1、Designation: D 6362 98 (Reapproved 2008)Standard Practice forCertificates of Reference Materials for Water Analysis1This standard is issued under the fixed designation D 6362; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the yea
2、r 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 the information that must beprovided on certificates of analysis of reference materialsdesig
3、nated to support ASTM methods. It provides end users ofthese materials with a defined set of data that is required to beon a certificate of analysis and provides information to assistthe end user in evaluating the independence of the material.Similarly, it provides the suppliers of reference materia
4、ls witha consistent format for the presentation of certification data.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.
5、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:2D 1129 Terminology Relating to WaterE 826 Practice for Testing Homogeneity of
6、a Metal Lot orBatch in Solid Form by Spark Atomic Emission Spectrom-etry2.2 ISO Standards3ISO Guide 30 Terms and definitions used in connection withreference materialsISO Guide 31 Contents of certificates of reference materialsISO Guide 35 Certification of reference materialsGeneraland statistical p
7、rinciplesISO/REMCO N2803. Terminology3.1 DefinitionsFor definitions of terms used in this prac-tice, refer to Terminology D 1129 and ISO Guide 303.2 Definitions of Terms Specific to This Standard:3.2.1 prepared value, nthe best estimate of the concen-tration of a given analyte based upon the purity
8、of rawmaterials and the method of preparation of the material.4. Significance and Use4.1 This practice is designed to assist suppliers and users ofreference materials by identifying the information necessary onthe certificate of analysis of materials designated for use inASTM test methods. This prac
9、tice is specifically designed toensure that materials suitable for use as either calibration orquality control standards are available. This practice does notdefine a specific certification protocol, but rather providesguidance in the development of adequate data to support theuse of the material as
10、 either a calibration or quality controlstandard. Suppliers are referred to ISO Guide 35 for guidelineson acceptable certification protocols. End users are referred toISO Guide 31 for a more complete description of the elementsof typical certificates of analysis.5. Certificate of Analysis5.1 The cer
11、tificate of analysis is a summary of the analysisperformed to support the designated use of the material. As asummary, the certificate must be brief, but it must providesufficient information to allow the potential user of the materialto assess the suitability of the material for his intended use.1T
12、his practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.02 on Quality Systems, Specifi-cation, and Statistics.Current edition approved July 15, 2008. Published August 2008. Originallyapproved in 1998. Last previous edition approved in
13、 2003 as D 6362 98 (2003).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 S
14、tandards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Therefore, reference material suppliers are encouraged tosupply method information and analyt
15、ical data in a summarythat clearly and unambiguously allows the user to make aninformed decision about the suitability of the material. The useof terms as defined by ISO or ASTM is required.5.2 The certificate of analysis must be supported by acertification report for the material. The certification
16、 reportmust contain the details of the analyses performed to developthe certified values reported on the certificate of analysis. Itmust contain the method(s) used for analysis, details of themethod of preparation, if appropriate, including gravimetricdata, supporting instrumental data, and the resu
17、lts of support-ing statistical analysis reported on the certificate of analysis.The certification report must be provided to the end user of thematerial if requested.6. Certificate Headings6.1 The following sections detail the headings to be used onthe certificate of analysis. ASTM methods require t
18、he use of adiverse set of reference materials. Therefore, it is expected thatall headings will not be appropriate for all materials. However,exceptions should be avoided in order to insure sufficientinformation for evaluation of materials. Therefore, each of thefollowing sections is designated as ei
19、ther mandatory or op-tional based upon ensuring a minimum data set. Appendix X1contains examples of typical certificates of analysis designed tomeet these requirements.6.1.1 Name and Address of Certifying Organization(Mandatory)This is the name and address of the organizationthat accepts responsibil
20、ity for the information on the certificate.Organizations that provided analytical data or prepared thematerial may be provided elsewhere on the certificate.6.1.2 Material Identification (Mandatory)This sectionmust identify the material by name, as labeled, and mustinclude a lot or batch number that
21、can be used to uniquelyidentify the material.6.1.3 Supplier of the Reference Material (Optional)If thesupplier of the reference material is different from the certify-ing organization then this section should contain the name andaddress of the supplier of the material.6.1.4 Preparer of the Material
22、(Optional)If the materialwas not prepared by the supplier or the certifying organization,then this section should include the name and address of thepreparer of the material.6.1.5 Source of the Material (Mandatory)For a solutionstandard, or a matrix material, this section must identify thesource of
23、the raw materials or the source of the matrix material,used in the preparation of the material. The supplier mayidentify the source of the material as proprietary. If the sourceof the material is declared to be proprietary then the suppliermust provide contact information on the certificate in order
24、 toassist end users.6.1.6 Description and Intended Use of the Material(Optional)Most reference materials are designed to be usedfor a specific purpose. This section should designate theintended use of the material. It should also contain a suffi-ciently detailed description of the material to allow
25、the user toestimate its usability in their application.This material is designed to be used in D XXXX as a cali-bration standard. The material was prepared in Type Iwater to contain 1 mg/ml of the certified components.6.1.7 Stability, Transportation, and Storage Conditions(Mandatory)Any known temper
26、ature, storage, or transporta-tion factors that could influence the stability of the materialmust be identified. It is required that the supplier identifyproper storage and handling conditions that are necessary toinsure usability for the expected life of the material. Similarly,the supplier should
27、identify the period of time for which theywill assume responsibility for the validity of the certifiedvalues.6.1.8 Instructions for Use (Mandatory)If the materialrequires special handling, dilution, drying, or any other specificmanipulation in order to achieve the certified values, theseprocedures m
