儀器確認(rèn)-附件8-天平確認(rèn)-中英文

ANNEX8OFTHEOMCLNETWORKGUIDELINE

“QUALIFICATIONOFEQUIPMENT”儀器確認(rèn)QUALIFICATIONOFBALANCES天平的確認(rèn)1.INTRODUCTION介紹Thisdocumentisthe8thAnnextothecoredocument“QualificationofEquipment”,whichtogethershouldbeusedwhenplanning,performinganddocumentingthequalificationprocessofbalances.本文件是核心文件“儀器的確認(rèn)”第8個附件，在計劃、實施和記錄天平的確認(rèn)過程時，應(yīng)將本文件與核心文件一起使用。ThecoredocumentcontainstheintroductionandgeneralformsforLevelIandIIofqualification,whicharecommontoalltypesofinstruments.核心文件包括了第一級和第二級確認(rèn)的介紹和通用表格，適用于所有類型的儀器。Annex8containsinstrument-relatedrecommendationsonparameterstobecheckedatLevelIIIandIVofqualificationandthecorrespondingtypicalacceptancelimits,aswellaspracticalexamplesonthemethodologythatcanbeusedtocarryoutthesechecks.附件8包括了儀器相關(guān)的的推薦：在第三級和第四級確認(rèn)中需要檢查的參數(shù)和對應(yīng)的典型的可接受標(biāo)準(zhǔn)，以及可用于進(jìn)行這些檢查的實用方法學(xué)舉例。AIMANDSCOPEOFTHEGUIDELINE目的和范圍Thisguidelinedescribestherequirementsforbalances(electronic-digital)usedinchemicalandbiologicaltestsinOMCLs.本指南描述了用于OMCLs化學(xué)和生物測試所用天平的要求(電子-數(shù)字)。Thefollowingtypesofbalancesareconsideredinthisguideline(Table1):本指南中涉及的天平類型包括(表1)：Table1

Type類型Ordinaryname名稱Numberofdigitsafterdecimalposition(g)天平分度值A(chǔ)ccuracyClass準(zhǔn)確度等級1.UltraMicroBalances超微量天平7I2.MicroBalances微量天平6I3.Semi-microBalances半微量天平5I4.AnalyticalBalances分析天平4I5.PrecisionBalances精密天平1to3II6.TechnicalBalances技術(shù)天平0to1mTheclassificationsarebasedontheOIMLR76-1InternationalRecommendationdocument(seeTable2).該分類基于OIMLR76-1國際推薦的文件(見表2)Table2:Theverificationscaleinterval,numberofverificationscaleintervalsandminimumcapacityinrelationtotheaccuracyclassofaninstrument.表2：檢定分度值，檢定分度數(shù)和與儀器準(zhǔn)確度級別相關(guān)的最小稱量Accuracyclass準(zhǔn)確度級Verificationscaleinterval(e)檢定分度值(e)Numberofverificationscaleintervals(n=Max/e)檢定分度數(shù)MinimumCapacity(Min)

