1、AMERICAN NATIONAL STANDARDOCTOBER 2013ANSI/ASQ Z1.42003 (R2013)SAMPLING PROCEDURES AND TABLES FOR INSPECTION BY ATTRIBUTESThis standard is a reaffirmation of ANSI/ASQ Z1.42003 (R2008)AMERICANNATIONALSTANDARDSampling Procedures and Tables forInspectionby AttributesPreparedbyTheStatisticsSubcommitteeo
2、ftheAccreditedStandardsCommitteeZ1onQuality,Environment,DependabilityandStatisticsANSI-AccreditedStandardsDeveloper(ASD)AmericanSocietyforQualityABSTRACTSamplingProceduresandTablesforInspectionbyAttributesisanacceptancesamplingsystemtobeusedwithswitchingrulesonacontinuingstreamoflotsforAQLspecified.
3、Itprovidestightened,normal,andreducedplanstobeappliedforattributesinspectionforpercentnonconformingornonconformitiesper100units.AMERICAN NATIONAL STANDARD:AnAmericanNationalStandardimpliesaconsensusofthosesubstantiallycon-cerned with its scope and provisions.AnAmerican National Standard is intended
4、as a guide to aid the manufacturer, theconsumer,andthegeneralpublic.TheexistenceofanAmericanNationalStandarddoesnotinanyrespectprecludeany-one,whetherhehasapprovedthestandardornot,frommanufacturing,marketing,purchasing,orusingproducts,process-es,orproceduresnotconformingtothestandard.AmericanNationa
5、lStandardsaresubjecttoperiodicreviewandusersarecautionedtoobtainthelatestedition.CAUTION NOTICE:ThisAmerican National Standardmaybe revised orwithdrawnatany time.TheproceduresoftheAmerican National Standards Institute require that action be taken to reaffirm, revise, or withdraw this standard no lat
6、erthanfiveyearsfromthedateofpublication.PurchasersofAmericanNationalStandardsmayreceivecurrentinformationonallstandardsbycallingorwritingtheAmericanNationalStandardsInstitute.ANSI/ASQZ1.4-2003(R2013)00.Z1.4.fm(i-vi).qxd:00.Z1.4.fm(i-vi).qxd 10/9/13 10:01 AM Page i2013byASQCopyright protection notice
7、 forthe ANSI/ASQ Z1.4-2003 (R2013) Standard.ThisStandardissubjecttocopyrightclaimsofANSI,andASQ.Notforresale.Nopartofthispublicationmaybereproducedinanyform,includinganelectronicretrievalsystem,withoutthepriorwrittenpermissionofASQ.AllrequestspertainingtotheANSI/ASQZ1.4-2003(R2013)Standardshouldbesu
8、bmittedtoASQ.ASQwillconsiderrequestsforchangeandinformationonthesubmittalofsuchrequestsregardingthisStandard.AllrequestsshouldbeinwritingtotheattentionoftheStandardsAdministratorattheaddressbelow.ASQ Mission:TheAmericanSocietyforQualityadvancesindividualandorganizationalperformanceexcellenceworldwid
9、ebyprovidingopportunitiesforlearning,qualityimprovement,andknowledgeexchange.Publishedby:00.Z1.4.fm(i-vi).qxd:00.Z1.4.fm(i-vi).qxd 10/9/13 10:01 AM Page iiForewordiiiANSI/ASQZ1.4-2003(R2013)isaveryminorrevisionofANSI/ASQZ1.4-2003(R2008),“Sampling Procedures and Tables forInspection by Attributes”,al
