1、 American National Standard ANSI/HPS N43.9-2015 For Gamma Radiography Specifications for the Design, Testing, and Performance Requirements for Industrial Gamma Radiography System Equipment Using Radiation Emitted by a Sealed Radioactive Source Approved 17 April 2015 American National Standards Insti
2、tute, Inc. Published by Health Physics Society 1313 Dolley Madison Blvd. Suite 402 McLean, VA 22101 Copyright 2015 by the 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 perm
3、ission of the publisher. Printed in the United States of America ANSI/HPS N43.9-2015 The N43-3.5 subcommittee members were: R. D. “Donny” Dicharry, Chair Source Production initially ISO-3999-1-2000 and then ISO-3999-2004 later in the process. The subcommittee sought to harmonize with ISO-3999 as muc
4、h as practical. This edition cancels and replaces ANSI N43.9-1991. There was parity among stakeholders in the revision process with manufacturers, users and government regulators involved and consensus agreement among the subcommittee members for approval of the revision was achieved. After the draf
5、t revision was submitted to N43 for approval numerous comments, primarily editorial, were returned to the subcommittee. The comments were addressed without the need for substantive revisions. The draft was resubmitted to N43 for approval and additional comments, including a negative vote, were retur
6、ned. All comments were addressed and the negative vote was reversed. AMERICAN NATIONAL STANDARD ANSI/HPS N43.9-2015 1 For Gamma RadiographySpecifications for the Design, Testing, and Performance Requirements for Industrial Gamma Radiography System Equipment Using Radiation Emitted by a Sealed Radioa
7、ctive Source 1.0 Scope This standard specifies the design, testing, and performance requirements for industrial gamma radiography system equipment and source changers using radiation emitted by a sealed radioactive source. The standard includes the qualification requirements for those who engage in
8、the design, fabrication, assembly, testing, repair, or modification of industrial gamma radiography system equipment or source changers. The operational use of such equipment is not covered by this standard.1 Those provisions containing the word “shall” identify requirements that are necessary to me
9、et the standards of protection in this document. Those using the word “should” indicate advisory recommendations that are to be applied when practical. 2.0 Normative References The following standards contain provisions that are referenced in this standard. At the time of publication the editions in
10、dicated were valid, yet all standards are subject to revision. Users of this standard should evaluate the applicability of revisions to those standards. Health Physics Society. American national standard: Radiation symbol. McLean, VA; ANSI N2.1-2011; 2011. Health Physics Society. American national s
11、tandard: Sealed radioactive 1 If exposure devices are to be used as radioactive material transport packages, they shall also comply with current applicable transport regulations. sourcesclassification. McLean, VA; ANSI/HPS N43.6-2007 (R2013); 2013. 3.0 Definitions and Abbreviations The definitions,
12、terms, and abbreviations contained in this standard, or in other Amer-ican national standards referred to in this document, are not intended to embrace all legitimate meanings of the terms. They are applicable only to the subject treated in this standard. Commonly used industry terms are in brackets
13、. 3.1 Definitions Associated equipment: Equipment that is used in conjunction with an exposure device that drives, guides, or comes into contact with the source assembly. This includes, but is not necessarily limited to, control assem-blies, source guide tubes, and collimators when used as source st
14、ops. Automatic securing mechanism (ASM): A feature of an exposure device that automati-cally secures the source assembly when it is cranked back into the fully shielded position within the device. The ASM may only be released by means of a deliberate operation on the exposure device or control assem
15、bly. Capacity: The maximum output activity in becquerels (curies) specified for a given ra-dionuclide that may be contained in an ex-posure device or source changer. Category: Type of exposure device based upon its intended use and the location of the sealed source when it is in the exposed po-sitio
16、n. Class: Type of exposure device based upon its mobility. Collimator (beam limiter): A shielding component used to limit the size, shape, or direction of the primary radiation beam. Control adaptor: A component of the con-trol assembly that attaches the control as-sembly to the exposure device. Con
17、trol assembly (remote control): An assembly that enables the sealed source(s) to be moved to the exposed position by ANSI/HPS N43.9-2015 2 operation at a distance away from the expo-sure device. For crank-out devices the con-trol assembly includes the control drive mechanism, control assembly condui
