1、BSI Standards PublicationBS EN ISO 6142-1:2015Gas analysis Preparation ofcalibration gas mixturesPart 1: Gravimetric method for Class ImixturesBS EN ISO 6142-1:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 6142:2015. It supersedes BS EN ISO 6142:2006
2、which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee PTI/15, Natural Gas and Gas Analysis.A list of organizations represented on this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 provis
3、ions of a contract. Users are responsible for its correct application. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 76273 4 ICS 71.040.40 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was publish
4、ed under the authority of the Standards Policy and Strategy Committee on 30 September 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6142-1 September 2015 ICS 71.040.40 Supersedes EN ISO 6142:2006English Version
5、 Gas analysis - Preparation of calibration gas mixtures - Part 1: Gravimetric method for Class I mixtures (ISO 6142-1:2015) Analyse des gaz - Prparation des mlanges de gaz pour talonnage - Partie 1 : Mthode gravimtrique des mlanges Classe I (ISO 6142-1:2015) Gasanalyse - Herstellung von Kalibriergas
6、en - Teil 1: Wgeverfahren fr Gemische der Klasse I (ISO 6142-1:2015) This European Standard was approved by CEN on 5 September 2015. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national sta
7、ndard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in
8、any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Re
9、public, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPE
10、AN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 6142-1:2015 EB
11、S EN ISO 6142-1:2015EN ISO 6142-1:2015 (E) 3 European foreword This document (EN ISO 6142-1:2015) has been prepared by Technical Committee ISO/TC 158 “Analysisof gases“. This European Standard shall be given the status of a national standard, either by publication of anidentical text or by endorseme
12、nt, at the latest by March 2016, and conflicting national standards shallbe withdrawn at the latest by March 2016. Attention is drawn to the possibility that some of the elements of this document may be the subject ofpatent rights. CEN and/or CENELEC shall not be held responsible for identifying any
13、 or all such patentrights. This document supersedes EN ISO 6142:2006. According to the CEN-CENELEC Internal Regulations, the national standards organizations of thefollowing countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,Croatia, Cyprus, Czech Republic, Denmark,
14、Estonia, Finland, Former Yugoslav Republic of Macedonia,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,Turkey and the United Kingdom. Endorsement notice The
15、 text of ISO 6142-1:2015 has been approved by CEN as EN ISO 6142-1:2015 without anymodification. BS EN ISO 6142-1:2015ISO 6142-1:2015(E)Foreword vIntroduction vi1 Scope . 12 Normative references 13 Terms and definitions . 14 Symbols 25 Principle 36 Planning the preparation of the mixture 56.1 Feasib
16、ility of preparing the gas mixture . 56.1.1 Safety considerations . 56.1.2 Reactions of mixture components 56.1.3 Reactions with container materials . 56.2 Choice of preparation method . 56.3 Calculation of target masses 66.4 Condensation of components from the gas phase 67 Purity analysis . 68 Dete
17、rmination of masses and calculation of preparation uncertainty . 78.1 Preparation of cylinder 78.2 Determination of masses and their uncertainties 78.3 Atomic weights and molar masses 78.4 Calculation of the mixture composition 88.5 Calculation of gravimetric uncertainty 89 Homogeneity and stability
18、 of the calibration gas mixture . 89.1 Homogeneity . 89.2 Stability 99.2.1 General 99.2.2 Assessing stability 99.2.3 Statistics for assessment stability 119.2.4 Calculation of the preparation uncertainty .1110 Verification of calibration gas mixture composition .1110.1 Objectives 1110.2 Statistical
19、tests for consistency and uncertainty due to verification 1211 Uncertainty of the calibration gas mixture and preparation of certificate 12Annex A (informative) Precautions to be taken when weighing, handling and filling cylinders 14Annex B (informative) Practical examples 19Annex C (informative) Gu
20、idelines for estimating filling pressures so as to avoid condensation of condensable components in gas mixtures .22Annex D (normative) Liquid introduction .25Annex E (informative) Atomic weights and molar masses .32Annex F (informative) Derivation of the equation for calculating the calibration gas
21、mixture composition .34Annex G (informative) Sensitivity coefficients for the calculation of the uncertainty of the amount fraction of a component .36Annex H (informative) Derivation of the equation for the final measurement uncertainty on the calibration gas mixture 37 ISO 2015 All rights reserved
22、iiiContents PageBS EN ISO 6142-1:2015ISO 6142-1:2015(E)Bibliography .38iv ISO 2015 All rights reservedBS EN ISO 6142-1:2015ISO 6142-1:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of prepar
23、ing 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 organizations, governmental and non-governmental, in li
24、aison 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 its further maintenance are described in the ISO/IEC Di
25、rectives, 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 (see www.iso.org/directives).Attention is drawn to the possibility that
26、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 Introduction and/or on the ISO list of patent decl
27、arations received (see www.iso.org/patents).Any trade name used in 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 a
28、bout ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 158, Analysis of gases.This first edition of ISO 6142-1 cancels and replaces ISO 6142:2001, which has be
29、en technically revised to update the methods of preparation, estimation of the uncertainty, and validation of the composition of gravimetrically prepared calibration gases. It also incorporates the Amendment ISO 6142:2001/Amd.1:2009.ISO 6142 consists of the following parts, under the general title G
