Characterizing the Source 120 4.2.2 Leakage Fields 122 4.2.3 Antenna Fields 126 4.2.4 Precautions for Ensuring Measurement Accuracy 127 128 129 4.2.5 Precautions for Protection of the Operator 4.3 Special Measurements Recommended Areas for Further Research and Technical or Engineering Development 131 Appendix A Hazard Evaluation Procedures for Common Sources 133 A.1 Amplitude-Modulation Radio Broadcast 133 A.2 Frequency-Modulation Radio Broadcast 136 A.3 Very-High-Frequency and Ultra-High-Frequency Television Broadcast 139 A.4 Terrestrial Microwave Radio (Point-to-Point Radio Relay) 142 A.5 Satellite Communication-Earth Stations 144 A.6 Hand-Held Portable Radios (Including Cordless and Hand-Held Cellular Telephones) 147 A.7 Mobile Radios (Vehicle Mounted-Including Citizens Band and Cellular Radios) 149 A.8 Diathermy Equipment (Microwave and Shortwave) 151 A.9 Electrosurgical and Electrocautery Units 153 A.10 Hyperthermia Equipment 155 A l l Magnetic Resonance Imaging Systems 157 A.12 Radar 158 A.13 Marine Radar .163 A.14 Police and Sports Radar 165 A.15 Microwave Industrial HeatingIDrying Equipment 166 A.16 Radiofrequency Induction Heaters 168 A.17 Radiofrequency Dielectric Heaters (Heat Sealers) 171 A.18 Anti-Theft Devices 174 A.19 Microwave Door Openers 176 A.20 Microwave Intrusion Alarms 177 A.21 Microwave Ovens 178 A.22 Visual-Display Terminals 180 A.23 LORANIOMEGA Navigational Stations 184 Appendix B Radiofrequency Exposure Determination: Examples 186 B.l Radiofrequency Dielectric Heater Exposure Survey: A Sample Problem 186 B.2 Point-to-Point Microwave Radio: A Sample Problem 188 CONTENTS / ix B.3 Amplitude-Modulation Radi.0 A Sample Problem 194 B.4 Multiple Frequency-Modulation Radio: A Sample Problem 196 References 200 The NCRP 209 NCRP Publications 217 Index 229 Introduction 1.1 The Study of Radiofrequency Hazards The study of radiofrequency (RF) hazards is a relatively new area of investigation in the United States Engineering analyses of potential electromagnetic (EM) radiation exposure environments and the absorption of this energy by humans, animals, and synthetic human and animal models (phantoms) have become necessary due to the proliferation and distribution of sources of RF energy in the workplace and the environment Also, developmentsin this new technical area have been stimulated by both the formulation of safety guidelines and standards against which radiation exposure can be judged and a continually increasing public awareness and concern over the possibility of health hazards from exposure to RF radiation Engineering measurement surveys and analyses of external RF fields can provide insight needed for the determination of the potential safety or danger associated with a particular exposure situation Several United States and foreign documents have been written on the subject of evaluation of RF hazards (most notably: ANSY IEEE, 1992a; Kulikovskaya, 1970; Marha et al., 1971; 1981; Mastrantonio and Russo, 1989; Minin, 1974) There has existed for some time a need for a guide in the form of a compendium of general knowledge useful to those health and safety professionals concerned with evaluating RF hazards However, there is no single reference manual or guide designed for use by environmental health and safety personnel who are not electrical engineers or physicists specializing in EM measurements This Report, A Practical Guide to the Determination of Human Exposure to Radiofrequency Fields, has been prepared to fill this void It is a handbook for guiding those responsible for the evaluation of RF and microwave hazards This Report is designed to give practical information on how to evaluate RF exposure, i.e., the physical characterization of EM fields This Report provides a comprehensive collection of information on various RF radiation sources, and a straight-forward "how-to" guide for estimating the exposure associated with these sources by providing a framework ("cookbook") for health and safety personnel to assess individual sources of RF and microwave radiation It is 218 / NCRP PUBLICATIONS Alpha-Emitting Particles in Lungs (1975) Tritium Measurement Techniques (1976) Structural Shielding Design and Evaluation for Medical Use of X Rays and Gamma Rays of Energies