別Minimum最小Maximum最大(Lowerlimit)最小稱量SpecialI特種0.001g<e(Itisnotnormallyfeasibletotestandverifyaninstrumenttoe<1Itisnotnormallyfeasibletotestandverifyaninstrumenttoe<1mgduetotheuncertaintyofthetestloads.由于測量負(fù)荷的不確定度，測試和確認(rèn)e<1mg的儀器通常是不可行的。50000(ForaninstrumentofclassIwithd<0.1mg,nForaninstrumentofclassIwithd<0.1mg,nmaybelessthan50000.Theminimumcapacityisreducedto5eforgradinginstruments,i.e.instrumentsthatdetermineatransporttariffortoll(eg.postalscalesandinstrumentsweighingwastematerial).對于具有d<0.1mg的一級儀器，n可能小于50000,對于儀器的定級最小稱量值減小到5e，即用于確定運(yùn)輸關(guān)稅或過路費(fèi)(例如：郵政磅秤和稱量廢料的儀器)。Onmultiplerangeinstruments,theverificationscaleintervalsaree1,e2,…，erwithe1<e2<…<er.Similarsub-scriptsarealsousedwiththetermsMin,nandMax.多量程儀器，檢定分度值分別用e1,e2,…，er表示，其中e1<e2<…<er。術(shù)語Min,n和Max也使用類似的腳標(biāo)。Onmultiplerangeinstruments,eachrangeistreatedasifitwereaninstrumentwithonerange.多量程儀器，每個量程均應(yīng)按照單量程儀器處理。Forspecialapplicationsthatareclearlymarkedontheinstrument,aninstrumentmayhaveweighingrangesinclassesIandII,orinclassesIIandIII.Theinstrumentasawholeshallthencomplywiththemoresevererequirementsof3.9Variationsdueto100eHigh0.001g<e<0.05g10010000020eII高0.1g<e500010000050eMedium0.1g<e<2g1001000020em中5g<e5001000020eOrdinarym普通5g<e100100010e

influencequantitiesandtimeapplicabletoeitherofthetwoclasses(seeOIMLR76-1InternationalRecommendationdocument)對于儀器上清楚標(biāo)識的特殊用途，儀器可能有一級和二級或者三級和四級的稱量范圍。將儀器作為一個整體并符合更嚴(yán)格的要求，“3.9由于影響量和時間引起的變化”(參見OIMLR76-1國際推薦文件)適用于兩種情況。Max=Maximumcapacityofthebalance天平的最大量程e=verificationscaleinterval檢定分度值e1,ei,er=verificationscaleinterval,rulesforindices檢定分度值，索弓1規(guī)定CONSIDERATIONSFORLEVELIANDIIOFEQUIPMENTQUALIFICATION一級和二級設(shè)備確認(rèn)的注意事項AtLevelIofthequalificationofbalances(selectionofinstrumentsandsuppliers),itisrecommendedtoselectamanufacturerofbalancesthatcansatisfytheneedsofthelaboratoryandworksunderISO9001certification.天平的一級確認(rèn)(儀器和供應(yīng)商選擇)，推薦選擇能夠滿足實驗室需要和通過ISO9001認(rèn)證的天平生產(chǎn)商。AtLevelIIofthequalificationofbalances(installationandreleaseforuse),itisrecommendedtocheckalltherequirementssetduringtheselectionoftheinstrumentandcalibrationshouldbeperformedbeforeputtingintoservicebyanaccreditedexternalservicesupplier,orinternallybyappropriatelyqualifiedpersonnel,usingcertifiedreferenceweightsaccordingtoanapprovedprocedure.天平的二級確認(rèn)(安裝和放行使用)，推薦檢查在選擇儀器時設(shè)定的所有要求，在投入使用前應(yīng)由官方認(rèn)可的外部服務(wù)提供商進(jìn)行校準(zhǔn)，或者由內(nèi)部具有合適資質(zhì)的人員使用標(biāo)準(zhǔn)砝碼按照批準(zhǔn)的程序進(jìn)行校準(zhǔn)。REQUIREMENTSFORBALANCEUSE天平使用的要求LocationoftheBalance位置Theaccuracyandprecisionofweighingresultsarecloselyassociatedwiththelocationofthebalance.OMCLsshouldensurethatthebalancecanworkunderoptimalconditions(weighingroom/laboratory,weighingbench,temperature,light,air,etc).