30、as analysis Preparation of calibration gas mixtures: Part 1: Gravimetric method for Class I mixturesA future part dealing with gravimetric method for Class II mixtures. ISO 2015 All rights reserved vBS EN ISO 6142-1:2015ISO 6142-1:2015(E)IntroductionThe revision of ISO 6142 was initiated to provide
31、better guidance to the users of this International Standard especially with respect to quality assurance measures and laboratory accreditation. In preparing the revision, it was decided to make accommodation for two types of calibration gas mixtures with different levels of quality assurance and wit
32、h different levels of measurement uncertainty. The difference in the two classes can be summarized as follows:Class I type calibration gas mixtures are prepared in accordance with this part of ISO 6142. The mixtures are individually verified. Provided rigorous and comprehensive quality assurance and
33、 quality control procedures are adopted during the preparation and verification of these mixtures, uncertainties may be achieved that are substantially smaller than by any other preparation method.Class II type calibration gas mixtures are prepared in a similar manner to Class I calibration gas mixt
34、ures but these mixtures are not individually verified. Verification of Class II calibration gas mixtures can be based on random verification checks. These checks are monitored by means of statistical quality control to be described in a future part. For mixtures containing identical compounds and no
35、minally identical amountofsubstance fractions, Class II type calibration gas mixtures will always have amountofsubstance fractions with larger uncertainties than their Class I counterparts.vi ISO 2015 All rights reservedBS EN ISO 6142-1:2015Gas analysis Preparation of calibration gas mixtures Part 1
36、 Gravimetric method for Class I mixtures1 ScopeThis part of ISO 6142 specifies a gravimetric method for the preparation of calibration gas mixtures in cylinders with traceable values for the amount-of-substance fraction (amount fraction) of one or more components. This part of ISO 6142 describes a
37、method for calculating the uncertainty associated with the amount fraction of each component. This uncertainty calculation requires the evaluation of the contributions to the uncertainty due to factors including the weighing process, the purity of the components, the stability of the mixture, and th
38、e verification of the final mixture.This part of ISO 6142 is only applicable to mixtures of gaseous or totally vaporized components, which may be introduced into the cylinder in the gaseous or liquid state. Both binary and multi-component gas mixtures (including natural-gas type mixtures) are covere
39、d by this part of ISO 6142. Methods for the batch production of more than one mixture in a single process are not included in this part of ISO 6142.This part of ISO 6142 requires estimation of the stability of the mixture for its intended life time (maximum storage life), but it is not for use with
40、components that react with each other unintentionally. This part of ISO 6142 also requires the impurities in each parent gas or liquid used in the preparation of the mixture to be assessed and quantified.2 Normative referencesThe following documents, in whole or in part, are normatively referenced i
41、n this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 6141, Gas analysis Contents of certificates for calibration gas mixturesISO 61
42、43, Gas analysis Comparison methods for determining and checking the composition of calibration gas mixturesISO 7504, Gas analysis VocabularyISO 14912, Gas analysis Conversion of gas mixture composition dataISO 16664, Gas analysis Handling of calibration gases and gas mixtures GuidelinesISO 19229, G
43、as analysis Purity analysis and the treatment of purity dataISO/TS 29041, Gas mixtures Gravimetric preparation Mastering correlations in compositionISO/IEC Guide 98-3, Uncertainty of measurement Part 3: Guide to the expression of uncertainty in measurement (GUM:1995)IUPAC, Commission on atomic weigh
44、ts and isotopic abundances: Atomic weights of the elements3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 7504 and ISO/IEC Guide 98-3 apply.INTERNATIONAL STANDARD ISO 6142-1:2015(E) ISO 2015 All rights reserved 1BS EN ISO 6142-1:2015ISO 6142-1:2015(E)
45、4 SymbolsAzatomic weight of element zbiestimated amount fraction drift rate of component ik coverage factorLijlimit of detection of impurity i in parent gas or liquid jMimolar mass of component iMjmolar mass of parent gas or liquid jMkmolar mass of component kMmolar mass of the final mixturemjmass a
46、dded of parent gas or liquid jmmass of the final mixtureq number of components in the mixturer number of parent gases or liquidspFfilling pressurepF,filling pressure of the final mixturepi(TL) saturated vapour pressure of component i at temperature TLR ideal gas constantTFfilling temperatureTLlowest
47、 temperature to which the gas mixture will be exposedtddecay timetsshelf life of the mixtureu(.) standard uncertainty (of the quantity in parentheses)U(.) expanded uncertainty (of the quantity in parentheses)Vcylvolume of the cylinderzistoichiometric coefficient for element zwimass fractions wiof th
48、e components i in the final mixturewi,jmass fraction of component i in parent gas or liquid jxcamount-of-substance fraction of the “pure” component in the material being analysedxiamount-of-substance fraction of component ixi,jamount-of-substance fraction of component i in parent gas or liquid jxk,j
49、amount-of-substance fraction of component k in parent gas or liquid jyk0amount-of-substance fraction of component k at time t = 02 ISO 2015 All rights reservedBS EN ISO 6142-1:2015ISO 6142-1:2015(E)yktamount-of-substance fraction of component k at time tyiamount-of-substance fraction of component i in the prepared mixtureykamount-of-substance fraction of component k in the prepared mixtureyk,veranalysed amount-of-substance fractioncompressibility of the final mixture final mixture5 PrincipleCalibration gas mixtures
