BS ISO 7503-1-2016 en_4496 Measurement of radioactivity Measurement and evaluation of surface contamination General principles《放射性的测量 表面污染的测量和评价 通用原则》.pdf

1、BSI Standards Publication BS ISO 7503-1:2016 Measurement of radioactivity Measurement and evaluation of surface contamination Part 1: General principlesBS ISO 7503-1:2016 BRITISH STANDARD National foreword This British Standard is the UK implementation of ISO 7503-1:2016. The UK participation in its

2、 preparation was entrusted to Technical Committee NCE/2, Radiation protection and measurement. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are respons

3、ible for its correct application. The British Standards Institution 2016. Published by BSI Standards Limited 2016 ISBN 978 0 580 81285 9 ICS 13.280 Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standar

4、ds Policy and Strategy Committee on 29 February 2016. Amendments/corrigenda issued since publication Date T e x t a f f e c t e dBS ISO 7503-1:2016 ISO 2016 Measurement of radioactivity Measurement and evaluation of surface contamination Part 1: General principles Mesurage de la radioactivit Mesurag

5、e et valuation de la contamination de surface Partie 1: Principes gnraux INTERNATIONAL STANDARD ISO 7503-1 Second edition 2016-01-15 Reference number ISO 7503-1:2016(E)BS ISO 7503-1:2016ISO 7503-1:2016(E)ii ISO 2016 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2016, Published in Switzerland

6、All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested

7、 from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgBS ISO 7503-1:2016ISO 7503-1:2016(E)Foreword iv Intro

8、duction v 1 Scope . 1 2 Normative references 1 3 T erms and definitions, s ymbols and abbr e viations . 2 3.1 Terms and definitions . 2 3.2 Symbols and abbreviated terms. 3 4 Objecti v es of surfac e c ontamination measur ements . 4 4.1 General . 4 4.2 National and international regulations 4 4.3 De

9、finition of the measuring programme 4 5 Direct and indirect methods of assessing surface contamination 5 5.1 General . 5 5.2 Direct method 6 5.3 Indirect method (wipe tests) 6 5.4 Wipe test uncertainties 6 6 Radionuclide identification and spectr al anal y sis 6 7 Monitoring instruments . 7 7.1 Sele

10、ction of monitors . 7 7.2 Introduction to the calibration of surface contamination instruments for direct measurement . 7 7.3 Tests before first use (TBFU) 8 7.4 Periodic calibration . 9 7.5 Function check 9 8 Estimation of surfac e c ontamination monit or r esponse and calibr ation fact ors.9 8.1 G

11、eneral . 9 8.2 Relationship between surface emission rate and activity 10 9 Evaluation of measurement data12 10 Uncertainties .12 10.1 General 12 10.2 Assessment of uncertainty in the calibration factor 12 10.3 Assessment of uncertainty in the measurement 13 10.4 Wipe test uncertainties .14 11 Test

12、report for a surface contamination instrument .14 Annex A (informative) Calibr ation of surfac e c ontamination instruments 16 Annex B (informative) Example of surface contamination estimation21 Annex C (informative) Calibr ation of dose r at e measuring instruments 23 Bibliogr aph y .25 ISO 2016 Al

13、l rights reserved iii Contents PageBS ISO 7503-1:2016ISO 7503-1:2016(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO tech

14、nical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely

15、 with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria nee

16、ded for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

17、 rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used i

18、n this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barri

19、ers to Trade (TBT) see the following URL: Foreword - Supplementary information The committee responsible for this document is ISO/TC 85, Nuclear energy nuclear technologies and radiological protection, Subcommittee SC 2, Radiation protection. This second edition cancels and replaces the first editio

20、n (ISO 7503-1:1988), which has been technically revised. ISO 7503 consists of the following parts, under the general title Measurement of radioactivity Measurement and evaluation of surface contamination: Part 1: General principles Part 2: Test method using wipe-test samples Part 3: Apparatus calibr

21、ationiv ISO 2016 All rights reservedBS ISO 7503-1:2016ISO 7503-1:2016(E) Introduction ISO 7503 gives guidance on the measurement of surface contamination. This International Standard is applicable to many situations where radioactive contamination can occur. Contamination arises from the release of

22、radioactivity into the local environment. In most circumstances, the release is inadvertent but, on occasion, may be deliberate. Although the purpose and scope of the investigation may differ, the approaches taken to measure the levels and extent of the contamination are essentially similar. Radioac

23、tive contamination can arise from a number of activities or events such as the following: routine laboratory use of radio-chemicals; medical treatments; industrial applications; transport accidents; equipment malfunctions; malevolent incidents; nuclear accidents. Without process knowledge or documen

24、tation, it is not always possible to identify or distinguish the different radionuclides constituting a surface contamination, and the evaluation of such a contamination cannot be made on a quantitative basis. Instead of using instruments with nuclide specific calibrations, it may be necessary to us

25、e other instruments which are fit for such a purpose. However, there may be cases (e.g. a contaminated fuel material transport container) where the radionuclide or the radionuclide mixture can be clearly characterized. A surface contamination evaluation exceeding a pure qualitative assessment of fix

26、ed and removable surface contamination may then be needed. Moreover, following requirements laid down in national regulations and in international conventions, a measured surface contamination activity per unit area has to be compared with surface contamination guideline values or surface contaminat

27、ion limits. Surface contamination guideline values are radionuclide-specific and thus require complex radionuclide-specific calibrations of measurement equipment. Calibration quality assurance is crucial in order to avoid non-detection (i.e. type II decision errors) leading to incorrectly assuming c