10、soreferredtoasANSI/ASQZ1.4-2008.Changes:TableIIIADoubleSamplingPlansforNormalInspection(Mastertable)InthetitleAcceptanceQualityLimit,changedtheword“reduced”to“normal”inspection.TableVIIILimitNumbersforReducedInspectionIncolumn4.0for1250-1999,changedAcceptanceQualityLimitsfrom49to40.TableX-D-1Tabulat
11、edValuesforOperatingCharacteristicCurvesforSingleSamplingPlansIncolumn1.5for95.0,changed0639to0.639TableX-H-1TabulatedValuesforOperatingCharacteristicCurvesforSingleSamplingPlansIncolumn1.0for50.0,changed33.3to3.33TableX-N-2SamplingPlansforSampleSizeCodesIncolumn0.040,changedUseCodeLetterfromNtoMInt
12、hefirstXcolumn,changedUseCodeLetterfromRtoQIncolumn0.065,changedUseCodeLetterfromQtoPSuggestionsforimprovementofthisstandardarewelcomed.Sendyourcommentstothesponsor,ASQStandards,600NorthPlankintonAvenue,Milwaukee,WI53203orstandardsasq.org.00.Z1.4.fm(i-vi).qxd:00.Z1.4.fm(i-vi).qxd 10/9/13 10:01 AM Pa
13、ge iii(This page intentionally left blank)00.Z1.4.fm(i-vi).qxd:00.Z1.4.fm(i-vi).qxd 10/9/13 10:01 AM Page ivTable of ContentsParagraph Page1. SCOPE12. DEFINITIONSANDTERMINOLOGY .13. PERCENTNONCONFORMINGANDNONCONFORMITIESPERHUNDREDUNITS24. ACCEPTANCEQUALITYLIMIT(AQL)25. SUBMISSIONOFPRODUCT.36. ACCEPT
14、ANCEANDNON-ACCEPTANCE37. DRAWINGOFSAMPLES48. NORMAL,TIGHTENED,ANDREDUCEDINSPECTION .49. SAMPLINGPLANS.510. DETERMINATIONOFACCEPTABILITY 611. SUPPLEMENTARYINFORMATION 6TablesTableI SampleSizeCodeLetters 10TableII-A SingleSamplingPlansforNormalInspection(MasterTable) 11TableII-B SingleSamplingPlansfor
15、TightenedInspection(MasterTable) 12TableII-C SingleSamplingPlansforReducedInspection(MasterTable) .13TableIII-A DoublingSamplingPlansforNormalInspection(MasterTable)14TableIII-B DoublingSamplingPlansforTightenedInspection(MasterTable)15TableIII-C DoublingSamplingPlansforReducedInspection(MasterTable
16、).16TableIV-A MultipleSamplingPlansforNormalInspection(MasterTable).17TableIV-B MultipleSamplingPlansforTightenedInspection(MasterTable) 19TableIV-C MultipleSamplingPlansforReducedInspection(MasterTable)21TableV-A FactorsforDeterminingApproximateValuesforAverageOutgoingQualityLimitsforNormalInspecti
17、on(SingleSampling)23TableV-B FactorsforDeterminingApproximateValuesforAverageOutgoingQualityLimitsforTightenedInspection(SingleSampling)24TableVI-A LimitingQuality(inpercentnonconforming)forWhichPa=10Percent(forNormalInspection,SingleSampling)25TableVI-B LimitingQuality(innonconformitiesperhundredun
18、its)forWhichPa=10Percent(forNormalInspection,SingleSampling)26TableVII-A LimitingQuality(inpercentnonconforming)forWhichPa=5Percent(forNormalInspection,SingleSampling)27TableVII-B LimitingQuality(innonconformitiesperhundredunits)forWhichPa=5Percent(forNormalInspection,SingleSampling)28TableVIII Limi
19、tNumbersforReducedInspection29TableIX AverageSampleSizeCurvesforDoubleandMultipleSamplingPlans(normalandtightenedinspection)30TableX-A SampleSizeCodeLetterAIndividualPlans 31TableX-B SampleSizeCodeLetterBIndividualPlans 33TableX-C SampleSizeCodeLetterCIndividualPlans 35ANSI/ASQZ1.4-2003(R2013)v00.Z1
