1、BRITISH STANDARD BS EN 60761-5:2004 Incorporating Amendment No. 1 to BS IEC 60761-5:2002 (renumbers the BS IEC as BS EN 60761-5:2004) Equipment for continuous monitoring radioactivity in gaseous effluents Part 5: Specific requirements for tritium monitors The European Standard EN 60761-5:2004 has th
2、e status of a British Standard ICS 13.280 BS EN 60761-5:2004 This British Standard, having been prepared under the direction of the Engineering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 4 December 2002 BSI 10 March 2005
3、ISBN 0 580 40882 5 National foreword This British Standard is the official English language version of EN 60761-5:2004. The CENELEC common modifications have been implemented at the appropriate places in the text. The start and finish of each common modification is indicated in the text by tags . Wh
4、ere a common modification has been introduced by amendment, the tags carry the number of the amendment. For example, the common modifications introduced by CENELEC amendment A11 are indicated by . The UK participation in its preparation was entrusted to Technical Committee NCE/2, Health physics inst
5、rumentation, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogu
6、e under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correc
7、t application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests infor
8、med; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 16, the Annex ZA page and a back cover. The BSI copyright notice displayed in this document indicat
9、es when the document was last issued. Amendments issued since publication Amd. No. Date Comments 15423 10 March 2005 Implementation of the European StandardEUROPEAN STANDARD EN 60761-5 NORME EUROPENNE EUROPISCHE NORM December 2004 CENELEC European Committee for Electrotechnical Standardization Comit
10、 Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2004 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60761-5:2004 E ICS 13.280
11、English version Equipment for continuous monitoring radioactivity in gaseous effluents Part 5: Specific requirements for tritium monitors (IEC 60761-5:2002, modified) Equipements de surveillance en continu de la radioactivit dans les effluents gazeux Partie 5: Exigences particulires aux moniteurs de
12、 tritium (CEI 60761-5:2002, modifie) Einrichtungen zur kontinuierlichen berwachung von Radioaktivitt in gasfrmigen Ableitungen Teil 5: Besondere Anforderungen an Tritiummonitore (IEC 60761-5:2002, modifiziert) This European Standard was approved by CENELEC on 2004-11-01. CENELEC members are bound to
13、 comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Centra
14、l Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same stat
15、us as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Sl
16、ovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. NE 067-165:2004 2 Foreword The text of the International Standard IEC 60761-5:2002, prepared by SC 45B, Radiation protection instrumentation, of IEC TC 45, Nuclear instrumentation, together with the common modifications prepared by the
17、 CENELEC BTTF 111-3 Instrumentation for ionizing radiation measurement and protection, was submitted to the formal vote and was approved by CENELEC as EN 60761-5 on 2004-11-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an id
18、entical national standard or by endorsement (dop) 2005-11-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2007-11-01 Annex ZA has been added by CENELEC. _ Page2 EN607615:2004-167062002:CEI 5 5 EQUIPMENT FOR CONTINUOUS MONITORING OF RADIOACTIVITY IN G
19、ASEOUS EFFLUENTS Part 5: Specific requirements for tritium monitors 1 Scope and object This part of IEC 60761 is applicable to equipment intended for the simultaneous, delayed or discrete sequential measurement of tritium in any gaseous form in gaseous effluents dis- charged into the environment. It
20、 is applicable to equipment designed to fulfill the following functions: the measurement of the concentration of tritium in the gaseous effluents at the discharge point and its variation with time; the actuation of an alarm when a predetermined volumic activity or a predetermined total released radi
21、oactivity is exceeded. The equipment may also be used for the determination of the tritium activity discharge over a given period. The object of this standard is to establish specific standard requirements, including technical characteristics and general test conditions and to give examples of accep
22、table methods for the tritium effluent monitors defined in clause 4. The general requirements, technical characteristics, test procedures, radiation characteristics, electrical, mechanical, safety and environmental characteristics are given in IEC 60761-1. Unless otherwise stated, these requirements
23、 apply in this standard. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of IEC 60761. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. Howeve
24、r, parties to agreements based on this part of IEC 60761 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of IEC and ISO mai
25、ntain registers of currently valid International Standards. IEC 60068-2-27:1987, Environmental testing Part 2: Tests. Test Ea and guidance: Shock IEC 60761-1:2002, Equipment for continuous monitoring of radioactivity in gaseous effluents Part 1: General requirements IEC 61000 (all parts), Electromag
26、netic compatibility (EMC) EN 55022:1994, Limits and Methods of Measurement of Radio Disturbance Characteristics of Information Technology Equipment Page3 EN607615:2004-167062002:CEI 5 6 3 Terms and definitions For the purpose of this part of IEC 60761, the following definitions apply: 3.1 tritium ef
27、fluent monitor equipment designed for the continuous monitoring of tritium in gaseous effluents discharged to the environment 3.2 tritium unless otherwise stated, “tritium“, in this standard, covers tritium in gaseous or vapour forms, whether chemically combined or not 4 Classification of tritium ef
28、fluent monitors The equipment may be classified according to the type of measurement as: selective monitors, for the selective measurement of one particular form of tritium (gas, tritium oxide or any tritiated compound); non-selective monitors, for the overall measurement of tritium in all its forms
