ASTM_D_6607_-_00_2015.pdf

Designation:D660700(Reapproved 2015)Standard Practice forInclusion of Precision Statement Variation in SpecificationLimits1This standard is issued under the fixed designation D6607;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()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers a method of determining rationalspecification limits by inclusion of the precision of the testmethod used in the specification.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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:2C670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC802 Practice for Conducting an Interlaboratory Test Pro-gram to Determine the Precision of Test Methods forConstruction MaterialsD2172 Test Methods for Quantitative Extraction of BitumenFrom Bituminous Paving MixturesD2726 Test Method for Bulk Specific Gravity and Densityof Non-Absorptive Compacted Bituminous MixturesE177 Practice for Use of the Terms Precision and Bias inASTM Test Methods2.2 Federal Highway Administration Report:FHWAReportHI-93047 MaterialsControlandAcceptanceQuality Assurance,FederalHighwayAdministration,May 199333.Terminology3.1 For definitions of terms used in this practice,consultPractice E177.4.Significance and Use4.1 Each test method has a limited precision.Even if a testis performed as carefully and as correctly as possible on amaterial which is as homogeneous as can be obtained,the testwill still vary from one to another.A widely used measure ofthe variation of the test results from a test method is thestandard deviation().In an ASTM standard test,the standarddeviation of the test method can be found in the Precision andBias statement for the test.The“Blue Book,”Form and Stylefor ASTM Standards,requires that all test methods includePrecision and Bias statements.Practice C670 and PracticeC802 provide guidance for determination of these values.4.2 If the precision of a test method is low and the precisionof the test has not been properly considered in a materialspecification,a uniform material with the right quality may stillbe rejected most of the time because of the wide variation ofthe test results.In order to have rational specification limits,theprecision of the test used should be properly included in aspecification.4.3 This practice provides a guideline for proper inclusionof precision of the test method in a rational specification.5.Procedure5.1 Determine the effective standard deviation(X)of thetest results due to the combined effects of materials variationand test variation using Eq 1:X5M21T2!(1)where:M=standard deviation of test property due to materialvariation(see Note 1),andT=standard deviation of test property due to test method(see Note 2).NOTE1Mis the expected standard deviation of the material propertywhen the material is produced in a properly controlled process.Astandarddeviation which is representative of the acceptable variation of thematerial can be used.It can be calculated from the data obtained fromproperly produced materials.1This practice is under the jurisdiction of Committee D04 on Road and PavingMaterials and is the direct responsibility of Subcommittee D04.94 on StatisticalProcedures and Evaluation of Data.Current edition approved Jan.1,2015.Published February 2015.Originallyapproved in 2000.Last previous edition approved in 2009 as D6607 00(2009).DOI:10.1520/D6607-00R15.2For 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 National Technical Information Service(NTIS),U.S.Depart-ment of Commerce,5285 Port Royal Rd.,Springfield,VA 22161.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 NOTE2Tis the standard deviation as given in the precision statementfor the test method used to measure the test property.5.2 Determine the standard deviation of the mean of the testresults3!using Eq 2:35 3/=n(2)where:n=number of tests performed.5.3 For a two-ended specification(with both a minimumand maximum limits),the specification limits for the averagetest value from n testx!should be the following:2 Z/23#3#1Z/23(3)where:=target propertyZ/2=critical number of standard deviations for(1)con-fidence interval.(See Table 1 for values of Z/2fordifferent specified c