ANSI HPS N43.1-2011 Radiation Safety for the Design and Operation of Particle Accelerators.pdf

1、 American National Standard ANSI/HPS N43.1-2011 Radiation Safety for the Design and Operation of Particle Accelerators Approved: November 9, 2011 American National Standards Institute, Inc. Published by Health Physics Society 1313 Dolley Madison Blvd. Suite 402 McLean, VA 22101 Copyright 2011 by the

2、 Health Physics Society. All rights reserved. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior written permission of the publisher. Printed in the United States of America ANSI/HPS N43.1-2011 iii The Accredited Standards Committ

3、ee N43, on Equipment for Non-Medical Radiation Applications, had the following membership at the time it processed and approved this standard (27 September 2011): Chairperson William Morris Vice-chairperson Scott O. Schwahn ABB Industrial Systems, Inc. John R. Dukes American Conference of Government

4、 Industrial Hygienists Gordon Lodde American Iron and Steel Institute Anthony LaMastra American Society for Testing and Materials Marvin M. Turkanis Canadian Nuclear Safety Commission Slobodan Jovanovic Health Physics Society Sander Perle Los Alamos National Laboratory Scott Walker National Council

5、on Radiation Protection and Measurement Susan M. Langhorst National Institute of Standards and Technology James S. Clark Underwriters Laboratories, Inc. Peter Boden U.S. Department of the Air Force, Office of the Surgeon General Ramchandra Bhat U.S. Department of the Army, Office of the Surgeon Gene

6、ral Frances Szrom U.S. Department of the Army Gregory R. Komp U.S. Department of Energy Peter OConnell U.S. Department Health, Education, and Welfare, Public Health Service Daniel F. Kassiday U.S. Department of Homeland Security Siraj M. Khan U.S. Department of the Navy Brendon K. Glennon U.S. Nucle

7、ar Regulatory Commission John P. Jankovich Individual members: Susan J. Engelhardt David W. Lee iv The ANSI/HPS N43.1 Standards Subcommittee responsible for writing had the following members: James C. Liu, Co-chair (SLAC National Accelerator Laboratory, Menlo Park, CA) Lawrence S. Walker, Co-chair (

8、Los Alamos National Laboratory, Los Alamos, NM) Ted de Castro (Lawrence Berkeley National Laboratory, Berkeley, CA, retired) John Drozdoff (TRIUMF, Vancouver, BC, Canada) Wesley M. Dunn (Texas State Department of Health and Safety, retired) Olin Van Dyck (Los Alamos National Laboratory, Los Alamos,

9、NM, retired) Albert E. Evans (U.S. Department of Energy, DC, retired) Roger Kloepping (Lawrence Berkeley National Laboratory, Berkeley, CA, retired) Larry Larson (Sematech, Inc., Austin, TX, retired) Robert May (Thomas Jefferson National Accelerator Facility, Newport News, VA) Norman Rohrig (Idaho N

10、ational Engineering and Environmental Laboratory, Idaho Falls, ID, retired) Paula Trinoskey (Lawrence Livermore National Laboratory, Livermore, CA, retired) Vashek Vylet (Thomas Jefferson National Accelerator Facility, Newport News, VA) v Contents 1.0 Purpose, Scope, and Introduction . 1 1.1 Purpose

11、 . 1 1.2 Scope 1 1.3 Introduction 1 2.0 Acronyms, Abbreviations, and Definitions . 3 2.1 Common Acronyms and Abbreviations . 3 2.2 Definitions 3 3.0 Radiation Safety Program . 8 3.1 General 8 3.2 Organization and Administration 9 3.2.1 Facility Management and Operation . 9 3.2.2 Radiation Safety Pro

12、fessionals . 9 3.2.3 Radiation Safety Officer and Radiation Safety Committee . 9 3.3 Hazard Identification and Safety Assessment 9 3.4 Design and Implementation of Safety Controls and Monitoring . 10 3.4.1 Radiation Safety System (RSS) 10 3.4.2 Safety Envelope and Operation Envelope 11 3.5 Accelerat

13、or Operations 11 3.6 Operational Radiation Safety . 12 3.7 Training and Qualification 12 3.8 Program Review and Performance Evaluation 12 3.9 Quality Assurance, Quality Control, and Configuration Control . 13 3.10 Document and Record Management . 13 4.0 Radiation Safety System (RSS) 14 4.1 General 1

14、4 4.2 Features of the Radiation Safety System (RSS) 14 4.3 Requirements and Guidance . 15 4.3.1 Reliability and Fail-Safe 15 4.3.2 Tamper Resistance 16 4.3.3 Quality Assurance 16 4.3.4 Configuration Control 16 4.4 Radiation Not Related To Accelerator Beam . 16 4.5 Induced Radioactivity 16 5.0 Access