18、t, drive cable, and control adaptor, as applicable. Control assembly conduit (drive cable housing, control tube, control-cable sheath): A component of the control as-sembly that connects the control drive mechanism to the control adaptor whose purpose is to guide the drive cable from the control dri
19、ve mechanism to the exposure device. Control drive mechanism (crank): A com-ponent of the control assembly that mechan-ically engages and moves the drive cable. Critical components of associated equipment: Those components that are essential for the safe operation of the expo-sure device to prevent
20、a misconnect or dis-connect. For a crank-out device these in-clude the source guide tube connector, con-trol adaptor, drive cable, drive cable con-nector, and source assembly. Disconnect: A condition in which the source assembly is inadvertently released from the drive cable. Drive cable: An assembl
21、y consisting of a cable and a drive cable connector used to move the source assembly in and out of the fully shielded position. Drive cable connector: A component used to attach the drive cable to the source as-sembly. Exposed position: Condition of the expo-sure device and source assembly in which
22、the sealed source is unshielded for the per-formance of radiography. Exposure device (camera, projector): A shielded device employing one or more sealed sources designed to allow the con-trolled use of gamma radiation for the pur-pose of making a radiographic exposure. Exposure device source path: A
23、 hollow tunnel inside the shield (commonly called an S-tube) in Category II (crank-out) exposure devices. Fully shielded position: The position within the exposure device or source changer where the sealed source is designed to re-turn after use, to remain when not in use, and in which the sealed so
24、urce is designed to be acceptably shielded.2 Gamma constant: The exposure rate of the sealed source per unit activity (also called the specific exposure rate constant). Industrial gamma radiography system: All integral components necessary to perform industrial radiography, including the expo-sure d
25、evice, source assembly, and as appli-cable, associated equipment. See Figure 1. Industrial radiography: An examination of the structure of materials by nondestructive methods utilizing ionizing radiation to make radiographic images. Locked position: Condition of the exposure device or source changer
26、 and source as-sembly in which the sealed source is in the fully shielded position and restricted from movement from the exposure device or source changer and the exposure device or source changer lock is engaged. Misconnect: A condition in which the con-trol assembly can be attached to the expo-sur
27、e device without attaching the drive cable to the source assembly. Output activity: The exposure rate of the sealed source divided by the gamma con-stant (Table 1). Production model: A product with specifi-cations that are identical to the prototype(s) tested and confirmed to meet the standard. Prot
28、otype: A product designed and fabri-cated for testing that conforms in all vital characteristics to production models fabri-cated subsequently. 2 In the fully shielded position, the exposure device or source changer may be unlocked. ANSI/HPS N43.9-2015 3 Figure 1. Industrial gamma radiography system
29、. Table 1. Output activity. Radionuclide Gamma constant Iridium-192 0.48 R h-1 Ci-1 1 m 130 Sv h-1 GBq-1 1 m Cesium-137 0.32 R h-1 Ci-1 1 m 86 Sv h-1 GBq-1 1 m Cobalt-60 1.30 R h-1 Ci-1 1 m 351 Sv h-1 GBq-1 1 m Selenium-75 0.20 R h-1 Ci-1 1 m 54 Sv h-1 GBq-1 1 m Ytterbium-175 0.125 R h-1 Ci-1 1 m 34
30、 Sv h-1 GBq-1 1 m ANSI/HPS N43.9-2015 4 Sealed source (capsule, pill): A radioactive source sealed in a capsule or having a bonded cover, the capsule or cover being strong enough to prevent contact with and dispersion of the radioactive material under the conditions of use and wear for which it was
31、designed. Secured position: Condition of the exposure device and source assembly when the sealed source is captured automatically in the fully shielded position and is restricted from movement. In the secured position, the exposure device need not be locked. Source assembly (pigtail): An assembly th
32、at consists of a sealed source and the component(s) necessary for use. For Category II source assemblies, this typically consists of a connector, sealed source, cable, and locking ball. Source changer: A device used to store, transport, and exchange source assemblies for use in exposure devices. Sou
33、rce guide tube (source tube, guide tube, projection sheath): A flexible or rigid tube for guiding the source assembly to and from the exposure device. Source guide tube connector: A component used to attach the source guide tube to the exposure device. Source holder: Holder or attachment component b