28、ust be clearly identified in this section.6.1.9 Method of Preparation (Optional)If the method ofpreparation gives the user an idea of the care taken by thesupplier, significant details of the preparation procedure maybe included in this section.6.1.10 State of Homogeneity (Mandatory)As it relates to
29、the certification of reference materials, homogeneity refers tothe analysis and demonstration of uniformity of final packagedunits. Every certificate must contain a homogeneity statement.This section must include the sampling, analytical method(s),and procedure used to evaluate the homogeneity of th
30、ematerial. Appendix X2 provides a suggested procedure forhomogeneity testing and references to alternative internation-ally accepted homogeneity testing procedures. If the homoge-neity of the material has not been determined, then this must bestated on the certificate.6.1.11 Certified Property Value
31、s and Their Associated Un-certainties (Mandatory)The information in this sectionshould be given in tabular form with appropriate subsectionheadings. The minimum information to be provided includesthe property, the certified value of the property, the associateduncertainty, and the method of analysis
32、. Since the certificate isa synopsis of the certification report, suppliers are encouragedto identify the method of analysis by appropriate standardmethod number. Modifications or exceptions to the givenmethod may be annotated in another section of the certificate.Likewise, if the values certified a
33、re dependent upon certainconditions, for example temperature, these can be identified infootnotes to the table. Values for properties that are not certifiedshould be included in a separate table.NOTE 1Several different procedures can be used to certify referencematerials. These depend upon the natur
34、e of the material to be certified andthe technical capability of the supplier and certifying body. The three mostcommon procedures for certification are detailed in Section 7. Theprocedure used to certify property values must be provided under theheading of statistical estimators and uncertainty ref
35、erenced below.6.1.12 Uncertified Properties (Optional)Many timesproperties of the material are known but without sufficientaccuracy or precision to support certification. These valuesmay be reported by the supplier in this section to assist the userin the selection of appropriate materials.6.1.13 Va
36、lues Obtained by Individual Laboratories or Meth-ods (Optional)Many times materials are certified based uponD 6362 98 (2008)2interlaboratory studies or by using several different methods ofanalysis. In these cases, this section can be used to reportindividual data by laboratory or method where appro
37、priate. Ifthe supporting data are too voluminous to report in this section,a reference to the certification report may be made here toidentify the source and availability of supporting data.6.1.14 Statistical Estimator and Uncertainty (Mandatory)The meaning and nature of the certified values must be
38、 given,that is, the statistical estimator must be named. Where theestimator cannot be named then the mathematical expressionused in calculation must be presented.The certified values are based upon the unweightedmean of nine independent measurements by eachmethod reported.The certified values are ba
39、sed upon a biweight estimateof the mean of the center 50 % of the reported data us-ing the Tukey Bisquare Procedure with a tuning constantof 3.97. Details of the procedure may be obtained fromthe certifier.NOTE 2The method used to estimate the uncertainty associated withthe certified value of the pr
40、operty is important. Therefore, the suppliermust identify the factors considered in estimation of uncertainty and themethod used for calculation. If the uncertainty is estimated by a coveragefactor, such as 2s/=n , then the formula and the values for each variablein the formula must be provided on t
41、he certificate.6.1.15 Measurement Methods Used for Certification(Optional)This section should provide the exceptions to, ormodifications of, the standard or reported method(s) used forcertification. Sufficient details of the analysis must be providedin the certification report to allow independent v
42、erification ofthe analytical values. However, only those details which areessential to reproducibility need to be reported.6.1.16 Identification of Analysts or Laboratories(Optional)This section may be used to identify the contri-bution of individual analysts or laboratories to the certificationeffo
43、rt. The identification of analysts or laboratories may assistthe user in establishing the quality of the certification data.6.1.17 Legal Notice (Optional)Disclaimers or legal limi-tations of liability for the information on the certificate shouldappear in this section.6.1.18 Reference to Certificati
44、on Report (Mandatory)Thecertification report supporting the summary provided on thecertificate must be unambiguously identified in this section.Instructions for obtaining the full certification report must beprovided in this section.6.1.19 Signature of Certifying Offcer (Mandatory)It isrequired that
45、 the officer of the certifying body who acceptsresponsibility for the information on the certificate sign thecertificate.6.1.20 Annex (Optional)The annex may be used by thesupplier to supply additional information about the material orits certification. It may contain graphical presentations or othe
46、rinformation not appropriate in the body of the certificate.7. Certification Procedures7.1 The certification procedure is the protocol used todevelop certification data. It is independent of the method(s)used for certification and is usually dependent upon the natureof the material to be certified.
47、The procedure used to certify thereference material is usually dependent upon the nature of thematerial and the property to be certified. In the case of a pureor neat compound to be used for preparation of calibrationmaterials, the properties of interest are confirmation of identityand an accurate a
48、ssay of the material. In the case of a preparedcalibration solution, the property of interest is the best estimateof the concentration of the analyte in the solvent. In the case ofa quality control material, the property of interest is theperformance of the material in a particular method.7.1.1 Most
49、 reference materials, and properties of interest,are certified by one of the following three procedures: 1) directcomparison method, most frequently used for assay work, oranalysis of calibration materials where a suitable NIST stan-dard reference material (SRM) exists; 2) verification of theprepared value, used to certify the prepared value of a materialif an SRM is not available for direct comparison; and, 3)interlaboratory certification procedure, used to establish typicalmethod performance values or an assigned value for matrixmaterials.7.1.2 In the ca