15、 Control System (ACS) 17 5.1 Purposes . 17 5.2 Graded Approach 17 5.3 System Features . 18 5.3.1 Warnings and Signs . 18 5.3.2 Enclosures 19 5.3.3 Personnel Entryway Doors/Gates . 19 5.3.4 Exclusion Area 20 5.4 Beam Inhibiting Devices (BIDs) . 20 5.5 Interlocks . 20 5.5.1 Functional Requirements 20

16、5.5.2 Redundancy . 21 5.5.3 Design Considerations . 21 5.5.4 Use of Computer-Based Logic Systems . 21 5.6 Review . 22 5.7 Certification and Checks 22 vi 6.0 Radiation Control System (RCS) 23 6.1 General 23 6.2 Performance Requirements . 23 6.2.1 Normal Operation . 23 6.2.2 Abnormal Operation . 24 6.

17、3 Passive Systems: Shielding and Fences . 25 6.4 Active Systems 25 6.4.1 Beam Interlocks 26 6.4.2 Radiation Interlocks 26 6.5 Administrative Controls 26 7.0 Accelerator Operations . 26 7.1 General 26 7.2 Readiness Review . 27 7.3 Operating Practices . 27 7.4 Testing, Routine Maintenance and Unschedu

18、led Repairs . 28 7.5 Interlock Bypasses and Deviations from Procedures 28 7.6 Emergency Response . 29 8.0 Operational Radiation Safety 29 8.1 General 29 8.2 Area Classification, Worker Classification and Access Control . 30 8.3 Personnel Dosimetry . 30 8.4 Area Monitoring . 32 8.5 Radiation Surveys

19、. 32 8.6 Radiological Work Control . 33 8.7 Control of Induced Radioactivity 34 8.8 Instrumentation 35 8.9 Management of Radioactive Material, Sources and Waste . 35 8.10 Radiological Environmental Protection 36 8.11 Facility Cleanup and Decommissioning . 37 9.0 Training 38 9.1 General 38 9.2 Proced

20、ures and Records . 38 9.3 Training Requirements 38 9.3.1 Exemption. 39 9.3.2 Reciprocity 39 9.3.3 Retraining . 39 9.4 Radiation Safety Training Program 39 9.5 Training Topics 39 9.5.1 Radiological Hazards 39 9.5.2 Other Hazards 40 9.5.3 Operational Controls . 40 9.6 Trainer Qualifications . 40 Appen

21、dix A: Development of Safety Assessment Document (SAD) 41 Appendix B: Interlocked-Type Access Control Systems.44 Appendix C: Decommissioning Program.47 Appendix D: Measurements of Radiation and Radioactivity49 Appendix E: Safety Standards for Commercially Available and/or Production-Type Accelerator

22、s.58 References.63Resources64vii Preface The previous ANSI N43.1 standard was published for use in December 1969 and covered mainly technical aspects with a stipulation that the standard applied principally to accelerators with energies less than 100 MeV. In 1974, a review of the standard was conduc

23、ted that resulted in changes (principally dosimetric quantities) and a revised standard that was approved in July 1978. Currently, accelerators exist in a variety of types, sizes, power capabilities, operational modes, and applications. Therefore, accelerators can vary widely in their radiation haza

24、rd producing capacity and diversity, and the hazard analysis and control are more complex and challenging. The regulatory environment is also more demanding. This new N43.1 standard is developed to address the hazards and controls for accelerators in the current technical, operational, and regulator

25、y environment. The goal is to provide a consistent and sound radiation protection framework for accelerator community. The new N43.1 standard has the following major new elements and/or changes: 1. It covers most fixed, non-medical accelerators, encompassing most particle types and energies. 2. It c

26、overs all phases of the accelerator facility (the life-cycle approach). 3. It addresses both technical and management aspects of the radiation safety program. 4. It sets requirements and recommends good practices for the protection of workers, the public, and the environment. 5. It takes a graded ap

27、proach for the hazard control that is commensurate with the risk levels. 6. It addresses the subjects of engineered and/or interlocked safety systems for prompt radiation and accelerator operations in more detail. AMERICAN NATIONAL STANDARD ANSI/HPS N43.1-2011 1 Radiation Safety for the Design and O

28、peration of Particle Accelerators 1.0 Purpose, Scope, and Introduction 1.1 Purpose This standard sets forth accelerator facility ionizing radiation safety requirements for workers, public, and the environment pro-duced during and from accelerator opera-tions. This standard also recommends good pract

29、ices that provide a level of radiation protection consistent with those established across the accelerator community. 1.2 Scope This standard applies to all phases of the accelerator facilitys life cycle, including design, installation, commissioning, opera-tion, maintenance, upgrade, and decom-miss

30、ioning. This standard specifies requirements and recommendations for radiation safety program management and technical aspects. This standard is suitable for all accelerator facilities using electron, positron, proton, or ion particles capable of producing ionizing radiation hazards. However, accele

