1、BSI Standards PublicationBS ISO 19238:2014Radiological protection Performance criteria for servicelaboratories performingbiological dosimetry bycytogeneticsBS ISO 19238:2014 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 19238:2014. Itsupersedes BS ISO 19238:2
2、004 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee NCE/2, Radiation protection and measurement.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessa
3、ryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2014. Published by BSI StandardsLimited 2014ISBN 978 0 580 72916 4ICS 13.280; 17.240Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard wa
4、s published under the authority of theStandards Policy and Strategy Committee on 28 February 2014.Amendments issued since publicationDate Text affectedBS ISO 19238:2014 ISO 2014Radiological protection Performance criteria for service laboratories performing biological dosimetry by cytogeneticsRadiop
5、rotection Critres de performance pour les laboratoires de service pratiquant la dosimtrie biologique par cytogntiqueINTERNATIONAL STANDARDISO19238Second edition2014-02-01Reference numberISO 19238:2014(E)BS ISO 19238:2014ISO 19238:2014(E)ii ISO 2014 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO
6、 2014All 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 requ
7、ested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 19238:2014ISO 19238:2014(E) ISO 2014 All
8、 rights reserved iiiContents PageForeword vIntroduction vi1 Scope . 12 Terms and definitions . 13 Dicentric assay 34 Responsibility of the customer 35 Responsibility of the service laboratory 45.1 Setup and sustainment of the QA program . 45.2 Responsibility during service . 46 Confidentiality of pe
9、rsonal information 56.1 Overview 56.2 Applications of the principle of confidentiality 57 Laboratory safety requirements 67.1 Overview 67.2 Microbiological safety requirements . 67.3 Chemical safety . 67.4 Optical safety requirements 87.5 Safety plan . 88 Calibration curve(s) 98.1 Culturing . 98.2 C
10、alibration source(s) 108.3 Establishment of calibration curve(s) . 108.4 Minimum resolvable dose measurement 119 Scoring unstable chromosome aberrations 119.1 Procedure for scoring first-division metaphases .119.2 Criteria for scoring 1110 Criteria for converting a measured aberration frequency into
11、 an estimate of absorbed dose 1210.1 Overview . 1210.2 Comparison with controls 1210.3 Testing the distribution of aberrations per cell .1210.4 Determination of estimated whole-body dose and confidence limits .1210.5 Acute and non-acute exposure cases 1310.6 Partial-body and prior-exposure cases . 1
12、311 Reporting of results 1511.1 General 1511.2 Content of the report (see Annex C for a standard form) .1511.3 Interpretation of the results .1612 Quality assurance and quality control 1612.1 Overview .1612.2 Specific requirements 17Annex A (informative) Sample instructions for customer 19Annex B (i
13、nformative) Sample questionnaire .20Annex C (informative) Sample of report 22Annex D (informative) Fitting of the low-LET dose-response curve by the method of maximum likelihood and calculating the error of dose estimate .23Annex E (informative) Odds ratio method for cases of suspected exposure to a
14、 low dose .26BS ISO 19238:2014ISO 19238:2014(E)iv ISO 2014 All rights reservedAnnex F (informative) Sample data sheet for recording aberrations .27Bibliography .28BS ISO 19238:2014ISO 19238:2014(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national
15、standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical 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
16、 organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for
17、 its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed 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. www.iso.org/dir
18、ectivesAttention is drawn to the possibility that some of the elements of this document may be the subject of patent 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
19、Introduction and/or on the ISO list of patent declarations received. www.iso.org/patentsAny trade name used in this document is information given for the convenience of users and does not constitute an endorsement.The committee responsible for this document is ISO/TC 85, Nuclear energy, nuclear tech
20、nologies, and radiological protection, Subcommittee SC 2, Radiological protection.This second edition cancels and replaces the first edition (ISO 19238:2004), of which it constitutes a minor revision. ISO 2014 All rights reserved vBS ISO 19238:2014ISO 19238:2014(E)IntroductionThe wide use of ionisin
21、g radiations for medical, industrial, agricultural, research, and military purposes increases the risk of overexposure of radiation workers and individuals of the general population. Biological dosimetry, based on the study of chromosomal aberrations, mainly the dicentric assay, has become a routine
22、 component of accidental dose assessment. Experience with its application in hundreds of cases of suspected or verified overexposures has proved the value of this method and also defined its limitations. It should be emphasized that cytogenetic analysis is used as a dosimeter and provides one input
23、into the compendium of information needed for assessment of a radiological accident.Many studies in animals and man have shown that one can establish a good correlation between the results obtained in vivo and in vitro, so that in vitro established dose-effect relationships from irradiated blood sam
24、ples can be used as calibration curves. The dicentric yield is dependent on radiation quality and dose rate so that information about these variables needs to be established for each investigation. If known, these exposure characteristics are important for refining the dose estimates. The specificit
25、y of this technique is enhanced by the fact that generally 1 dicentric is observed per 1 000 metaphase spreads in the normal population, and that this frequency is approximatively independent of age and sex. The precision of the technique thus depends on the number of cells observed, the background
26、level, and the calibration curve used. Theoretically, it is possible to detect exposure as low as 0,01 Gy. However, for these very low doses, it is necessary to analyse tens of thousands of metaphase spreads. In practice, this level of detection is neither feasible nor necessary. The upper limits to
27、 dose detection extend well into the range of doses that are lethal to humans.The primary purpose of this International Standard is to provide a guideline to all laboratories in order to perform the dicentric assay using documented and validated procedures. Secondly, it can facilitate the comparison
