1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI British StandardsWB9423_BSI_StandardColCov_noK_AW:BSI FRONT COVERS 5/9/08 12:55 Page 1Nuclear power plantsInstrumentation important to safety Radiation monitoring for accident and post-accident condi
2、tions Part 2: Equipment for continuous off-line monitoring ofradioactivity in gaseous effluents and ventilation airBS IEC 60951-2:2009National forewordThis British Standard is the UK implementation of IEC 60951-2:2009.The UK participation in its preparation was entrusted to Technical CommitteeNCE/8,
3、 Reactor instrumentation.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application. BSI 2009ISBN 978 0 580 68949 9ICS 13.28
4、0; 17.240; 27.120.20Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on 30 September 2009Amendments issued since publicationAmd. No. Date Text affectedBRITISH STANDARD
5、BS IEC 60951-2:2009IEC 60951-2Edition 2.0 2009-06INTERNATIONAL STANDARD NORME INTERNATIONALENuclear power plants Instrumentation important to safety Radiation monitoring for accident and post-accident conditions Part 2: Equipment for continuous off-line monitoring of radioactivity in gaseous effluen
6、ts and ventilation air Centrales nuclaires de puissance Instrumentation importante pour la sret Surveillance des rayonnements pour les conditions accidentelles et post-accidentelles Partie 2: Matriels pour la surveillance des rayonnements en continu avec prlvements dans les effluents gazeux et lair
7、de ventilation INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE QICS 27.120.20 PRICE CODECODE PRIXISBN 2-8318-1046-2 Registered trademark of the International Electrotechnical Commission Marque dpose de la Commission Electrotechnique Internationale BS IEC 60951-2:
8、2009 2 60951-2 IEC:2009 CONTENTS FOREWORD.3 INTRODUCTION.5 1 Scope.7 2 Normative references .7 3 Terms and definitions .8 4 Design principles8 4.1 General .8 4.2 Basic requirements related to functions.8 4.3 Sampling assembly .8 4.3.1 General .8 4.3.2 Measurement technique requirements .9 4.3.3 Requ
9、irements on filters and collecting devices 9 4.3.4 Requirements on sampling circuit and materials 10 5 Functional Testing 11 5.1 General .11 5.2 Reference sources 11 5.3 Performance characteristics : Response to other radioactive gases or particles 11 5.3.1 Requirements 11 5.3.2 Test method 11 5.4 A
10、ir circuit performance test12 5.4.1 General .12 5.4.2 Monitor sampling efficiency .12 5.4.3 Susceptibility to gas or particles retention13 5.4.4 Relative error of the volume and flow rate measurement .14 5.4.5 Flow-rate stability 15 5.4.6 Effect of filter pressure drop 15 5.4.7 Effect of power suppl
11、y voltage on the flow rate 15 5.4.8 Effect of power supply frequency on the flow rate 16 Table 1 Overview of the standards covering the domain of radiation monitoring.5 Table 2 Additional tests to complement the general tests required in IEC 60951-1.16 BS IEC 60951-2:200960951-2 IEC:2009 3 INTERNATI
12、ONAL ELECTROTECHNICAL COMMISSION _ NUCLEAR POWER PLANTS INSTRUMENTATION IMPORTANT TO SAFETY RADIATION MONITORING FOR ACCIDENT AND POST-ACCIDENT CONDITIONS Part 2: Equipment for continuous off-line monitoring of radioactivity in gaseous effluents and ventilation air FOREWORD 1) The International Elec
13、trotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields.
14、 To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC Na
15、tional Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization
16、(ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representatio
17、n from all interested IEC National Committees. 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot
18、be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications.
19、Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with an IEC Publ
20、ication. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, pro
21、perty damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications. 8) Attention is drawn to the Normative references cited in
22、 this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying an
23、y or all such patent rights. International Standard IEC 60951-2 has been prepared by subcommittee 45A: Instrumentation and control of nuclear facilities, of IEC technical committee 45: Nuclear instrumentation. This second edition cancels and replaces the first edition published in 1988, as well as I
24、EC 60951-5, published in 1994. This edition constitutes a technical revision. The main technical changes with regard to the previous edition are as follows: To clarify the definitions. To update the references to new standards published since the first issue. To update the units of radiation. BS IEC
25、 60951-2:2009 4 60951-2 IEC:2009 This standard is to be read in conjunction with IEC 60951-1. The text of this standard is based on the following documents: FDIS Report on voting 45A/735/FDIS 45A/757/RVDFull information on the voting for the approval of this standard can be found in the report on vo
26、ting indicated in the above table. This publication has been drafted in accordance with the ISO/IEC Directives, Part 2. A list of all parts of IEC 60951 series, under the general title Nuclear power plants Instrumentation important to safety Radiation monitoring for accident and post-accident condit
27、ions, can be found on the IEC website. The committee has decided that the contents of this publication will remain unchanged until the maintenance result date indicated on the IEC web site under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication wi
28、ll be reconfirmed, withdrawn, replaced by a revised edition, or amended. BS IEC 60951-2:200960951-2 IEC:2009 5 INTRODUCTION a) Technical background, main issues and organisation of the standard This IEC standard specifically focuses on radiation monitoring systems used for accident and post-accident
29、 operations. This standard is intended for use by purchasers in developing specifications for their plant-specific radiation monitoring systems and by manufacturers to identify needed product characteristics when developing systems for accident monitoring conditions. Some specific instrument charact