31、rators used within a formalized medical setting directly for diagnosis and/or therapy, such as medical accelerators used for radio-therapy and radio-diagnosis in hospitals, are not covered by this standard. Accelerator facilities covered by this standard include, but are not limited to, the followin

32、g accelerator systems: Small table-top accelerators Radiography machines 1 MeV (inspection systems for security, contraband, etc.) Industrial accelerators (ion implanters, electron beam welders, medical sterili-zation accelerators, etc.) Accelerators such as cyclotrons produ-cing radioisotopes for m

33、edical or non-medical uses Facilities manufacturing and testing medical or industrial accelerators Multi-use facilities that use accelerators for both medical and non-medical purposes (sub-facilities used only for medical purposes are excluded) Van de Graaff and other DC-type accelerators Pulse beam

34、 machines providing high peak currents at low duty factors Large, high-dose-rate R the traditional unit is the rem (1 Sv = 100 rem). See ICRP-60 (1991) and ICRP-103 (2007) for details. In this standard, the terms effective dose, equivalent dose, and dose may be used interchangeably for personnel pro

35、tection. This standard also acknowledges that, though the latest ICRP-recommended personnel dosimetric quantities have not been universally adopted and used in the United States, the numerical dose values quoted in this standard can be applied without correction for the small differences between dif

36、ferent types of quantities. Equivalent Dose: The product of the dose, in SI unit of gray (Gy) or traditional unit of rad (1 Gy = 100 rad), in an organ or tissue and the radiation weighting factor (wR, unitless) for the radiation incident on the human body. The SI unit of equivalent dose is the sieve

37、rt (Sv); the traditional unit is the rem (1 Sv = 100 rem). See ICRP-60 for details. Exclusion Area: An area in which access by personnel is prohibited and/or restricted ANSI/HPS N43.1-2011 5 by physical barriers with at least a locked entryway door/gate (interlock is also recommended). Areas with a

38、prompt radiation dose level 10 mSv h1 (1 rem h1) are classified as exclusion areas. An area secure system is required to ensure no one is left inside the exclusion area prior to accelerator operation. Expert (Qualified Expert): An individual who has the appropriate combination of education and work

39、experience to make sound judgments regarding specific work areas to which he/she has been assigned. Minimum qualifications should include a bachelors degree in a science/engineering field and three years of relevant work experience at accelerator or industrial facilities. A higher degree of educatio

40、n can substitute for some working experience. For example, a worker authorized to design and/or certify an interlocked access control system shall have education, experience and training that is commensurate with the tasks assigned. A radiation safety profes-sional is a qualified expert in the areas

41、 of radiation safety. Fail-safe: A feature of an interlocked safety system that renders the accelerator system safe when a component of the safety system fails. Failure Resistant: A safety system in which some components have been backed-up, reinforced or selected to lessen the probability of failur

42、e but not to the extent required for a fail-safe designation. Gate: A device allowing controlled access to areas that are not normally occupied. Graded Approach: An approach that provides enhanced radiation safety by incrementally augmented restrictive safety measures as radiation risks increase. Ha

43、zard: A source of danger (material, energy source, or operation) with potential to cause illness, injury, death, or damage to the facility and/or environment (without considering the likelihood or credibility of accident scenarios or consequence mitiga-tion). High Radiation Area: An area accessible

44、to individuals in which radiation levels from radiation sources external to the body could result in an individuals receiving an effective dose in excess of 1 mSv (0.1 rem) in 1 h at 30 cm from a radiation source or from any surface that radiation penetrates. Induced Radioactivity: Radioactivity pro

45、-duced in materials exposed to an accelerator beam and/or its secondary particles. Interlock: A device or device group arranged to sense a limit, an off-limit condition, or improper event sequence that function(s) to shut down the equipment or prevent its operation. Interlocks are specifically desig

46、ned to prevent and/or terminate a hazardous condition. Interlock System: An engineered control system that includes interlock devices and interlock logic. It continuously receives feedback information from sensors, makes decisions about the safety of the area and activates mitigation or beam inhibit

47、ing devices. In general, the interlock system in this standard refers to personnel protection, though there are also interlock systems for machine (or equipment) protection (machine protection system). Logic System: A system that relates sensors, feedbacks, and active elements that functions in rela

48、tion to a given set of input conditions to trigger a given set of actions. The system is usually documented by including an architectural flow diagram. Maximum Credible Beam Power (MCBP): The maximum power that can be imparted to accelerated beam particles without making significant beam source or a

49、ccelerating structure changes. The MCBP is used to evaluate the RCS requirements under abnormal operation. The MCBP is greater than or equal to the ABP. Normal Beam Losses: Beam losses that are anticipated as part of routine and planned operation, such as a 100% beam loss in a beam stop (or shutter) or a fraction of beam loss in a collimator. This is treated