Mass Calibrations

1 Page 1 NISTMeasurementServices: NEUNISTPUBLICATION April20,1989 U.S.DepartmentofCommerce NationalInstituteofStandardsandTechnology Open at page → 2 Page 2 CenterforManufacturingEngineering TheCenterforManufacturingEngineeringprovidescompetenceanddevelopstechnicaldata,findings,and standardsinmanufacturingengineering,mechanicalmetrology,automation,robotics,controltechnology,... Open at page → 3 Page 3 NISTMEASUREMENTSERVICES MassCalibrations R.S.Davis PrecisionEngineeringDivision CenterforManufacturingEngineering NationalEngineeringLaboratory NationalInstituteofStandardsandTechnology Gaithersburg,MD20899 January1989 N... Open at page → 4 Page 4 LibraryofCongressCatalogCardNumber:88-600608 NationalInstituteofStandardsandTechnologySpecialPublication250-31 Natl.Inst.Stand.Technol.,Spec.Publ.250-31,72pages(Jan.1989) CODEN:NSPUE2 U.S.GOVERNMENTPRINTINGOFFICE WASHING... Open at page → 5 Page 5 PREFACE Calibrations andrelatedmeasurementservicesoftheNationalInstituteof StandardsandTechnologyprovidethemeansformakersandusersofmeasuring toolstoachievelevelsofmeasurementaccuracythatarenecessarytoattain quality,produ... Open at page → 6 Page 6 proceduresutilizedinconnectionwithNISTServiceIdentification Numbersfrom 22010Cto22180MlistedintheNBSCalibrationServicesUsersGuide1986- 88/Revised(pages28-31). Inquiriesconcerningthecontentsofthesedocuments maybedirectedt... Open at page → 7 Page 7 Contents Page 1.DescriptionofService 1 2.TheInternational SystemofUnits 2 3.MassStandardsinPractice 3 3.1Kilograms 3 3.2OtherDenominations 6 4.DensityDetermination ofSingle-PieceKilograms UsingSubmersibleBalance 7 4.1App... Open at page → 8 Page 8 7.1MeasurementAlgorithm 15 7.2UncertaintyofValueofStandardWeights 16 8.QualityControl 16 8.1F-Test 19 8.2t-Test 19 8.3Between-Times Components 23 9.FuturePlans 23 10.References 25 Appendices A.LeastSquaresAnalysis Al B.S... Open at page → 9 Page 9 1.DescriptionofService TheNationalBureauofStandardsmaintainsthenationalstandardformassin theformoftheprototypekilogramK20anditscompanionK4andprovides servicestosupportthesegmentsofthenationalmeasurementsystemwhichrely di... Open at page → 10 Page 10 establishedforNBSClassesA,B,M,orS-1priortosubmission [1 ] . 1Normally weightsareavailablefrommanufacturers, manyofwhomcanfurnishdirectly documentation suitableformeetingqualityassurancecontractsand requirements . Individ... Open at page → 11 Page 11 unitofmass,however,therehasbeennochangeinthedefinitionforalmost 100years. TheunitofmassintheSIisthekilogram. Itsvalueisdefinedwith referencetoanobjectknownastheInternational PrototypeKilogram(IPK) . Thedefinitioncanbesim... Open at page → 12 Page 12 Asidefromthefactthatplatedbrassorstainlesssteelarenotasresistant tochemicalattackasisplatinum/iridium, themajordifferencebetween kilogramsmadeofPt/Irandthoseofbrassorsteelistheirsize,more specificallytheirvolume. Onekilo... Open at page → 13 Page 13 B. Figure1.A.Astainless-steel kilogram(density8000kg/m-^)balancesa platinum-iriditunkilogram(density21500kg/m-^)atnormal atmosphericconditions. B.Undervacuumconditionsonecan