Up to 10 MeV (1976) Environmental Radiation Measurements (1976) Radiation Protection Design Guidelines for 0.1 -100 MeV Particle Accelerator Facilities (1977) Cesium-137 from the Environment to Man: Metabolism and Dose (1977) Medical Radiation Exposure of Pregnant and Potentially Pregnant Women (1977) Protection of the Thyroid Gland i n the Event of Releases of Radioiodine (1977) Instrumentation and Monitoring Methods for Radiation Protection (1978) A Handbook of Radioactivity Measurements Procedures, 2nd ed (1985) Operational Radiation Safety Program (1978) Physical, Chemical, and Biological Properties of Radiocerium Relevant to Radiation Protection Guidelines (1978) Radiation Safety Training Criteria for Industrial Radiography (1978) Tritium in t h Environment (1979) Tritium and Other Radionuclide Labeled Organic Compounds Incorporated i n Genetic Material (1979) Influence of Dose and Its Distribution in Time on DoseResponse Relationships for Low-LET Radiations (1980) Management of Persons Accidentally Contaminated with Radionuclides (1980) Radiofrequency Electromagnetic Fields-Properties, Quantities and Units, Biophysical Interaction, and Measurements (1981) Radiation Protection in Pediatric Radiology (1981) Dosimetry of X-Ray and Gamma-Ray Beams for Radiation Therapy i n the Energy Range 10 keV to 50 MeV (1981) Nuclear Medicine-Factors Influencing the Choice and Use of Radionuclides in Diagnosis and Therapy (1982) Operational Radiation Safety-Training (1983) Radiation Protection and Measurement for Low-Voltage Neutron Generators (1983) Protection in Nuclear Medicine and Ultrasound Diagnostic Procedures in Children (1983) NCRP PUBLICATIONS / 219 Biological Effects of Ultrasound: Mechanisms and Clinical Implications (1983) Iodine-129: Evaluation of Releases from Nuclear Power Generation (1983) Radiological Assessment: Predicting the Transport, Bioaccumulation, a n d Uptake by M a n of Radionuclides Released to the Environment (1984) Exposures from the Uranium Series with Emphasis on Radon and Its Daughters (1984) Evaluation of Occupational and Environmental Exposures to Radon and Radon Daughters in the United States (1984) Neutron Contamination from Medical Electron Accelerators (1984) Induction of Thyroid Cancer by Ionizing Radiation (1985) Carbon-14 in the Environment (1985) SI Units in Radiation Protection and Measurements (1985) The Experimental Basis for Absorbed-Dose Calculations in Medical Uses of Radionuclides (1985) General Concepts for the Dosimetry of Internally Deposited Radionuclides (1985) Mammography-A User's Guide (1986) Biological Effects and Exposure Criteria for Radiofrequency Electromagnetic Fields (1986) Use of Bioassay Procedures for Assessment of Internal Radionuclide Deposition (1987) Radiation Alarms and Access Control Systems (1986) Genetic Effects from Znternally Deposited Radionuclides (1987) Neptunium: Radiation Protection Guidelines (1988) Public Radiation Exposure from Nuclear Power Generation in the United States (1987) Ionizing Radiation Exposure of the Population of the United States (1987) Exposure of the Population in the United States and Canada from Natural Background Radiation (1987) Radiation Exposure of the U.S Population from Consumer Products and Miscellaneous Sources (1987) Comparative Carcinogenicity of Ionizing Radiation and Chemicals (1989) Measurement of Radon and Radon Daughters in Air (1988) Guidance on Radiation Received i n Space Activities (1989) Quality Assurance for Diagnostic Imaging (1988) Exposure of the U.S Population from Diagnostic Medical Radiation (1989) 220 NCRP PUBLICATIONS 101 Exposure of the U.S Population from Occupational Radiation (1989) 102 Medical X-Ray, Electron Beam and Gamma-Ray Protection for Energies Up to 50 MeV (Equipment Design, Performance and Use) (1989) 103 Control of Radon in Houses (1989) 104 The Relative Biological Effectiveness ofRudiations ofDifferent Quality (1990) 105 Radiation Protection for Medical and Allied Health Personnel (1989) 106 Limit for Exposure to "Hot Particles" on the Skin (1989) 107 Implementation of the Principle of As Low As Reasonably Achievable (ALARA) for Medical and Dental Personnel (1990) 108 Conceptual Basis for Calculations of Absorbed-Dose Distributions (1991) 109 Effects