20、.4.fm(i-vi).qxd:00.Z1.4.fm(i-vi).qxd 10/9/13 10:01 AM Page vviTableX-D SampleSizeCodeLetterDIndividualPlans 37TableX-E SampleSizeCodeLetterEIndividualPlans 39TableX-F SampleSizeCodeLetterFIndividualPlans 41TableX-G SampleSizeCodeLetterGIndividualPlans 43TableX-H SampleSizeCodeLetterHIndividualPlans
21、45TableX-J SampleSizeCodeLetterJIndividualPlans.47TableX-K SampleSizeCodeLetterKIndividualPlans 49TableX-L SampleSizeCodeLetterLIndividualPlans 51TableX-M SampleSizeCodeLetterMIndividualPlans53TableX-N SampleSizeCodeLetterNIndividualPlans 55TableX-P SampleSizeCodeLetterPIndividualPlans 57TableX-Q Sa
22、mpleSizeCodeLetterQIndividualPlans 59TableX-R SampleSizeCodeLetterRIndividualPlans 61TableX-S SampleSizeCodeLetterSIndividualPlans 63TableXI AverageOutgoingQualityLimitFactorsforANSI/ASQ-Z1.4SchemePerformance(SingleSampling).64TableXII LimitingQualityforANSI/ASQ-Z1.4SchemePerformanceforWhichPa=10Per
23、cent(SingleSampling)65TableXIII LimitingQualityforANSI/ASQ-Z1.4SchemePerformanceforWhichPa=5Percent(SingleSampling).66TableXIV AverageSampleSizeTablesforANSI/ASQ-Z1.4SchemePerformance(SingleSampling).67TableXV-A SampleSizeCodeLetterASchemePerformance 71TableXV-B SampleSizeCodeLetterBSchemePerformanc
24、e 72TableXV-C SampleSizeCodeLetterCSchemePerformance 73TableXV-D SampleSizeCodeLetterDSchemePerformance 74TableXV-E SampleSizeCodeLetterESchemePerformance 75TableXV-F SampleSizeCodeLetterFSchemePerformance.76TableXV-G SampleSizeCodeLetterGSchemePerformance 77TableXV-H SampleSizeCodeLetterHSchemePerf
25、ormance 78TableXV-J SampleSizeCodeLetterJSchemePerformance.79TableXV-K SampleSizeCodeLetterKSchemePerformance 80TableXV-L SampleSizeCodeLetterLSchemePerformance 81TableXV-M SampleSizeCodeLetterMSchemePerformance82TableXV-N SampleSizeCodeLetterNSchemePerformance 83TableXV-P SampleSizeCodeLetterPSchem
26、ePerformance.84TableXV-Q SampleSizeCodeLetterQSchemePerformance 85TableXV-R SampleSizeCodeLetterRSchemePerformance 86INDEXOFTERMSWITHSPECIALMEANINGS.87ANSI/ASQZ1.4-2003(R2013)00.Z1.4.fm(i-vi).qxd:00.Z1.4.fm(i-vi).qxd 10/9/13 10:01 AM Page vi1. SCOPE1.1 PURPOSE. This publication establishes samplingp
27、lans and procedures for inspection by attributes. Whenspecifiedbytheresponsibleauthority,thispublicationshallbe referenced in the specification, contract, inspectioninstructions,orotherdocumentsandtheprovisionssetforthherein shall govern. The “responsible authority” shall bedesignatedinoneoftheabove
28、documents,asagreedtobythepurchaserandsellerorproduceranduser.1.2 APPLICATION. Sampling plans designated in thispublicationareapplicable,butnotlimited,toinspectionofthefollowing:a. Enditems.b. Componentsandrawmaterials.c. Operations.d. Materialsinprocess.e. Suppliesinstorage.f. Maintenanceoperations.