稱量結(jié)果的準(zhǔn)確度和精確度與天平的放置位置密切相關(guān)。OMCLs應(yīng)該確保天平始終工作在最佳狀態(tài)（稱量間/實驗室，稱量臺，溫度，光線，空氣等）。Itisrecommendedthatbalancesoftypes1to6(seeTable1above)arelocatedinaspeciallydesignedweighingroomthatisvibration-proof,dust-freeandhasananti-staticfloor.Forsubstancesthataresensibletostaticelectricityitisalsopossibletouseanionisingunit.類型1~6的天平(見上述表1)推薦放置在專門設(shè)計的防振動、無塵、擁有防靜電地板的稱量室中。對于易產(chǎn)生靜電的物質(zhì)也可以使用電離單元。Ifabalanceoftype1to6islocatedinalaboratoryoutsideoftheweighingroom,thentheweighingbenchonwhichitisplacedshouldbeinaseparatepartofthelaboratorythatisvibration-proofanddust-free.Forbalancesoftypes1to4,astablebenchshouldbeused.如果類型1~6的天平被置于稱量室外的實驗室中使用時，則應(yīng)將其放在位于實驗室中一個相對獨立區(qū)域的稱量臺上，防振動且無塵。對于類型1~4的天平應(yīng)該使用穩(wěn)定的稱量臺。Itshouldbeensuredthattheweighingbenchisstable,nomatterfromwhatmaterialitismade.Theweighingbenchshouldnotdeformwhenworkiscarriedoutonitanditmustbevibration-prooforthetransferofvibrationsmustnotinfluencetheweighingprocess.Ifthereisariskofinstability,thebalanceshouldbeequippedwithastabilityindicatorsothattheweightisonlyregisteredorprintedafterstabilisationofthebalance.無論用什么材質(zhì)，都必須保證稱量臺穩(wěn)固。在上面進(jìn)行稱量操作時，稱量臺不能變形，必須防振或者在轉(zhuǎn)移振動時絕不能影響稱量過程。如果存在不穩(wěn)定風(fēng)險，則天平必須裝備穩(wěn)定性指示器，只有天平處于穩(wěn)定狀態(tài)才能記錄或打印稱量值。Theweighingbenchshouldbenon-magnetic(i.e.nosteelplates)andprotectedagainstelectrostaticcharges(noplasticorglass).稱量臺應(yīng)該不具有磁性(即非鐵材料)且防靜電(非塑料或玻璃材質(zhì))。Temperature溫度Asweighingresultsareinfluencedbytemperature,OMCLsshouldensureaconstanttemperatureismaintainedinweighingrooms/laboratories.Thetypicaldriftofbalancesoftypes1and2is1-2ppm/°C.Thedeviationshouldnotexceedmorethan5°Cperhour.

稱量結(jié)果受到溫度影響時，OMCLs應(yīng)該確保稱量室/實驗室的溫度恒定。典型的溫度漂移值類型1和2的天平是：1~2ppm/°C。偏差每小時不得超過5°C。Atmospherichumidity空氣濕度Theoptimumrelativehumidity(%RH)duringaweighingprocessisbetween40%to60%forbalancesofclasslandII(seeTable1).Therelativehumiditymaybeexpandedto20%to80%incaseswheretheaccuracyandlinearityofmeasurementsarenotaffected.稱量過程第I級和第II級天平(見表1)的最佳相對濕度(％RH)是40%~60%。當(dāng)相對濕度范圍擴(kuò)展到20%~80%時，測量的準(zhǔn)確度和線性可以不受影響(小于20%RH或大于80%RH，請勿操作天平)。Light光照Balancesshouldbeprotectedfromdirectsunlight(heat).天平應(yīng)該避免陽光直射(溫度)。Air氣流OMCLsshouldnotplacebalancesintheairflowofairconditionersordeviceswithventilators(suchascomputersorlargelaboratoryequipment),nexttodoorwaysorinareasofhightraffic.Thisisbecauseinadditiontothepotentialtemperaturedrift,strongaircurrentscaninterferewiththefunctioningofbalances.Ifabalanceisplacedinalaminarflowworkstation,e.g.forweighingoftoxicmaterial,thecabinetshouldbesuitablefortheintendeduse.OMCLs不應(yīng)該將天平放置于空調(diào)或氣扇等風(fēng)源(電腦或大型實驗室裝置)產(chǎn)生的氣流中，靠近門或者人流多的地方。因為除了潛在的溫度漂移，強(qiáng)氣流可能干擾天平的運(yùn)行。如果將天平置于層流臺中，例如：有毒物料稱量，應(yīng)使用防風(fēng)罩以滿足要求。Weighingvessel稱量容器OMCLsmustensurethat:OMCLs必須確保thesmallestpossibleweighingvesselsareused.使用盡可能小的稱量容器。ifthematerialsthattheweighingvesselismadeofhaveahighdegreeofelectricalinsulation(suchasglassandplastic),theyarenotelectrostaticallycharged.