34、y means of which a sealed source can be secured in the exposure device or attached to the end of the source assembly. Note: Source holders may be an integral part of the source assembly or may be capable of being dismantled for sealed source replacement. Source stop (exposure head, end piece, end st
35、op): A component of the guide tube that stops the sealed source in the exposed position. 3.2 Abbreviations C Celsius CFR Code of Federal Regulations cm centimeter Ci curie F Fahrenheit ft foot GBq gigabecquerel Gy gray h hour in inch ISO International Standards Organization kg kilogram lb pound m me
36、ter or milli (10-3) mm millimeter mrem millirem mSv millisievert N newton QA quality assurance R roentgen s second SI Systme International dUnites (International System) Sv sievert micro (10-6) Sv microsievert 4.0 Device Class and Category For the purpose of this standard, an exposure device is clas
37、sified according to its portability, location of the sealed source when it is in the exposed position, and use. 4.1 Class of Exposure Device Class P (portable): A portable exposure device designed to be carried by one or more persons. The device mass shall not exceed 50 kg (110 lb). Class M (mobile)
38、: A mobile, but not portable, exposure device designed to be moved easily by a suitable means provided for that purpose. Class F (fixed): An exposure device that is designed to be installed in a fixed location. 4.2 Category of Exposure Device Category I: An exposure device from which the sealed sour
39、ce is not removed for exposure. The beam of radiation is exposed by opening a shutter, by moving the sealed source within the device, or by other means. Category II: An exposure device from which the sealed source is remotely projected out of the exposure device. ANSI/HPS N43.9-2015 5 Category X: Eq
40、uipment for industrial gamma radiography designed for special applications where the unique nature of the special application precludes full compliance with ANSI/HPS N43.9; for example, self-propelled industrial gamma radiography system equipment (pipe-line crawlers). The industrial gamma radiograph
41、y system equipment shall comply with this standard to the maximum extent possible. Exceptions and items of noncompliance shall be clearly described in the manufacturers accompanying documents. 5.0 Design and Performance 5.1 General Design Requirements Industrial gamma radiography system equipment sh
42、all be designed for the conditions likely to be encountered in use when the equipment is used and maintained in accordance with the manufacturers instructions. The design of the industrial gamma radiography system equipment shall ensure satisfactory operation in the expected temperature range of use
43、. This range is -10 C to 45 C (14 F to 113 F). The design of the equipment shall minimize the effect of the environmental conditions of moisture, sand, mud, and other foreign matter that the equipment is likely to encounter during use. The equipment shall be designed to withstand the possible damagi
44、ng effects of gamma radiation on nonmetallic materials of construction such as rubber, plastic, jointing and sealing compounds, and lubricants in close proximity to the source. The equipment shall pass the tests prescribed by this standard. The exposure device shall be designed to allow connecting a
45、nd disconnecting associated equipment without requiring parts of the human body to come into the unattenuated beam of radiation in close proximity to the source. The design of any replacement component shall ensure that its interchange with the original component will not reduce the safety of the in
46、dustrial gamma radiography system equipment. The exposure device shall have a lock that requires special tools to be dismantled or removed. When depleted uranium is used as the shielding material of an exposure device, it shall be clad or encased with a nonradioactive material of sufficient thicknes
47、s to absorb the beta radiation. If the nonradioactive cladding or encasement is liable to react with the depleted uranium at elevated temperatures, then the depleted uranium shall be given suitable surface treatment to inhibit this effect. An exposure device with depleted uranium shielding and a sou
48、rce path (S-tube) shall be clad with a nonradioactive material to prevent corrosion and wear to the depleted uranium shield. All openings of the exposure device, control assembly, and source guide tube shall be equipped with safety plugs or other means to minimize the entry of foreign matter. Source
49、 changers shall be designed to ensure that the sealed source will not be accidentally withdrawn from the source changer when connecting or disconnecting the drive cable to or from the source assembly. 5.2 Shielding Efficiency An exposure device shall be made in such a way that when in the locked position, with safety plugs in place (if applicable), and equipped with sealed source(s) corresponding to the capacity of the exposure device, the dose rate, when tested as described in Section 6.2.1, does not exceed the limits in Table 2. 5.3 Safety Devices