of Ionizing Radiation on Aquatic Organisms (1991) 110 Some Aspects of Strontium Rudiobiology (1991) 111 Developing Radiation Emergency Plans for Academic, Medical or Industrial Facilities (1991) 112 Calibration of Survey Instruments Used in Radiation Protection for the Assessment of Ionizing Radiation Fields and Radioactive Surface Contamination (1991) 113 Exposure Criteria for Medical Diagnostic Ultrasound:I Criteria Based on Thermal Mechanisms (1992) 114 Maintaining Radiation Protection Records (1992) 115 Risk Estimates for Radiation Protection (1993) 116 Limitation of Exposure to Ionizing Radiation (1993) 117 Research Needs for Radiation Protection (1993) 118 Radiation Protection i n the Mineral Extraction Industry (1993) 119 A Practical Guide to the Determination of Human Exposure to Radiofrequency Fields (1993) Binders for NCRP reports are available Two sizes make it possible to collect into small binders the "old series" of reports (NCRP Reports Nos 8-30) and into large binders the more recent publications (NCRP Reports Nos 32-119) Each binder will accommodate from five to seven reports The binders carry the identification "NCRP Reports" and come with label holders which permit the user to attach labels showing the reports contained in each binder The following bound sets of NCRP reports are also available: Volume I Volume 11 NCRP Reports Nos 8,22 NCRP Reports Nos 23, 25, 27, 30 NCRP PUBLICATIONS Volume 111 Volume IV Volume V Volume VI Volume VII Volume VIII Volume IX Volume X Volume XI Volume XII Volume XIII Volume XIV Volume XV Volume XVI Volume XVII Volume XVIII Volume XIX Volume XX Volume XXI Volume XXII Volume XXIII 221 NCRP Reports Nos 32,35,36,37 NCRP Reports Nos 38,40,41 NCRP Reports Nos 42,44,46 NCRP Reports Nos 47,49,50,51 NCRP Reports Nos 52,53,54,55,57 NCRP Report No 58 NCRP Reports Nos 59,60,61,62,63 NCRP Reports Nos 64,65,66,67 NCRP Reports Nos 68,69,70,71,72 NCRP Reports Nos 73,74,75,76 NCRP Reports Nos 77,78,79,80 NCRP Reports Nos 81,82,83,84,85 NCRP Reports Nos 86,87,88,89 NCRP Reports Nos 90,91,92,93 NCRP Reports Nos 94,95,96,97 NCRP Reports Nos 98,99,100 NCRP Reports Nos 101,102,103,104 NCRP Reports Nos 105,106,107,108 NCRP Reports Nos 109,110,111 NCRP Reports Nos 112,113,114 NCRP Reports Nos 115,116,117,118 (Titles of the individual reports contained in each volume are given above.) No NCRP Commentaries Title Krypton-85 in the Atmosphere-With Specific Refemnee to the Public Health Significance o f the Proposed Controlled Release at Three Mile Island (1980) Preliminary Evaluation of Criteria for the Disposal of Transuranic Contaminated Waste (1982) Screening Techniques for Determining Compliance with Environmental Standards-Releases of Radionuclides to the Atmosphere (1986),Revised (1989) Guidelines for the Release of Waste Water from Nuclear Facilities with Special Reference to the Public Health Significance of the Proposed Release of Treated Waste Waters at Three Mile Island (1987) Review of the Publication, Living Without Landfills (1989) Radon Exposure o f the U.S Population-Status o f the Problem (1991) NCRP PUBLICATIONS Misadministration of Radioactive Material in MedicineScientific Background (1991) Uncertainty in NCRP Screening Models Relating to Atmospheric Transport, Deposition and Uptake by Humans (1993) Proceedings of the Annual Meeting No Title Perceptions of Risk, Proceedings of the Fifteenth Annual Meeting held on March 14-15, 1979 (including Taylor Lecture No 3) (1980) Critical Issues in Setting Radiation Dose Limits, Proceedings of the Seventeenth Annual Meeting held on April 89, 1981 (including Taylor Lecture No ) (1982) 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 (includingTaylor Lecture No 8) (1985) Radioactive Waste, Proceedings of the Twenty-first Annual Meeting held on April 3-4,1985 (includingTaylor 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 o f the Twenty-third Annual Meeting held on April 8-9,1987 (includingTaylor Lecture No 11)(1988) Radon, Proceedings of the Twenty-fourth Annual Meeting held on March 30-31, 1988 (including Taylor Lecture No 12) (1989) Radiution 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) NCRP PUBLICATIONS 223 Health and Ecological Implications of Radioactively Contaminated Environments, Proceedings