具有高度絕緣性的材料（如：玻璃與塑料）不應(yīng)帶有靜電電荷（注：高絕緣性材料本身不帶靜電，但不能釋放集聚的電荷）。theweighingvesselandthesampleitcontainsshouldhavethesametemperatureastheirsurroundings.稱量容器及樣品的溫度應(yīng)當(dāng)與環(huán)境溫度相同。iftheweighingvesselhasbeenremovedfromadryingovenordishwasher,itshouldbecooledtoroomtemperaturepriortobeingplacedonthebalance.從干燥箱或清洗機(jī)中取出的稱量容器，稱量前應(yīng)冷卻至室溫。dependingonthetypeofbalance,itisrecommendedtousecottongloves.推薦使用棉手套，這取決于天平類型。nomagnetsshouldbeplacedonthebalanceorintotheweighingvessel.天平或稱量容器中不能放置磁性物質(zhì)。REQUIREMENTSFORWEIGHTSUSEDINTHEQUALIFICATION確認(rèn)所用砝碼的要求Weightsusedforqualificationshould:用于確認(rèn)的砝碼：becleanand,ifnecessary,wipedwithethanol.Inthelattercaseawaitingtimemustbetakenintoaccountbeforetheweightisused應(yīng)干凈，必要時用乙醇擦拭。如用乙醇進(jìn)行過擦拭，則在稱量前必須考慮等待時間。bestoredinadust-freeenvironment.應(yīng)儲存在無塵環(huán)境中。behandledwithcare;theuseofcottonglovesorforceps/tweezersisespeciallyrecommended.應(yīng)該小心取用；推薦使用棉手套或鑷子/鉗子。haveasuitableaccuracy,dependingonthetypeofbalance.有合適的準(zhǔn)確度，這取決于所用的天平類型

becalibratedbyanaccreditedexternalserviceprovider.由官方認(rèn)可的外部服務(wù)提供商校準(zhǔn)合格。bere-calibratedperiodically.應(yīng)周期性再校準(zhǔn)。beclearlymarkedaftereachcalibration.每次校準(zhǔn)后應(yīng)清楚標(biāo)識notbemadeofmagnetisablematerial.不能用磁性材料制作theverification(inusecontrol,seeTable3)maybedonewithnon-calibratedweights.檢定(使用控制，見表3)可以使用未校準(zhǔn)砝碼FREQUENCYOFQUALIFICATION確認(rèn)頻次OMCLsmustensurethatqualification/calibrationofbalancesisdoneonreceipt(i.e.immediatelyafterdelivery)orpriortotheirfirstuseandafteranyrepairormove.OMCLs必須確保天平接收時進(jìn)行了確認(rèn)/校準(zhǔn)(即交貨后立即進(jìn)行)或者在第一次使用前和維修或移動后進(jìn)行。Thefrequencyofqualification/calibrationdependsontheextentofuseofthebalancesandisatthediscretionofindividualOMCLs.確認(rèn)/校準(zhǔn)頻次取決于天平使用程度和各OMCLs的決定。Qualification/calibrationmustbeperformedinaccordancewithapre-determinedprotocolinwhichacceptancecriteriaaredefined.AnexternalcalibrationshouldbeperformedbyorganisationsaccreditedascalibratinglaboratoriesaccordingtoISO/IEC17025or,ifperformedinternally,thelaboratoryshouldsatisfythesamerequirementsintermsofmeasurementstandards,calibrationprocedure,useofcertifiedweightsandqualificationofpersonnel.確認(rèn)/校準(zhǔn)必須按照預(yù)定方案執(zhí)行，方案中應(yīng)規(guī)定可接受標(biāo)準(zhǔn)。外部校準(zhǔn)應(yīng)由被認(rèn)可作為校準(zhǔn)實驗室的機(jī)構(gòu)根據(jù)ISO/IEC17025進(jìn)行；或者執(zhí)行內(nèi)部校準(zhǔn)，實驗室應(yīng)該在測量標(biāo)準(zhǔn)、校準(zhǔn)程序、標(biāo)準(zhǔn)砝碼使用和人員資質(zhì)確認(rèn)方面滿足相同的要求。