28、ompliance with given surface contamination guideline values or limits. Evaluation of surfaces contaminated by a mixture of radionuclides with known ratios requires respectively proportionated calibration factors. ISO 7503 is concerned with the measurement and estimation of radioactivity levels. It d

29、oes not provide advice on decommissioning, planning and surveillance techniques. Surface contamination is specified in terms of activity per unit area and the limits are based on the recommendations by the International Commission on Radiological Protection (ICRP 103). This part of ISO 7503 deals wi

30、th the evaluation of surface contamination by direct measurement using a surface contamination instrument, and in the case of the indirect method, using wipe tests. This part of ISO 7503 is primarily concerned with direct monitoring, practical guidance on measurements, it describes principles to kee

31、p an instrument in a fitness-for-purpose state. This part of ISO 7503 also presents instrument calibration principles and compiles the basic uncertainties of both surface contamination evaluation methods. ISO 2016 All rights reserved vBS ISO 7503-1:2016BS ISO 7503-1:2016Measurement of radioactivity

32、Measurement and evaluation of surface contamination Part 1: General principles 1 Scope ISO 7503 (all parts) and ISO 8769 are addressed to the people responsible for determining the radioactivity present on solid surfaces. ISO 7503 is published in three parts and can be used jointly or separately acc

33、ording to needs. This part of ISO 7503 relates to the assessment of surface contamination by direct and indirect measurements and the calibration of the associated instrumentation. The standard applies to alpha-, beta- and photon emitters and is intended for use by hospitals, universities, police, o

34、r industrial establishments. The standard also can be used in the assessment of activity on trucks, containers, parcels, equipment and is applicable in any organization which handles radioactive materials. Generally, it is applicable to well defined flat surfaces where direct methods are applicable,

35、 however, it can also be used for surfaces which are not flat and where indirect wipe tests would be appropriate. These investigations may be carried out on containers, inaccessible areas, non- flat areas where wipe tests can be used. This part of ISO 7503 may be useful in emergency situations, i.e.

36、 in nuclear accidents where health physics professionals would be involved. This part of ISO 7503 does not apply to the evaluation of contamination of the skin, of clothing and of loose material such as gravel. NOTE The test method using wipe-test samples for the evaluation of radioactive surface co

37、ntaminations is dealt with in ISO 7503-2. The calibration of instruments for the evaluation of radioactive surface contaminations is dealt with in ISO 7503-3. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for it

38、s application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 8769, Reference sources Calibration of surface contamination monitors Alpha-, beta- and photon emitters ISO 11929, Determ

39、ination of the characteristic limits (decision threshold, detection limit, and limits of the confidence interval) for measurements of ionizing radiation Fundamentals and application ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories INTERNATIONAL ST ANDARD

40、 ISO 7503-1:2016(E) ISO 2016 All rights reserved 1BS ISO 7503-1:2016ISO 7503-1:2016(E) 3 T erms a nd definiti ons, s ymbols and abb r e viations 3.1 T erms and definiti ons For the purposes of this document, the following terms and definitions apply. 3.1.1 activity per unit area ratio between the ac

41、tivity of the radionuclides present on a surface and the area of that surface, expressed in becquerels per square centimetre 3.1.2 surface contamination radioactive substances deposited on defined surfaces 3.1.3 f i x e d s u r f a c e c o n t a m i n a t i o n surface contamination which cannot be

42、removed or transferred by non-destructive means 3.1.4 r e m o v a b l e s u r f a c e c o n t a m i n a t i o n radioactive material that can be removed from surfaces by non-destructive means, including casual contact, wiping, or washing Note 1 to entry: It should be noted that under the influence o

43、f moisture, chemicals, etc., or as a result of corrosion or diffusion, fixed contamination may become removable or vice versa without any human action. Furthermore, surface contaminations may decrease due to evaporation and volatilization. Note 2 to entry: It should be emphasized that the ratio betw

44、een fixed and removable contamination can vary over time, and that some decisions, such as those related to clearance, should be based on total activity with the potential to become removable over time, not just the amount that is removable at the time of a survey. 3.1.5 direct measurement of surfac

45、e contamination measurement of surface contamination by means of a contamination meter or monitor 3.1.6 indirect evaluation of surface contamination evaluation of the removable surface contamination by means of a wipe test 3.1.7 wipe test test to determine if removable contamination is present throu

46、gh wiping the surface with a dry or wet material, followed by evaluation of the wipe material for removable contamination 3.1.8 w ipi n g ef f ic ienc y ratio of the activity of the radionuclides removed from the surface by one wipe sample to the activity of the radionuclides of the removable surfac

47、e contamination prior to this sampling Note 1 to entry: In practice, it is almost impossible to measure the total amount of removable activity on the surface, and in most cases, a value for the wiping efficiency cannot be assessed but can only be estimated. 3.1.9 surface emission rate of a source nu

48、mber of particles of a given type above a given energy or of photons emerging from the front face of the source per unit time2 ISO 2016 All rights reservedBS ISO 7503-1:2016ISO 7503-1:2016(E) 3.1.10 i n s t r u ment ef f ic ienc y ratio between the instrument net reading and the surface emission rat

49、e of a source under given geometrical conditions 3.1.11 emission instrument response instrument efficiency times detector window area, equals the observed net count rate per surface emission rate per unit area of a calibration source 3.1.12 activity instrument response instrument efficiency times detector window area times the probability of a particle or photon leaving the source surface, equals the observed net count rate per Bq per unit area of a calibration source 3.1.13 e m i s s ion c a l ibr at ion f ac t or