28、 of results obtained in different laboratories, particularly for international collaborations or intercomparisons. Finally, laboratories newly commissioned to carry out the dicentric assay should conform to this International Standard in order to perform it reproducibly and accurately.This Internati
29、onal Standard is written in the form of procedures to be adopted for biological dosimetry for overexposures involving, at most, a few casualties. The criteria required for such measurements will usually depend upon the application of the results: radiation protection management, medical management w
30、hen appropriate, record keeping, and legal requirements. In the special situation of a mass radiation casualty and limited resources, the technique can be applied for emergency triage analysis. The standard recommended scoring criteria would then be relaxed as appropriate to the situation.A part of
31、the information in this International Standard is contained in other international guidelines and scientific publications, primarily in the International Atomic Energy Agencys (IAEA) Technical Reports Series on Biological Dosimetry. However, this International Standard expands and standardizes the q
32、uality assurance and quality control, the criteria of accreditation, and the evaluation of performance. This International Standard is generally compliant with ISO/IEC 17025, with particular consideration given to the specific needs of biological dosimetry. The expression of uncertainties in dose es
33、timations given in this International Standard comply with the ISO guide to the expression of uncertainty in measurement (ISO/IEC Guide 98-1) and the ISO 5725 on accuracy (trueness and precision) of measurement methods and results.vi ISO 2014 All rights reservedBS ISO 19238:2014Radiological protecti
34、on Performance criteria for service laboratories performing biological dosimetry by cytogenetics1 ScopeThis International Standard provides criteria for quality assurance and quality control, evaluation of the performance, and the accreditation of biological dosimetry by cytogenetic service laborato
35、ries.This International Standard addressesa) the confidentiality of personal information, for the customer and the service laboratory,b) the laboratory safety requirements,c) the calibration sources and calibration dose ranges useful for establishing the reference dose-effect curves that contribute
36、to the dose estimation from chromosome aberration frequency and the minimum resolvable doses,d) the scoring procedure for unstable chromosome aberrations used for biological dosimetry,e) the criteria for converting a measured aberration frequency into an estimate of absorbed dose,f) the reporting of
37、 results,g) the quality assurance and quality control,h) informative annexes containing sample instructions for customer, sample questionnaire, sample of report, fitting of the low dose-response curve by the method of maximum likelihood and calculating the error of dose estimate, odds ratio method f
38、or cases of suspected exposure to a low dose, and sample data sheet for recording aberrations.2 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.2.1acentricterminal or interstitial chromosome fragment of varying size, referred to as an excess acentric
39、 fragment when it is formed independently of a dicentric or centric ring chromosome aberration2.2background levelspontaneous frequency (or number) of chromosome aberrations recorded in control samples or individuals2.3biasstatistical sampling or testing error caused by systematically favouring some
40、outcomes over others2.4centric ringaberrant circular chromosome resulting from the joining of two breaks on separate arms of the same chromosomeNote 1 to entry: It is generally accompanied by an acentric fragment.INTERNATIONAL STANDARD ISO 19238:2014(E) ISO 2014 All rights reserved 1BS ISO 19238:201
41、4ISO 19238:2014(E)2.5centromerespecialized constricted region of a chromosome that appears during mitosis and joins together the chromatid pair2.6confidence intervalstatistical range about an estimated quantity within which the value of the quantity is expected to occur, with a specified probability
42、2.7chromosomestructure that comprises discrete packages of DNA and proteins that carries genetic information which condense to form characteristically shaped bodies during nuclear division2.8chromatideither of the two strands of a duplicated chromosome that are joined by a single centromere and sepa
43、rate during cell division to become individual chromosomes2.9dicentricaberrant chromosome bearing two centromeres derived from the joining of parts from two broken chromosomesNote 1 to entry: It is generally accompanied by an acentric fragment.2.10FISHfluorescence in situ hybridizationtechnique that
44、 uses specific sequences of DNA as probes to particular parts of the genome, allowing the chromosomal regions to be highlighted or “painted” in different colours by attachment of various fluorochromes2.11interphaseperiod of a cell cycle between the mitotic divisions2.12LETlinear energy transferquoti
45、ent of dE/dl, as defined by the International Commission on Radiation Units and Measurements (ICRU), where dE is the average energy locally imparted to the medium by a charged particle of specific energy in traversing a distance of dl2.13lower threshold of dosesmallest measurable amount (e.g. freque
46、ncy or dose) that is detected with a probability of non-detection (Type II error) while accepting a probability of erroneously deciding that a positive (non-zero) quantity is present in an appropriate background sample (Type I error)2.14metaphasestage of mitosis when the nuclear membrane is dissolve
47、d, the chromosomes condensed to their minimum lengths and aligned for division2.15minimum resolvable doselowest additional dose for which the lower 95 % Poisson confidence limit is greater than 0, so that there is a 97,5 % chance that the dose received in excess of normal background is greater than
48、02 ISO 2014 All rights reservedBS ISO 19238:2014ISO 19238:2014(E)2.16precisionconcept employed to describe dispersion of measurements with respect to a measure of location or central tendency2.17quality assuranceplanned and systematic actions necessary to provide adequate confidence that a process,
49、measurement, or service satisfies given requirements for quality in, for example, those specified in a licence2.18quality controlpart of quality assurance intended to verify that systems and components conform to predetermined requirements2.19service laboratorylaboratory performing biological dosimetry measurements3 Dicentric assayThe frequency of unstable chromosomal aberrations seen at metaphase in cultured human peripheral blood lymphocytes is the recommended method for biological dosimetry. The chromosome aberrations to be used are dicentrics