of the Twentysixth 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 Twenty-eighth Annual Meeting held on April 1-2,1992 (including Taylor Lecture No.16) (1993) No Lauriston S Taylor Lectures Title The Squares of the Natural Numbers in Radiation Protection by Herbert M Parker (1977) Why be Qwlntitative about Radiation Risk Estimates? by Sir Edward Pochin (1978) Radiation Pmtection-Concepts and Tmde 0fi by Hyrner L Friedell (1979) [Available also in Perceptions of Risk, see above] From "QuantiCy ofRadiationY'and "Dose" to "Exposure" and "Absorbed Dose9'-An Historical Review by Harold 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 abovel Ethics, Trade-offs and Medical Radiation by Eugene L Saenger (1982) [Available also in Radiation Protection and New Medical Diagnostic Approaches, see abovel The Human Environment-Past, Present and Future by Merril Eisenbud (1983) [Available also in Environmental Radioactivity, see abovel Limitation and Assessment i n Radiation Protection by Harald H Rossi (1984) [Available also in Some Issues Important in Developing Basic Radiation Protection Recommendations, see abovel Truth (and Beauty) in Radiation Measurement by John H Harley (1985) [Available also in Radioactive Waste, see abovel Biological Effects of Non-ionizing Radiations: Cellular Properties and Interactions by Herman P Schwan (1987) [Available also in Nonionizing Electromagnetic Radiations and Ultrasound, see abovel 224 NCRP PUBLICATIONS How to be Qwlntitative about Radiation Risk Estimates by Seymour Jablon (1988) [Available also in New Dosimetry at Hiroshima and Nagasaki and its Implications for Risk Estimates, see abovel How Safe is Safe Enough? by Bo Lindell(1988) [Available also in Radon, see abovel 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 Newel1 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 i n Medicine, see abovel Science, Radiation Protection and the NCRP by Warren K Sinclair (1993) Symposium Proceedings The Control of Exposure of the Public to Ionizing Radiation in the EventofAccident orAttack, Proceedings of a Symposium held April 27-29, 1981 (1982) No NCRP Statements 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) Specification of Units ofNatum1 Uraniumand Natural Thorium, Statement of the National Council on Radiation Protection and Measurements, (1973) NCRP PUBLICATIONS / 225 NCRP Statement on Dose Limit for Neutrons (1980) Control of Air Emissions of Radionuclides (1984) The Probability That a Particular M a l i g m c y May Have Been Caused by a Specified Irradiation (1992) 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, February 19, 1960, Vol 131, No 3399, pages 482-486 Dose Effect Modifying Factors I n 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) The following documents are now superseded andlor out of print: No NCRP Reports Title X-Ray Protection (1931) [Superseded by NCRP Report No 31 Radium Pmtection (1934) [Superseded by NCRP Report No 41 X-Ray Protection (1936) [Superseded by NCRP Report No 61 Radium Pmtection (1938) [Supersededby NCRP Report No 131 Safe Handling of Radioactive Luminous Compound (1941) [Out of Print] Medical X-Ray Protection Up to Two Million Volts (1949) [Superseded by NCRP Report No 181 Safe Handling of Radioactive Isotopes (1949) [Superseded by NCRP Report No 301 Recommendations for WasteDisposal of Phosphorus32 and Iodine-131 for Medical Users (1951) [Out of Print] Radiological Monitoring Methods and Instruments (1952) [Superseded by NCRP Report No 571 Maximum Permissible Amounts of Radioisotopes i n the Human Body and Maximum Permissible Concentrations in Air and Water (1953) [Superseded by NCRP Report No 221 Recommendations for the Disposal of Carbon-14 Wastes (1953) [Superseded by NCRP Report No 811 226 / NCRP PUBLICATIONS Protection Against Radiations from Radium, Cobalt-60 and Cesium-137 (1954) [Superseded by NCRP Report No 241 Protection Against Betatron-Synchrotron Radiations Up to 100 Million Electron Volts (1954) [Superseded by NCRP Report No 511 Safe Handling of Cadavers Containing Radioactive Isotopes (1953) [Superseded by NCRP Report No 211 Radioactive- Waste Disposal i n the Ocean (1954) [Out of Print] Permissible Dose from External Sources of Ionizing Radiation (1954) including