ASTM_D_3975_-_93_2014.pdf

Designation:D397593(Reapproved 2014)Standard Practice forDevelopment and Use(Preparation)of Samples forCollaborative Testing of Methods for Analysis of Sediments1This standard is issued under the fixed designation D3975;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 establishes uniform general procedures forthe development,(preparation)and use of samples in thecollaborative testing of methods for chemical analysis ofsediments and similar materials.1.2 The principles of this practice are applicable to aqueoussamples with suitable technical modifications.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:2D596 Guide for Reporting Results of Analysis of WaterD1129 Terminology Relating to WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD3670 Guide for Determination of Precision and Bias ofMethods of Committee D22D3976 Practice for Preparation of Sediment Samples forChemical AnalysisE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 DefinitionsFor definition of terms used in thispractice,refer to Terminology D1129.4.Summary of Practice4.1 Test samples of adequately defined composition andhomogeneity are required for evaluating the precision and biasof test methods.These samples should be typical in all respectsto the sample for which the test method is applicable.Sampleswith three levels of concentration of the measurand arerecommended to evaluate the linearity of the test method.Acceptable test materials,in order of preference are:threesamples of different compositions;mixtures of two samples toobtain the desired concentration levels;samples prepared bydilution of a single sample.4.2 In the absence of samples of known composition,theuse of the spiking technique,in which standard additions ofknown constituents are made by established techniques,will beacceptable for evaluating the linearity and the bias of testmethods.In such a case,the bias statement will consist of theaccuracy of recovery of the spike.4.3 Comparison of a candidate test method with a standardtest method of known precision and bias will constitute anacceptable technique for evaluation of precision and bias.Insuch comparative measurements,any convenient test samplesmay be used,provided they are shown to be stable during thetime required to make the intercomparison,and that themeasurement sequences are chosen to minimize or eliminateerrors due to sample instability.5.Significance and Use5.1 The objective of this practice is to provide guidelines forthe preparation of samples for use in collaborative tests,toevaluate methods during their development,and for the evalu-ation of the precision and bias of proposed test methods.5.2 Statements of the precision and bias are a mandatorypart of ASTM test methods.Such an evaluation is necessary toprovide guidance to the user as to the reliability of measure-ments that can be expected by its use.The statements aredeveloped on the basis of user experience(ordinarily collab-orative tests)with the test method.5.3 The availability of test samples is a key requirement forcollaborative evaluation of test methods.6.Rationale6.1 The use of materials of demonstrated adequate homo-geneity and known composition enable evaluation of theprecision and bias of a test method.Materials of known1This practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.07 on Sediments,Geomorphology,and Open-Channel Flow.Current edition approved Jan.1,2014.Published February 2014.Originallyapproved in 1980.Last previous edition approved in 2008 as D3975 93(2008).DOI:10.1520/D3975-93R14.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 composition are required to identify biases.Consensus valuesobtained as the result of collaborative testing are not adequateto permit quantitative evaluation of biases,although they mayshow that such exist.6.2 Materials of adequate homogeneity but uncertain com-position may be used to determine the precision of a given testmethod.Both single-laboratory precision or between operator-laboratory precision can