Table3prescribestheparameters,typicalfrequenciesandtolerancelimitsforthequalificationofbalancesforperiodicandmotivatedinstrumentchecks(LevelIII)andin-useinstrumentchecks(LevelIV)表3天平的周期性主動儀器檢查(第三級)和在用儀器檢查(第四級)建議的參數(shù)，典型的頻次和可接受限度Table3Parametertobechecked檢查參數(shù)Frequency頻次Typicaltolerancelimit接受標(biāo)準(zhǔn)Levelling調(diào)節(jié)水平everydaybeforeweighingbegins每天稱量開始前Acceptancelimitsofthebalance天平的接受標(biāo)準(zhǔn)Internalcalibration(adjustment)(automaticormanual)內(nèi)部校準(zhǔn)(校正)(自動或手動)everydaybeforeweighingbegins每天稱量開始前Automaticacceptancelimitsofthebalance天平的自動接受標(biāo)準(zhǔn)Verification(inusecontrol)檢定(使用控制)Atleastonceaweek至少一周一次OMCLsshalldefinetheirownacceptancecriteriaOMCL應(yīng)該規(guī)定自己的可接受標(biāo)準(zhǔn)Accuracy準(zhǔn)確度FrequencytobedefinedbyOMCL,typicallyonceayear由OMCL規(guī)定頻次，通常一年一次OMCLsshalldefinetheirownacceptancecriteriaOMCL應(yīng)該規(guī)定自己的可接受標(biāo)準(zhǔn)Linearity線性FrequencytobedefinedbyOMCL,typicallyonceayear由OMCL規(guī)定頻次，通常一年一次OMCLsshalldefinetheirownacceptancecriteria(k=1±0.0001)OMCL應(yīng)該規(guī)定自己的可接受標(biāo)準(zhǔn)(k=1±0.0001)Precision精確度FrequencytobedefinedbyOMCL,typicallyonceayear由OMCL規(guī)定頻次，通常一年一次OMCLsshalldefinetheirownacceptancecriteria(SD=maximum5*d)

OMCL應(yīng)該規(guī)定自己的可接受標(biāo)準(zhǔn)(SD=maximum5*d)Eccentricity偏載FrequencytobedefinedbyOMCL,typicallyonceayear由OMCL規(guī)定頻次，通常一年一次OMCLsshalldefinetheirownacceptancecriteria(RSD=0.05%)OMCL應(yīng)該規(guī)定自己的可接受標(biāo)準(zhǔn)(RSD=0.05%)k=correlationcoefficient相關(guān)系數(shù)SD=standarddeviation標(biāo)準(zhǔn)偏差RSD=relativestandarddeviation相對標(biāo)準(zhǔn)偏差ThefollowingqualificationtestsmayalsobeperformedinadditiontothosedescribedinTable3(recommended,notobligatory):除表3中描述的項目，還可以執(zhí)行下述確認(rèn)測試(推薦，非強(qiáng)制)：Parametertobechecked檢查參數(shù)Frequency(recommended)頻次(推薦)Typicaltolerancelimit可接受標(biāo)準(zhǔn)Linearityerror線性誤差onceeverysixmonths每6個月1次OMCLsshalldefinetheirownacceptancecriteria(<accuracyofthebalances)OMCL應(yīng)該規(guī)定自己的可接受標(biāo)準(zhǔn)金天平的準(zhǔn)確度)Drifttest漂移測試onceeverysixmonths每6個月1次OMCLsshalldefinetheirownacceptancecriteria(RSD=0.05%)OMCL應(yīng)該規(guī)定自己的可

