【英文标准名称】:Samplingproceduresforinspectionbyvariables-Guidetodoublesamplingschemesindexedbyacceptancequalitylimit(AQL)forlot-by-lotinspection
【原文标准名称】:变量检验用取样程序.逐批检验用合格质量等级(AQL)标注的双取样方案指南
【标准号】:BS6002-3-2005
【标准状态】:现行
【国别】:英国
【发布日期】:2005-03-31
【实施或试行日期】:2005-03-31
【发布单位】:英国标准学会(GB-BSI)
【起草单位】:BSI
【标准类型】:()
【标准水平】:()
【中文主题词】:质量保证;检验;验收检验;抽样方法;计量检查;双;统计质量控制;抽样表;质量控制
【英文主题词】:Acceptanceinspection;Double;Inspection;Inspectionbyvariables;Qualityassurance;Qualitycontrol;Samplingmethods;Samplingtables;Statisticalqualitycontrol
【摘要】:ThisBritishStandardspecifiesanacceptancesamplingsystemofdoublesamplingschemesforinspectionbyvariablesforpercentnonconforming.Itisindexedintermsoftheacceptancequalitylimit(AQL).TheobjectivesofthemethodslaiddowninthisBritishStandardaretoensurethatlotsofacceptablequalityhaveahighprobabilityofacceptanceandthattheprobabilityofnon-acceptinginferiorlotsisashighaspracticable.Thisisachievedbymeansoftheswitchingrules,whichprovide:a)automaticprotectiontotheconsumer(bymeansofaswitchtotightenedinspectionordiscontinuationofsamplinginspection)shouldadeteriorationinqualitybedetected;b)anincentive(atthediscretionoftheresponsibleauthority)toreduceinspectioncosts(bymeansofaswitchtoasmallersamplesize)shouldconsistentlygoodqualitybeachieved.InthisBritishStandard,theacceptabilityofalotisimplicitlyorexplicitlydeterminedfromanestimateofthepercentageofnonconformingitemsintheprocess,basedoneitheroneortworandomsamplesofitemsfromthelot.ThisBritishStandardisprimarilydesignedforuseunderthefollowingconditions:a)wheretheinspectionprocedureistobeappliedtoacontinuingseriesoflotsofdiscreteproductsallsuppliedbyoneproducerusingoneproductionprocess.Iftherearedifferentproducersorproductionprocesses,thisBritishStandardshallbeappliedtoeachoneseparately;b)wheretheitemsofproducthaveasinglequalitycharacteristic(formultiplequalitycharacteristics,seeAnnexA,AnnexBandAnnexC,whichareallinformative);c)wherethequalitycharacteristicismeasurableonacontinuousscale;d)wherethemeasurementerrorisnegligible(i.e.withastandarddeviationnomorethan10%ofthecorrespondingprocessstandarddeviation);e)whereproductionisstable(understatisticalcontrol)andthequalitycharacteristicisdistributed,atleasttoacloseapproximation,accordingtoanormaldistribution;CAUTION.TheproceduresinthisBritishStandardarenotsuitableforapplicationtolotsthathavebeenscreenedpreviouslyfornonconformingitems.f)wherethepossibilityofhavingtoselectandinspectasecondsampleisadministrativelyacceptable;g)whereacontractorstandarddefinesanupperspecificationlimitU,alowerspecificationlimitL,orbothonthequalitycharacteristic.Anitemisdeemedtoconformifitsmeasuredqualitycharacteristicxsatisfiestheappropriateoneofthefollowinginequalities:i)x≤U(i.e.theupperspecificationlimitisnotviolated);ii)x≥L(i.e.thelowerspecificationlimitisnotviolated);iii)x≤Uandx≥L(i.e.neithertheuppernorthelowerspecificationlimitisviolated).NOTEInequalitiesi)andii)arecalledcaseswitha"singlespecificationlimit",andiii)isthecasewith"doublespecificationlimits".Fordoublespecificationlimits,afurtherdistinctionismadebetweencombinedcontrol,separatecontrolandcomplexcontrol,asfollows:—combinedcontroliswhereasingleAQLappliestononconformitybeyondbothlimits;—separatecontroliswhereseparateAQLsapplytononconformitybeyondeachofthelimits;—complexcontroliswhereoneAQLappliestononconformitybeyondthelimitthatisofgreaterseriousness,andalargerAQLappliestothetotalnonconformitybeyondbothlimits.
【中国标准分类号】:A41
【国际标准分类号】:03_120_30
【页数】:110P.;A4
【正文语种】:英语