29、g. Dataorrecords.h. Administrativeprocedures.Theseplansareintendedprimarilytobeusedforacontinu-ingseriesoflotsorbatches.Theplansmayalsobeusedfortheinspectionofisolatedlotsorbatches,but,inthislattercase,theuseriscautionedtoconsulttheoperatingcharac-teristiccurvestofindaplanwhichwillyieldthedesiredpro
30、-tection(see11.6).1.3 INSPECTION.Inspection is the process of measur-ing,examining,testing,orotherwisecomparingtheunitofproduct(see1.5)withtherequirements.1.4 INSPECTION BY ATTRIBUTES. Inspection byattributesisinspectionwherebyeithertheunitofproductis classified simply as conforming or nonconforming
31、, orthe number of nonconformities in the unit of products iscounted, with respect to a given requirement or set ofrequirements.1.5 UNITOFPRODUCT.Theunitofproductistheunitinspected in order to determine its classification as con-formingornonconformingortocountthenumberofnon-conformities.Itmaybeasingl
32、earticle,apair,aset,alength,an area, an operation, a volume, a component of an endproduct,ortheendproductitself.Theunitofproductmayormaynotbethesameastheunitofpurchase,supply,pro-duction,orshipment.2. DEFINITIONSANDTERMINOLOGYThedefinitionsandterminologyemployedinthisstandardareinaccordwithISO3534-2
33、(Terms,Symbols,andDefinitionsforAcceptanceSampling).Thefollowingtwodefinitionsareparticularlyimportantinapplyingthestandard.DEFECT:Adepartureofaqualitycharacteristicfromitsintendedlevelorstatethatoccurswithaseveritysufficienttocauseanassociatedproductorservicenot to satisfy intended normal, or fores
34、eeable,usagerequirements.NONCONFORMITY:Adepartureofaqualitycharac-teristicfromitsintendedlevelorstatethatoccurswithseveritysufficienttocauseanassociatedprod-uctorservicenottomeetaspecificationrequire-ment.Theseacceptancesamplingplansforattributesaregivenintermsofthepercentorproportionofproductinalot
35、orbatchthat depart from some requirement. The general terminol-ogyusedwithinthedocumentwillbegivenintermsofper-centofnonconformingunitsornumberofnonconformities,since these terms are likely to constitute the most widelyusedcriteriaforacceptancesampling.In the use of this standard it is helpful to di
36、stinguishbetween:a. an individual sampling plana specific plan thatstatesthesamplesizeorsizestobeused,andtheassociatedacceptancecriteria.1SAMPLINGPROCEDURESANDTABLESFORINSPECTIONBYATTRIBUTES01.Z1.4(001-088).qxd:01.Z1.4(001-088).qxd 10/8/13 9:45 AM Page 1b. a sampling schemea combination of samplingp
37、lanswithswitchingrulesandpossiblyaprovisionfor discontinuance of inspection. In this standardthe terms “sampling scheme” and “scheme per-formance” will be used in the restricted sensedescribedinSec.11.1.c. a sampling systema collection of samplingschemes.Thisstandardisasamplingsystemindexedbylot-siz
38、eranges,inspectionlevels,andAQLs.3. PERCENTNONCONFORMINGANDNONCONFORMITIESPERHUNDREDUNITS3.1 EXPRESSION OF NONCONFORMANCE. Theextent of nonconformance of product shall be expressedeitherintermsofpercentnonconformingorintermsofnon-conformitiesperhundredunits.3.2 PERCENTNONCONFORMING.Thepercentnon-con
39、formingofanygivenquantityofunitsofproductisonehundredtimesthenumberofnonconformingunitsdividedbythetotalnumberofunitsofproduct,i.e.:3.3 NONCONFORMITIESPERHUNDREDUNITS.The number of nonconformities per hundred units of anygivenquantityofunitsofproductisonehundredtimesthenumberofnonconformitiescontain
