ASTM_E_2867_-_14.pdf

Designation:E286714Standard Practice forEstimating Uncertainty of Test Results Derived fromSpectrophotometry1This standard is issued under the fixed designation E2867;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 describes a protocol to be utilized bymeasurement laboratories for estimating and reporting theuncertainty of a measurement result when the result is derivedfrom a measurand that has been obtained by spectrophotom-etry.1.2 This practice is specifically limited to the reporting ofuncertainty of color measurement results that are reported ascolor-differences in E format,even though the measurementitself may be reported in other units such as percent reflectanceor transmittance.1.3 The procedures defined here are not intended to beapplicable to national standardizing laboratories or transferlaboratories.1.4 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:2D2244 Practice for Calculation of Color Tolerances andColor Differences from Instrumentally Measured ColorCoordinatesE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE284 Terminology of Appearance2.2 ISO Standards:3ISO 9001 Quality Management SystemsRequirementsISO/IEC 17025 General Requirements for the Competenceof Calibration and Testing Laboratories2.3 Other Standard:4QS9000 QualitySystemsRequirementsChryslerCorporation,Ford Motor Company,General Motors Cor-poration3.Terminology3.1 Definitions:For definitions of terms used in this stan-dard refer to Terminology E284.3.2 Definitions of Terms Specific to This Standard:3.2.1 uncertainty,na parameter associated with a mea-surement result or test result that reasonably characterizes thedispersion of results attributable to the particular quantity beingmeasured of the particular characteristic being tested.3.2.2 instrumentuncertaintyconditions,nofameasurement,conditions wherein the measurements are maderepetitively and carefully over a short timescale,withoutreplacement of the specimen being measured in the specimenport of the instrument.NOTE1Instrument uncertainty conditions always include potentialspecimen drift due to causes such as theromchromism,photochromism,orbleaching of the specimen.While these may be thought of as character-istics of the specimen,their effects will be picked up here under instrumentuncertainty conditions.3.2.3 operatoruncertaintyconditions,nofameasurement,conditions wherein the measurements are maderepetitively and carefully over a short timescale,with replace-ment of the specimen being measured by the operator com-pletely withdrawing the specimen from the specimen port andreplacing the specimen back in the specimen port prior to theensuing measurement so that the specimen aperture samplesthe same location on the specimen,and the specimen has thesame orientation as previous,to the best of the operatorsability to accomplish.3.2.4 uniformityuncertaintyconditions,nofameasurement,conditions wherein the measurements are maderepetitively and carefully over a short timescale,with replace-ment of the specimen being measured to an entirely new1This practice is under the jurisdiction of ASTM Committee E12 on Color andAppearance and is the direct responsibility of Subcommittee E12.04 on Color andAppearance Analysis.Current edition approved May 1,2014.Published May 2014.Originallyapproved in 2013.Last previous edition approved in 2013 as E2867 13.DOI:10.1520/E2867-14.2For 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,http:/www.ansi.org.4Available from Automotive Industry Action Group(AIAG),26200 Lahser Rd.,Suite 200,Southfield,MI 48033,http:/www.aiag.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 location on the face of the specimen with the intent of samplingthe entire surface of the specimen,or as much of the surface asis practical,by the end of the repetitive sampling run.3.2.5 instrument uncertainty,nthe results of an uncer-tainty analysis of a measurement system made under instru-ment uncertainty conditions.3.2.6 operator uncertainty,nthe results of an uncertaintyanalysis of a measurement system made under operator uncer-tainty conditions.3.2.7 uniformity un