Maximum Permissible Exposures to Man, Addendum to National Bureau of Standards Handbook 59 (1958) [Superseded by NCRP Report No 391 X-Ray Protection (1955) [Superseded by NCRP Report No 261 Regulation of Radiation Exposure by Legislative Means (1955) [Out of Print] Protection Against Neutron Radiation Up to30 Million Electron Volts (1957) [Superseded by NCRP Report No 381 Safe Handling of Bodies Containing Radioactive Isotopes (1958) [Superseded by NCRP Report No 371 Protection Against Radiations from Sealed Gamma Sources (1960) [Superseded by NCRP Reports No 33,34 and 401 Medical X-Ray Protection Up to Three Million Volts (1961) [Superseded by NCRP Reports No 33,34,35 and 361 A Manual of Radioactivity Procedures (1961) [Superseded by NCRP Report No 581 Exposure to Radiation in a n Emergency (1962) [Superseded by NCRP Report No 421 Shielding for High-Energy Electron Accelerator Installations (1964) [Superseded by NCRP Report No 511 Medical X-Ray and Gamma-Ray Protection for Energies up to 10 MeV-Equipment Design and Use (1968) [Superseded by NCRP Report No 1021 Medical X-Ray and Gamma-Ray Protection for Energies Up to 10 MeV-Structural Shielding Design and Evaluation Handbook (1970) [Superseded by NCRP Report No 491 Basic Radiation Protection Criteria (1971) [Superseded by NCRP Report No 911 Review of the Current State of Radiation Protection Philosophy (1975) [Superseded by NCRP Report No 91.1 Natural Background Radiation in the United States (1975) [Superseded by NCRP Report No 941 Radiation Protection for Medical and Allied Health Personnel (1976) [Superseded by NCRP Report No 1051 NCRP PUBLICATIONS 53 56 58 66 91 No 227 Review ofNCRPRadiation Dose Limit forEmbryo and Fetus in Occupationully-Exposed Women (1977) [Out of Printl Radiation Exposure from ConsumerProducts and MisceUaneous S o u m (1977) [Superseded by NCRP Report No 951 A Handbook of Radioactivity Measurements Procedures, 1st ed (1978) [Superseded by NCRP Report No 58, 2nd Mammography (1980) [Out of Printl Recommendations on Limits fir Exposure to Ionizing Radiation (1987) [Superseded by NCRP Report No 1161 NCRP Proceedings Title Quantitative Risk in Standards Setting, Proceedings of the Sixteenth Annual Meeting held on April 2-3, 1980 [Out of Print] Index Absolute accuracy 87 broadband survey instruments 87 Active antenna 96 Active rod antenna 96 advantages of 96 Amplitude modulation (AM)31 AM radio field-strength values 134 Antenna 8,45,94-100,163,191 active 96 broadband 99 broadband parabolic 99 directional gain (G) 95 circular aperture horn reffector 191 circularly polarized 100 conical log-spiral 100 effective area (A,)95 factor (A,) 94 half-wave dipole 97 log-periodic 98 log-spiral 98 narrowband parabolic reflector 99 omnidirectional 98 passive rod 96 planar log-periodic 98 pyramidal gain horn 99 rotating parabolic reflector 163 rotational duty cycle 115 shielded loop 97 types 94 Antenna characteristics 121 antenna azimuth and elevation 121 gain 121 polarization of the beam 121 m i n i n g rate 121 width of the beam 121 Antenna factor (A,) 94 Antenna fields 126 Antenna rotational duty cycle 116 measurement of 116 Anti-theft devices 174 Area survey 75-76 Automated measurement system 110 block diagram 110 ~ u t o r n a t e measurement d~~ system 112 advantage of 112 Broadband electric-field instruments 83 thermocouple-based 83 Broadband instruments 77,93 peripheral equipment 93 Broadband survey instruments 78,80, 81,84,86,88.89, 90 electromagnetic interference 89 desirable characteristics of 86 diode-based 81,84 dynamic range 88 frequency response 86 isotropic response 86 meter output 89 modem 80 modulation response 92 multiple signal addition 92 out-of-band response 88 peak hold for 90 recorder output 92 response 92 response time 91 spatial resolution 91 stability 91 static-charge sensitivity 90 thermocouple based 84 Circularly polarized antenna 100 Complex permittivity 24 Conductivity 24 Conical log-spiral antenna 100 Data logger 93 broadband instruments 93 Diathermy equipment 151 operational characteristics 151 Decibel 77 definition 77 Derived SI units 13 Desirable characteristics of broadband survey instruments 86-92 absolute accuracy 87 battery operation 91 durability 92 dynamic range 88 ease of adjustment