30、eristics such as measurement range, required energy response, and ambient environment requirements will depend upon the specific application. In such cases. guidance is provided on determining the specific requirements, but specific requirements themselves are not stated. This standard is one in a s
31、eries of standards covering post-accident radiation monitors important to safety. The full series is comprised of the following standards. IEC 60951-1 General requirements IEC 60951-2 Equipment for continuous off-line monitoring of radioactivity in gaseous effluents and ventilation air IEC 60951-3 E
32、quipment for continuous high range area gamma monitoring IEC 60951-4 Equipment for continuous in-line or on-line monitoring of radioactivity in process streams b) Situation of the current standard in the structure of the IEC SC 45A standard series The IEC 60951 series of standards are at the third l
33、evel in the hierarchy of SC 45A standards. They provide guidance on the design and testing of radiation monitoring equipment used for accident and post-accident conditions. Other standards developed by SC 45A and SC 45B provide guidance on instruments used for monitoring radiation as part of normal
34、operations. The IEC 60761 series provide requirements for equipment for continuous off-line monitoring of radioactivity in gaseous effluents in normal conditions. IEC 60861 provides requirements for equipment for continuous off-line monitoring of radioactivity in liquid effluents in normal condition
35、s. IEC 60768 provides requirements for equipment for continuous in-line and on-line monitoring of radioactivity in process streams in normal and incident conditions. Finally, ISO 2889 gives guidance on gas and particulate sampling. The relationship between these various radiation monitoring standard
36、s is given in Table 1 below. Table 1 Overview of the standards covering the domain of radiation monitoring Developer ISO SC 45A Process and safety monitoring Scope Sampling circuits and methods Accident and post-accident conditions Normal and incident conditions SC 45B Radiation protection and efflu
37、ents monitoring Gas, particulate and iodine with sampling (OFF LINE) ISO 2889 IEC 60951-1 and IEC 60951-2 IEC 60761 series and IEC 62302 (noble gases only) Liquid with sampling (OFF LINE) N/A N/A IEC 60861 Process streams (gaseous effluents, steam or liquid) without sampling (ON or IN-LINE) N/A IEC
38、60951-1 and IEC 60951-4 IEC 60768 N/A Area monitoring N/A IEC 60951-1 and IEC 60951-3 IEC 60532 BS IEC 60951-2:2009 6 60951-2 IEC:2009 Developer ISO SC 45A Process and safety monitoring Scope Sampling circuits and methods Accident and post-accident conditions Normal and incident conditions SC 45B Ra
39、diation protection and effluents monitoring Central system N/A IEC 61504 IEC 61559 series For more details on the structure of the IEC SC 45A standard series, see item d) of this introduction. c) Recommendations and limitations regarding the application of this standard It is important to note that
40、this Standard establishes no additional functional requirements for safety systems. d) Description of the structure of the IEC SC 45A standard series and relationships with other IEC documents and other bodies documents (IAEA, ISO) The top-level document of the IEC SC 45A standard series is IEC 6151
41、3. It provides general requirements for I noble gas, aerosol and specific nuclide (commonly iodine, in its different forms: inorganic iodine, organic iodine and iodine sticking on dust) monitors intended to measure the volumetric activity in air or gas systems (control room ventilation, reactor leak
42、age collection, drywell ventilation exhaust, fuel handling building ventilation exhaust, reactor building ventilation purge exhaust) and detect any significant increase of radioactivity during or after an accident. This standard is only applicable to continuous off-line measurement, i.e. monitors wh
43、ose detector measures a representative proportion of the main effluent or ventilation stream at some remote location (sampling assembly). It does not apply to monitors with the detector positioned in or adjacent to the effluent or ventilation stream, which are within the scope of IEC 60951-4. Sample
44、 extraction and laboratory analysis, which are essential to a complete programme of effluent monitoring, are not within the scope of this standard. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition
45、 cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60951-1:2009, Nuclear power plants Instrumentation important to safety Radiation monitoring for accident and post-accident conditions Part 1: General requirements IEC 61226,
46、Nuclear power plants Instrumentation and control systems important to safety Classification of instrumentation and control functions BS IEC 60951-2:2009 8 60951-2 IEC:2009 ISO 2889:2009, Sampling airborne radioactive materials from the stacks and ducts of nuclear facilities 3 Terms and definitions F
47、or the purposes of this document, the terms and definitions given in IEC 60951-1 apply. 4 Design principles 4.1 General The general requirements of IEC 60951-1 are applicable to all types of monitors within the scope of the present standard, unless otherwise stated. 4.2 Basic requirements related to
48、 functions The equipment will typically measure levels of activity in engineered gaseous discharge routes, such as reactor or fuel handling buildings, and ventilation ducts and stacks. It is intended to provide, depending on the required function, a measure of activity discharged to the environment
49、or detection and quantification of leakage in containment barriers, and any useful information on the behaviour of the plant, which causes or allows the activity release. The measurement of activity discharge to the environment should ideally be comprehensive, but since measurement of halogen and particulate activity released in effluents during an accident is more complex, it is often judged that monitoring only noble gases will be suffic