seethatthemassofthestainless-steelkilogramactu... Open at page → 14 Page 14 Thetwoconventions inwidestuseare:density8.0g/cm-^at20°Cinairof density1.2g/cm^ ;anddensity8.39094 g/cvsr'at20°Cinairofdensity1.2 g/cm3[7]. MassinSIunitsistrulymass(or"vacuum"massor"true"mass) .Whenthe NationalBureauofSta... Open at page → 15 Page 15 calibrations were,ofcourse,donebeforethedaysofelectronicbalances. Eventoday,higherprecisioncanusuallybeobtainedwithmechanicalbalances althoughwithagreatlossinconvenience. Usinganequal-armbalance,for instance,onewouldneed... Open at page → 16 Page 16 4.1Apparatus ThebalancemodifiedforthisworkisaMettlerPL1200, theimportant specifications ofwhichare: weighingrange 0 -1200 g reproducibility <0.005 g linearity <0.01 g Significantmechanicalandelectronicmodifications werei... Open at page → 17 Page 17 Figure2.Cross-sectionalviewofthebalanceImmersedInIts thermostatedbath.Aconventionally-shapedstandardweightis shownonthepan.Unconventional loadsmayalsobe accommodatedbythepanassuggestedbythesphere(drawnwith dashedlines) .... Open at page → 18 Page 18 Table1.ComparisonofPropertiesofFC-75andWater Property(at25"C) FC-75 Water Density(kg/m-^) loUU 1AAA lUUO Coefficientofexpansion("C^) 1.6x10 3 2.5x10 4 Kinematicviscosity(cm/s) 0.oZXlO 2 0.89x10 2 Vaporpressure(Pa) 4000 3... Open at page → 19 Page 19 Theproblemwithusingeq(2)isthattheprecisionwithwhich canbe measuredfarexceedstheaccuracywithwhichpisknown. Thus,forbest results,oneshouldalsomeasureanobjectwhosemassandvolumeareknown. Placingsuchanobjectonthebalanceessent... Open at page → 20 Page 20 5.2CleaningProcedures 5.2.1One-PieceWeights One-pieceweights, 1gramandlarger,aregenerallysteamcleaned. Theweights areeitherheldorplacedinajetofsteamandmanipulated sothattheentire surfaceoftheweightissubjectedtothecleanin... Open at page → 21 Page 21 5.2.3Sheet-MetalWeights First,theweightsareplacedinanacetonebathagitatedtohelploosenany foreignmaterial. Asoftbrush,suchasacamelhairbrush,maybeusedto agitatetheweights. Theweightsareremovedfromtheacetone,allowedtodry and... Open at page → 22 Page 22 5.5Brushes Brushesrequirespecialattentionbecausetheyareeasilycontaminatedand oftenarethelastcleaninginstrumentusedbeforetheweightsarecalibrated. Onlysoftbrushes,suchascamelhairbrushesareusedonweights. Thebrushesarecleane... Open at page → 23 Page 23 Themassoftheunknowniscomputedtobe: Di -pV^+A -pV^ - +S3 -S^) S3-S2 M= ; 7z X 1-p/D X Where =thecalibratedmassof I>i Ml=thevolumeof A=themassofthesensitivityweight =thevolumeofthesensitivityweight Dx=thedensityoftheunknow... Open at page → 24 Page 24 Therestoftheweightsinthesetarecalibratedinaself-consistentmanner usingtheweightcalibratedinstep1asthestandard. Itisconvenient tocalibrateasetofweightsadecadeatatime,usingasa comparatorthemostsensitivebalanceavailablewhic... Open at page → 25 Page 25 Table2.Capacitiesandstandarddeviationsofbalancesus BalanceCapacity StandardDeviation 3a 6 0 . .0005"'6 20 0..0024 40 0 , ,0039 160 0014 1kg 0,,032 10 2,,5 mg 30 8,.2 1lb 0,,031 /ilb 6 0,,46 50 5,,5 mg 2500 0.,002lb 