and use 92 230 INDEX electromagnetic interference 89 frequency response 86 isotropic response 86 meter output 89 modulation response 92 multiple signal addition 92 out-of-band response 88 peak hold 90 portability 92 probe burnout alarm 90 probe overload/burnout rating 90 readability 92 recorder output 92 response 89,92 response time 91 spatial resolution 91 stability 91 static-charge sensitivity 90 Dielectric constant Dielectric heating Digital systems 147 measurement of 147 Diode detectors 83 advantages of 83 disadvantages of 83 Diodes 81 point-contact 81 Schottky 81 Dipole moment 23 Directional antenna i26 pyramidal standard gain horn 126 log-periodic 126 Displacement current sensor 85 Displacement flux density 26 Dissipation factor 25 Dosimetry 51 Durability 92 broadband survey instruments 92 Duty cycle (6) 115 Duty factor determination 170 Dynamic range 88 broadband survey instruments 88 Electric-field measurements 60 Electric fields 8,16 Electric-field strength (E) Electric-flux density (displacement) (D) 9,26 Electric polarization Electromagnetic interference 89 broadband survey instruments 89 Electrosurgical and electrocautery units 153 operational characteristics 153 Ellipticity 86 Emission Energy density (surface) Energy density (volume) Evaluation of exposure 68 procedures for 68 Exposure Exposure assessment 124 Exposure evaluation 70 necessary data 70 Exposure limits former Soviet Union Far field 9,34,47,48 Far-field conditions 71 Field point Field-strength meters 78,106,109 usable frequency range 109 response 109 Fourier transform analyzers 101 Frequency Frequency measurement 170 Frequency modulation (FM) 31 Frequency-modulation (FM) radio broadcast 136 operational characteristics 136 Frequency response 86 broadband survey instruments 86 Grating lobe 136 Ease of adjustment and use 92 broadband survey instruments 92 Effective radiated power 46 E polarization 54 Electrical properties of tissue 51 Electric dipole Electric-field instrument 88 desirable dynamic range 88 Electric-field intensity Hand-held portable radios 147,148 operational characteristics 148 Half-wave dipole antenna 97,98 disadvantage of 98 Hazard evaluation procedures 133 Hazards radiofrequency H polarization 54 INDEX Hyperthermia equipment 155 operational characteristics 155 IF amplifier 104 Impedance, wave Isotropic response 86 broadband survey instruments 86 K polarization 54 Leakage fields 121,122 LORANIOMEGA navigational stations 184 operational characteristics 184 Lorentz force 17 Loss tangent 25 Lossy 9,63 Magnetic field 9,17 Magnetic-field instrument 80,88 design of 80 desirable dynamic range 88 Magnetic-field measurements 61 Magnetic-field probes 87 frequency range of 87 frequency response of 87 Magnetic-field strength (H) 10,27 Magnetic-flux density (B)10.17 Magnetic resonance imaging systems 157 operational characteristics 157 Marine radar 163 operational characteristics 163 Measurement of 61,62 magnetic fields 61 specific absorption rate (SARI 62 Measurement accuracy 127 precautions for ensuring 127 Measurement of operator exposure 170 Measurement techniques 77, 135, 138,142, 144,146,148,150, 152, 154,156,158,162, 164,166,167, 175,177,178,179,181,185 AM radio 135 anti-theR devices 175 diathermy equipment 152 electrosurgical and electrocautery units 154 / 231 FM radio 138 hand-held portable radios 148 hyperthermia equipment 156 LORANIOMEGA navigational stations 185 magnetic resonance imaging systems 158 marine radar 164 microwave door openers 177 microwave industrial heating1 drying equipment 167 microwave intrusion alarms 178 microwave ovens 179 microwave radio 144 mobile radios 150 police radar 166 radar 162 satellite communication 146 sports radar 166 television 142 visual-display terminals 181 Meter output 89 broadband survey instruments 89 Microwave door openers 176 operational characteristics 176 Microwave industrial heatingtdrying equipment 166 operational characteristics 166 Microwave intrusion alarms 177 operational characteristics 177 Microwave ovens 178 operational characteristics 178 Microwave radio 142 operational characteristics 142 Mobile radios 149-150 operational characteristics 150 Modulation 29 Modulation response 92 broadband survey instruments 92 Multiple signal addition 92 broadband