ASTM_E_2438_-_05.pdf

Designation:E 2438 05Standard Practice forImplementing Standard Performance Based Test Methodsfor the Analysis of Metals,Ores,and Related Materials1This standard is issued under the fixed designation E 2438;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice describes a model for use by analyticalchemistry laboratories in implementing standard performance-based test methods,such as those developed in accordancewith Practice E 2437.1.2 The principles in these practices can also be used byISO 17025 compliant laboratories that need to implement otherperformance-based test methods or need to document andvalidate extensions of standard test methods,or non-standardtest methods.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E 135 Terminology Relating to Analytical Chemistry forMetals,Ores,and Related MaterialsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE 1329 Practice for Verification and Use of Control Chartsin Spectrochemical AnalysisE 1601 Practice for Conducting an Interlaboratory Study toEvaluate the Performance of an Analytical MethodE 2027 Practice for Conducting Proficiency Tests in theChemical Analysis of Metals,Ores,and Related MaterialsE 2093 Guide for Optimizing,Controlling and ReportingTest method uncertainties from Multiple Workstations inthe Same Laboratory OrganizationE 2165 Practice for Establishing an Uncertainty Budget forthe Chemical Analysis of Metals,Ores,and RelatedMaterialsE 2437 Practice for Designing and Validating PerformanceBased Test Methods for the analysis of Metals,Ores,andRelated Materials2.2ISO Standards3ISO 17025 General Requirements for the Competence ofTesting and Calibration LaboratoriesISO Guide 32 Calibration in Analytical Chemistry and Useof Certified Reference MaterialsISO 5725 Precision of Test Results Determination ofrepeatability and reproducibility by interlaboratory tests3.Terminology3.1 DefinitionsFor definitions of terms used in the Prac-tice,refer to Terminology E 135.3.2 Definitions of Terms Specific to This Standard:3.2.1 aim total intralaboratory uncertainty,nthe maxi-mum deviation(95%confidence)to be allowed in the designof the total intralaboratory uncertainty of a test method,beginning with the preparation of a homogeneous sample andending with a final report value to the client.3.2.2 performance based method,na test method thatdefines(1)the general approaches for sampling,samplepreparation,and making measurements on a specified type ofmaterial,and,(2)defines maximum allowable uncertainties foreach measured constituent over its validated concentrationrange.3.2.3 total intralaboratory uncertainty,nin a performancebased standard test method,the precision(95%confidence)that a laboratory achieves when the method is used by morethan one operator.3.2.3.1 DiscussionIn test methods that establish maxi-mum allowable intralaboratory uncertainties,users must beable to demonstrate compliance with those uncertainties inorder to report that a given test result was produced using thenamed method.3.2.4 uncertainty budget,nthe allocation of total mea-surement uncertainty among specific components of a mea-surement process that contribute significantly to the overalldeviation.1This practice is under the jurisdiction of ASTM Committee E01 on AnalyticalChemistry for Metals,Ores,and Related Materials and is the direct responsibility ofSubcommittee E01.22 on Laboratory Quality.Current edition approved May 1,2005.Published July 2005.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036(www.ansi.org).1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.4.Significance and Use4.1 This practice is aimed at guiding analytical chemistrylaboratories through the implementation of ASTM standardperformance-based test methods in a manner that complieswith ISO 17025.The principles incorporated in this practicecan also be applied in laboratories that wish to extend theapplication of standard test methods beyond their publishedscopes or to validate and document non-standard methods.4.2 The major responsibilities described in this practiceinclude(1)writing an in-house standard o