29、. 5 Sampling and detection assembly 5.1 Sampling and exhaust pipes In addition to the general requirements of IEC 60761-1, the following characteristics shall be considered and shall be agreed between manufacturer and purchaser: the nature of the materials used, paying particular attention to chemic
30、al corrosion, electrostatic effects, memory effects, etc.; the minimum distance between inlet and outlet to avoid recirculation; the prevention of condensation in the pipe by variation of temperature or pressure; the ease of decontamination. 5.2 Inlet filter A filter shall be placed in a filter-hold
31、er at the sampling circuit inlet to remove any dust and aerosols from the air. In order to maintain the specified performance of the equipment, such a filter shall not trap, or even temporarily, retain tritium. All necessary arrangements shall be made to control the pressure drop in the filter. The
32、system should be designed to allow filter change at a given pressure drop to ensure that an intact filter is in place. 5.3 Ease of decontamination In order to avoid interference with measurements, it is recommended that all necessary arrangements be made to limit the contamination of the detector. I
33、n all cases, the detection assembly shall be easy to dismantle, decontaminate and reassemble. Page4 EN607615:2004-167062002:CEI 5 7 5.4 Collection medium If the detection assembly includes an absorbent medium, intended to collect a specific chemical form of tritium, its characteristics, efficiency,
34、retention capacity and delay time constant shall be known for the various radioactive gases of significance in the effluent. The manufacturer shall state how the collection efficiency is influenced by the chemical form of tritium, atmospheric conditions and the presence of chemical products and othe
35、r gases in sampled air. The manufacturer shall specify the storage conditions of the absorbent medium. 5.5 Check source Any check source, when not in use, shall not increase the reading of the measurement assembly by more than 10 % of the maximum value of the lowest useful decade of measurement. 5.6
36、 Air pump The requirement of clause 11 of IEC 60761-1 is applicable. 5.7 Radiation detector The manufacturer shall specify the detector characteristics, including the detector dimensions and sampling volume. 6 Expression of measurements In accordance with the requirements of clause 9 of IEC 60761-1,
37、 the electronic assembly associated with the detector shall provide a reading expressed directly in terms of volumic activity (Bq/m 3 ). 7 Tests performed under standard test conditions Except where otherwise specified, tests are to be considered as type tests, although any or all may be considered
38、as acceptance tests by agreement between manufacturer and purchaser. The standard test conditions are shown in Table 1. These represent the values and tolerances of the various influence quantities for tests carried out with no variation of these values. The tests carried out under standard test con
39、ditions are listed in Table 2. 8 Tests performed with variation of the influence quantities These tests are listed in Tables 3 and 4. They shall be carried out in accordance with clause 24 of IEC 60761-1. Page5 EN607615:2004-167062002:CEI 5 8 9 Reference sources For the determination of the referenc
40、e response during type tests, the reference source shall be air with a known volumic activity of the particular form of tritium for which the equipment is designed. The reference sources should consist of bottles of pressurized air or gas containing the form of tritium for which the equipment is des
41、igned or any other calibrated device generating the appropriate form of tritium. Some suitable means of producing sources are described in annex A. The conventionally true activity of the gas sources shall be known with an uncertainty better than 7 % (k = 2). 10 Radiation performance tests These tes
42、ts are carried out under standard test conditions. If an electronic method of compensation against natural activity is included, all tests of the measuring assembly shall be performed with the compensation circuits in operation, after having been adjusted according to the manufacturers instructions.
43、 10.1 Reference response 10.1.1 Requirements The reference response shall not differ by more than 15 % from the manufacturers speci- fications. 10.1.2 Test method Circulate air, labelled with a known volumic activity of tritium, through the assembly at a constant flow-rate, for a time sufficient to
44、reach measurement equilibrium. Note the equilibrium reading. Some methods are given as examples in annex A. 10.2 Linearity The requirements and test methods described in 26.3 of IEC 60761-1 are applicable. 10.3 Response to other chemical forms of tritium 10.3.1 Requirements If the equipment is desig
45、ned to measure the activity of a particular chemical form of tritium, its response to other chemical forms having an influence on the measurement shall be specified by the manufacturer, and shall be less than 15 % of the response to the form of tritium for which the equipment is designed. 10.3.2 Tes
46、t method The test method is identical with that described in 10.1.2, but using other chemical forms of tritium. 10.4 Response to radioactive gases other than tritium 10.4.1 Requirements The manufacturer shall state the response of the equipment to designated radioactive gases other than tritium. The
47、 designated radioactive gases to which this requirement is applied shall be the object of an agreement between the manufacturer and the purchaser. Page6 EN607615:2004-167062002:CEI 5 9 10.4.2 Test method The test method is identical with that described in 10.1.2, but using the appropriate radioactiv
48、e gas or gases. 10.5 Response time 10.5.1 Requirements The manufacturer shall specify the response time of the assembly. The response time includes the renewal time of the air in the detector. 10.5.2 Test method This test shall be carried out at the nominal flow-rate. The volumic activity inside the
49、 chamber has to be at least 10 times the decision threshold. A recorder shall be connected to the assembly to determine the change in indication as a function of time. Two methods may be used: Option 1: Inject continuously into the inlet of the monitor a known volumic activity of tritium for the time needed to reach the equilibrium. Note the equilibrium value R f . Option 2: Connect the input of the ai