survey instruments 92 Mutual coupling 85 Narrowband instruments 78 field-strength meters 78 spectrum analyzers 78 Narrowband survey instruments 110 limitations of 110 Narrowband systems 93 Near field 10,34,47,48 Near-field conditions 71 Nodes 35 232 / INDEX Nonmagnetic materials 22 Nonplanar objects 39 Out-of-band response 88 Oven survey instrument 86 response of 86 Passive rod antenna 96 Peak hold 90 broadband survey instruments 90 Permeability 10 Permittivity (010,24,51 frequency dependence 51 Permittivity of free space 16 Phase shifl keying (PSK) 143 Phase velocity 10,27 Planar dielectrics 37 Planar log-periodic antenna 98 Planar models 52 Planar wave 10,33 Polarization 53 Polarization charge 23 Polarization of EM wave 10 Police radar 165 operational characteristics 165 Portability 92 broadband survey instruments 92 Power density 10 Power meter 118 Poynting's Theorem 40 Poynting vector (S) 10,40 Probe burnout alarm 90 broadband survey instruments 90 Probe overload/burnout rating 90 broadband survey instruments 90 Propagation coefficient 10 Protection guide 68-69 criteria 68 single-value 69 frequency dependent 69 Protection of the operator 128 precautions for 128 Pulse-repetition frequency Vp) 115 Pyramidal gain horn antenna 99 Quadrature amplitude modulation (&AM)143 Quasi-narrowband instruments 77, 119 advantage of 119 Quasi-narrowband system 78, 117 frequency range 78 Quasi-static fields 22 Radar 158 operational characteristics 158 Radar exposure measurements 162 Radian frequency 11 Radiation patterns 49 Radiofrequency 1-3, 6.59 band designations hazards protection guides 59 safety standards spectrum Radiofrequency dielectric heaters 171 operational characteristics 171 Radiofrequency induction heaters 168 operational characteristics 168 Readability 92 broadband survey instruments 92 Recorder output 92 broadband survey instruments 92 Reflection coefficient 11 Relative permittivity 11 Response to environmental factors 92 broadband survey instruments 92 Response to the parameter being measured 89 broadband survey instruments 89 Response time 91 broadband survey instruments 91 Safety standards Satellite communicationearth stations 144 operational characteristics 144 Scalar 12 Scattered fields 34,43 Secondary sources 74 effects of 74 Shielded loop antenna 97 Short dipole 79 effective length of 79 Sidelobes 136 Spatial averaging 72 Spatial resolution 91 broadband survey instruments 91 Special measurements 129 Specific absorption rate (SAR) 11 INDEX Specific absorption rate characteristics 55 Specific absorption rate measurements 62 Spectrum analyzers 78,101, 103, 105, 108,115 amplitude response 108 measurement e m r 105 real-time 101 superheterodyne 103 swept-tuned 101, 103 Spherical waves 11,31 Sports radar 165 operational characteristics 165 Square-law response 84 Stability 91 broadband survey instruments 91 Standing-wave ratio 11,38 Static-charge sensitivity 90 broadband survey instruments 90 Static-electric fields 18 Static-magnetic fields 20 Survey procedures 170 Swept-tuned spectrum analyzer 103 Television broadcast 139 operational characteristics 139 233 Temperature compensated power meter 118 Thermocouple-based instruments 84 advantage of 84 disadvantage of 84 Thermocouples 83 Thermocouple-type magnetic fieldprobe 87 frequency response of 87 Thermocouple-type sensor 118 Time averaging 72 Traveling wave 28 Vector 11.12 Vector cross product 14,15 Vector dot product 14, 15 Velocity of propagation 11 Visual-display terminals (VDT)85, 180 measuring fields associated with 85 operational characteristics 180 Wave impedance 11 Wavelength 11 Wave propagation 27 Whole-body average SAR 55 ... Cataloging-in-PublicationData National Council on Radiation Protection and Measurements A practical guide to the determination of human exposure to radiofrequency fields : recommendations of the. .. contains a brief explanation of vectors and vector notation A scalar is a quantity that has magnitude only In contrast to this, a vector is a quantity that has magnitude and direction A familiar example... plane wave in a material, the wave impedance is equal to 377 times the square root of the ratio of the relative permeability to the relative permittivity of the material lossy: A material characteristic