接受標(biāo)準(zhǔn)(RSD=0.05%)Minimumweight最小稱量onceayear每年1次OMCLsshalldefinetheirownacceptancecriteriadependingonthetypeofthebalanceOMCL應(yīng)該規(guī)定自己的可接受標(biāo)準(zhǔn)，取決于天平類型Measurementuncertainty測量不確定度onceayear每年1次OMCLsshalldefinetheirownacceptancecriteriadependingonthetypeofthebalanceOMCL應(yīng)該規(guī)定自己的可接受標(biāo)準(zhǔn)，取決于天平類型QUALIFICATIONPROCEDURE確認(rèn)程序Verification校準(zhǔn)Verificationofthebalanceisperformedbyplacingasuitableweight(dependingonthetypeofbalance)inthecentreoftheweighingpanonceandcomparingtheresultwithpre-definedacceptancecriteria.Thesameweightshouldalwaysbeusedintheseverifications.TheacceptancecriteriashallbedefinedbyeachindividualOMCL.天平的校準(zhǔn)就是把合適的砝碼(取決于天平的類型)放置在秤盤中央進(jìn)行一次稱量，然后和預(yù)定的可接受標(biāo)準(zhǔn)比較。在這些檢查中，應(yīng)始終使用相同的砝碼。可接受標(biāo)準(zhǔn)應(yīng)該由每個OMCL單獨規(guī)定。Accuracy準(zhǔn)確度Theaccuracyofthebalanceischeckedbyweighingatleastthreedifferentcertifiedweightsthatcovertheusualweighingrangeofthebalance.Itisrecommendedthattheweightshaveapproximately5%,50%and100%ofthemaximumcapacityofthebalance(orofthemaximumweightusedonthebalance),dependingonthetypeofbalance.Itisrecommendedthattheweighingisrepeatedatleast5timesforeveryweight,particularly,whentheresultsshallalsobeusedinthetestforprecision.

TheacceptancecriteriashallbedefinedbyeachindividualOMCL.天平的準(zhǔn)確度檢查應(yīng)選擇涵蓋天平稱量使用范圍的至少3個不同的標(biāo)準(zhǔn)砝碼進(jìn)行稱量。推薦的砝碼為天平最大稱量能力5%，50%和100%的砝碼(或天平使用的最大稱量值)，這取決于天平類型。推薦每個砝碼重復(fù)稱量5次，特別是當(dāng)結(jié)果同時用于評估精確度時。Linearity線性Theresultsobtainedfromaseriesofaccuracycheckscanbeusedtocalculatethecorrelationcoefficientandtocheckforlinearity.Thecorrelationcoefficientiscalculatedbycomparingthenominalandmeasuredmassesoftheweights.TheacceptancecriteriaforthecorrelationcoefficientshallbedefinedbyeachindividualOMCL.(Proposedcriterion:k=1±0.0001).準(zhǔn)確度測試所得系列結(jié)果可以用于計算相關(guān)系數(shù)和檢查線性。相關(guān)系數(shù)通過比較砝碼的標(biāo)稱值和測量值進(jìn)行計算。相關(guān)系數(shù)的可接受標(biāo)準(zhǔn)應(yīng)由各OMCL分別規(guī)定。(建議標(biāo)準(zhǔn):k=1±0.0001).Precision精確度Theprecisionofthebalanceshouldbeverifiedbyweighingatleast5timesaweightthatisequivalenttoapproximately50%ofthemaximumcapacityofthebalance.Itisrecommendedtorepeatthetestwithaweightthatisequivalenttoapproximately5%ofthemaximumcapacityofthebalance,ifthebalanceisusedatthelowerrange.TheacceptancecriteriashallbedefinedbyeachindividualOMCL.(Proposedcriterion:SD=max5*d,whered=(actual)scaleinterval(eg.d=0.1mg)).天平的精確度應(yīng)該使用天平最大量程大約50%的砝碼進(jìn)行確認(rèn)，砝碼稱量至少5次。如果天平在低量程使用，推薦使用天平最大量程大約5%的砝碼重復(fù)該測試。可接受標(biāo)準(zhǔn)應(yīng)該由各OMCL分別規(guī)定。(建議標(biāo)準(zhǔn)：SD=最大5*d，此處d=實際分度值(例如d=0.1mg))Eccentricity偏載Theeccentricitytestshouldbecarriedoutusingaweightequivalenttoatleast30%ofthemaximumcapacityofthebalance(orofthemaximumweightusedonthebalance).Theweightshouldbeplacedbetweenhalfwayto%ofthedistancefromthecentreof

