Table Of ContentNCRP REPORT No. 72
RADIATION PROTECTION
AND MEASUREMENT
FOR LOW-VOLTAGE
NEUTRON GENERATORS
Recommendations of the
NATIONAL COLlNClL ON RADIATION
PROTECTION AND MEASUREMENTS
Issued November 1,1983
First Reprinting October 15, 1990
National Council on Radiation Protection and Measurements
7910 WOODMONT AVENUE / BETHLSDA, MD. 20814
LEGAL NOTICE
This report waa prepared by the National Council on Radiation Protection and Meas-
urements (NCRP). The Council strives to provide accurate, complete and useful infor-
mation in its reports. However, neither the NCRP. the members of NCRP, other persons
contributing to or aesisting in the preparation of thie report, nor any pereon acting on
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method or pracese dkloaed in this report.
Library of ~0ngTe11(C1 ataloging in Publication Data
National Council on Radiation Protection and Measwmenta
Radiation protection and measurement for low-voltage neutron generators.
(NCRP repcrt ;n o. 72)
"leeued November 1,1983."
Bibliography: p. 69
Includes index.
1. Neutron eources-Safety measures. 2. Radiation-Measurement. 3. Radiation do-
simetry. I. Title. 11. Series.
QC793.6.N4622N37 1983 537.7'213'0!289 83-62802
ISBN 0-913392-61-8
Copyright Q National Council on Radiation
Protection and Measurements 1983
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Contents
Preface ..................................................i ii
.
1 Introduction ........................................... 1
.
2 Radiations Produced by Low-Voltage Neutron
Generatore ............................................ 2
2.1 Neutrons ........................................... 2
2.2 XRays ............................................. 5
2.3 Gamma Rays ....................................... 6
. 2.4 Induced Radioactivity ............................... 6
3 Fundamentale of Radiation Protection ................ 8
3.1 Control of Exposure to Radiation ..................... 8
3.2 Permissible Limits ................................... 8
3.3 RadiationSurveys .................................... 12
3.4 Personnel Monitoring ................................ 13
3.5 Radiation Protection Personnel ....................... 14
. 3.6 "Overexposure" ..................................... 15
4 Shielding and Other Physical Safeguards ............... 16
4.1 Shielding ...........................................16
4.2 Other Physical Safegum& ......................... - 22
.
6 Measurement of Radiation ............................ 24
5.1 Dose Equivalent .................................... 24
5.2 Measurement of External Radiation ................... 27
5.3 Measurement of Tritium .............................3 0
.
6 Radioactive Waste: Nature, Sourcee, Handling, and
Storage ............................ ................ 33
.-
6.1 Nature of Radioactive Waste ......................... 33
6.2 Sources of Radioactive Waste ........................ 34
6.3 Handling and Stoxage of Contaminated Waste .......... 37
7 . Other Hazards ..................... .. ................ 40
7.1 Electrical Hazards ................................... 40
7.2 Implosion of Evacuated Glass Components ............. 40
7.3 NoxiousGases ...................................... 40
. 7.4 Fire Protection ...................................... 40
8 Licensing ............................... .. ......... 41
APPENDIX A Definition8 ................................. 42
APPENDIX B Measurement of Tritium .................. 45
APPENDIX C D-T Neutron Shielding .................... 49
APPENDIX D NCRP Statement on Doee Limit for
Neutrons ................................................. 56
References ................................................ 69
. The NCRP ................................................ 65
NCRP Publications ........................................ 72
Index ..................................................... 81