40、edtherein(oneormorenonconformities being possible in any unit of product)dividedbythetotalnumberofunitsofproduct,i.e.:Itisassumedthatnonconformitiesoccurrandomlyandwithstatisticalindependencewithinandbetweenunits.4. ACCEPTANCEQUALITYLIMIT(AQL)4.1 USE. The AQL together with the Sample Size CodeLetter
41、,isusedforindexingthesamplingplansprovidedherein.4.2 DEFINITION.TheAQListhequalitylevelthatistheworsttolerableprocessaveragewhenacontinuingseriesoflotsissubmittedforacceptancesampling.Note:TheuseoftheabbreviationAQLtomeanAcceptableQualityLevelisnolongerrecommended.4.3 NOTEONTHEMEANINGOFAQL.Theconcep
42、tofAQLonlyapplieswhenanacceptancesamplingschemewith rules for switching between normal, tightened andreducedinspectionanddiscontinuanceofsamplinginspec-tionisused.TheserulesaredesignedtoencouragesupplierstohaveprocessaveragesconsistentlybetterthantheAQL.Ifsuppliersfailtodoso,thereisahighprobabilityo
43、fbeingswitched from normal inspection to tightened inspectionwherelotacceptancebecomesmoredifficult.Onceontight-enedinspection,unlesscorrectiveactionistakentoimproveproductquality,itisverylikelythattherulerequiringdis-continuanceofsamplinginspectionwillbeinvoked.Althoughindividuallotswithqualityasba
44、dastheAQLcanbeacceptedwithfairlyhighprobability,thedesignationofanAQL does not suggest that this is necessarily a desirablequality level. The AQL is a parameter of the samplingschemeandshouldnotbeconfusedwithaprocessaveragewhich describes the operating level of a manufacturingprocess.Itisexpectedtha
45、ttheproductqualitylevelwillbelessthantheAQLtoavoidexcessivenon-acceptedlots.ThesamplingplansinthisstandardaresoarrangedthattheprobabilityoflotacceptanceatthedesignatedAQLdependsuponsamplesize,beinggenerallyhigherforlargesamplesthanforsmallsamplesforagivenAQL.Todeterminethespecificprotectiontothecons
46、umeratagivenAQL,itisnec-essarytorefertotheoperatingcharacteristiccurves(whichareprovidedinthisstandard)ofthecorrespondingschemeanditsconstituentplans.TheAQLalonedoesnotdescribetheprotectiontothecon-sumerforindividuallotsorbatches,butmoredirectlyrelatestowhatisexpectedfromaseriesoflotsorbatchesprovid
47、edtheprovisionsofthisstandardaresatisfied.4.4 LIMITATION.ThedesignationofanAQLshallnotimply that the supplier has the right to knowingly supplyanynonconformingunitofproduct.4.5 SPECIFYINGAQLs.The AQL to be used will bedesignated in the contract or by the responsible authority.DifferentAQLsmaybedesig
48、natedforgroupsofnonconfor-mitiesconsideredcollectively,orforindividualnonconfor-mities.Forexample,GroupAmayincludenonconformitiesofatypefelttobeofthehighestconcernfortheproductorserviceandthereforebeassignedasmallAQLvalue;GroupBmayincludenonconformitiesofthenexthigherdegreeofconcernandthereforebeass
49、ignedalargerAQLvaluethanforGroupAandsmallerthanthatofGroupC,etc.Theclas-sification into groups should be appropriate to the qualityNonconformitiesper=Numberofnonconformities100hundredunits NumberofunitsinspectedNumbernonconformingPercentnonconforming=Numberofunitsinspected100ANSI/ASQZ1.4-2003(R2013)201.Z1.4(001-088).qxd:01.Z1.4(001-088).qxd 10/8/13 9:45 AM Page 2requirementsofthespecificsituation.AnAQLforagroupofnonconformitiesmaybedesignatedinadditiontoAQLsfor individual nonconformities, or subgroups, within thatgroup.AQLvaluesof10.0orless