thepantoitsedgeandbemeasuredateachlocationinthefollowingsequencecentre,frontleft,backleft,backright,frontright,and（optional）againcentre.TheacceptancecriteriashallbedefinedbyeachindividualOMCL.（Proposedcriterion:RSDnotmorethan0.05%,calculatedfromallweighingsatdifferentlocationsonthepan）.偏載測試應(yīng)該使用天平最大量程大約30%的砝碼進(jìn)行確認(rèn)（或者實際使用的最大稱量值）。砝碼應(yīng)放置在從秤盤中心到其邊緣一半到3/4的位置，按照如下順序測量每個位置的顯示值：中心、左前、左后、右后、右前和中心（可選）?？山邮軜?biāo)準(zhǔn)應(yīng)該由各OMCL分別規(guī)定。（建議標(biāo)準(zhǔn):在稱盤中不同位置測量結(jié)果的RSD不得過0.05%）Linearityerror線性誤差Linearityerroristestedatleast3timesusingfourweightsofdefinedmasseswhoseaggregatetotalmassisapproximatelyequaltohalfofthemaximumcapacity,dependingonthetypeofbalance.線性誤差應(yīng)使用4個標(biāo)準(zhǔn)砝碼進(jìn)行測定，其合計的總重量約等于最大量程的一半，至少測定3次，取決于天平的類型。First,thecombinedmassofallfourweightsisweighedandrecorded.Then,twosub-setsofweightsaremadeandtheirmassesarerecorded.首先，所有四個砝碼的組合重量被稱量記錄。然后，將砝碼分成兩組，稱量記錄砝碼的重量。Thelinearityerrorofthebalanceisanabsolutevaluecalculatedbythedifferencebetweenthecombinedmassofallfourweightsandthesumofthemassesfromthetwosub-setsofweights,dividedby2.天平的線性誤差是四個砝碼的組合質(zhì)量和兩組砝碼質(zhì)量總和的差值除以2的絕對值。TheacceptancecriteriashallbedefinedbyeachindividualOMCL.（Proposedcriterion:linearityerror<accuracyofthebalances）.可接受標(biāo)準(zhǔn)應(yīng)該由各OMCL分別規(guī)定。（建議標(biāo)準(zhǔn):線性誤差<天平的準(zhǔn)確度）Drifttest漂移測試

Adrifttestisonlyperformedon5,6or7decimalscalebalances.Itiscarriedoutbyrepeatedmeasurements(every5minutesfor30minutes)ofacontrolweight(dependingonthetypeofbalance)inthemorningandafternoon.Themeanmeasurement,standarddeviationandrelativestandarddeviationcanbecalculatedfromtheresultingdata.Thedriftcanalsobeextractedfromthetrendanalysisoftheverificationtest(Table3).TheacceptancecriteriashallbedefinedbyeachindividualOMCL.(Proposedcriterion:RSD=0.05%).僅僅顯示位數(shù)為小數(shù)點后5,6或7位的天平