30000... Open at page → 26 Page 26 Table3.Typicalrandomcomponentsofcalibrationuncertainties Nom.Val Uncertainty 1000 g 500 300 200 100 50 30 20 10 5 3 2 1 0.072mg 0.059 0.057 0.050 0.058 0.035 0.029 0.024 0.026 0.013 0.0082 0.0061 0.0049 500mg 300 200 100... Open at page → 27 Page 27 intercompare theunknownswiththestandards. Tocontrolthequalityofthis measurementsystem,wemustinsurethatthemassofthestartingstandardsdoes notchangeandthattherandomerrorofthebalancesusedhasnotdeteriorated fromitsacceptedval... Open at page → 28 Page 28 BALANCL 12 OUTLIERCODE:CHKSTD=C.STDDEV=S.BOTH=0 H 1 1 1 1 1 1 1 1 1 .1147E+0e+ .8557E-ei+ •2 .5641E-ei+ •2. • » 2 • 2. 2 . 2 22 . 22. ••222. 2».» 2 22. 25.».••2.22. 2. •2* •.••••42.• •22 * 36 24 •3.*•••«• 2 . • • •••2. .... Open at page → 29 Page 29 CHECKs.aNDARO41 BALANCE 12 I 1 1 -.1932E+02+ .1938E+02+ .1943E+02+ -.1949E+e2+ •• 22 • _ 2«• • •2 • • • 2 • • 2 • •• • • • •3 • • •2 • • •2*2 3• • •2 • • ••• • • • «« 2 • • •• • • • • •• • ••2 • • • • 2 2 • • • • 2 3 • •... Open at page → 30 Page 30 CHECK ..^fiD -.4752E-01+ OUTLIEK — I jE:CHKSTO-C.STODEV=S,BOTH.=0 -.5*07E-ei+ -.6063E-01+ -.6718E-01+ 2 .22 32. . 2.222. . .6345322 .5533. 235.22 2559223. .462224. 254323. 333.32 22 . 2 . . 2.2 . 4.33 .2 5.2. 2 .. 222. .... Open at page → 31 Page 31 processeswhichchangeNlandN2innearlyidenticalamounts. However,Nland N2areusedtocalibrateweightsetswhichoftenincludethedecadefrom1kg to100g.Everytimeweightsinthisdecadearecalibrated, theresultsare checkedwitha100-gchecksta... Open at page → 32 Page 32 2.Anexistingkilogramcomparatorhasbeenreconditioned andpartially automatedsothatitsstandarddeviationismorethan15timeslessthan thatofthecomparatorusedforroutinecalibrations. Thus,iftherewere nobetween-timescomponents, itwo... Open at page → 33 Page 33 10.References [1]Lashof,T.W.andMacurdy, L.B.,PrecisionLaboratoryStandardsof MassandLaboratoryWeights. NBSCircular547,Section 1(1954 August). ReprintedasNBSIR78-1476(1978October). [2]ASTME617-81StandardSpecification forLa... Open at page → 35 Page 35 AppendixA LEASTSQUARESANALYSIS[8] Webeginthenwithasetofnobservations, yi,y2i • • •Yn involvingk objectswherevalues, /S^ >^^2 > • • • ^°^®determined. Thesetof observations canberepresentedbytheequationsfortheirexpectedval... Open at page → 36 Page 36 3 -1 -1 -1 1 -1 3 -1 1 3 1 -1 -1 1 -1 -1 3 |8 = yi+72+73 -yi+y4+ys -72+y4+ys L-y3+y4+ye A A* A A A wherePisthecolumnvectorwithelements ,pi, ^93,^84,thecaretbeing usedtodenotethefactthatthevaluesarefunctionsoftheobservati... Open at page → 37 Page 37 where orinmatrixnotation n n 'X'X r X'y r' 0 A. Thesolutionmaybewrittenoutformallyasfollows: CX' h h'X' 0 ' C h ^ ' X'y ^ f .h' 0 , V y (5) (6) Tofacilitatecomputation itisconvenientt9havethevalues, writtenout aslinearfu... Open at page → 38 Page 38 2 2 s= ; r y(deviations). (9) (deviation). =y. "(x.^J^+ ^^^^^ . . .x.^^^) Onecanwritethesedeviationsa§afunctionoftheobservationsbynotingthat thepredictedvaluesarejust X/9andthedeviationsarethus dev=y - =y -X[CX',h](m]=y... Open at page → 39 Page 39 Further,thedesirabilityofadesigndependssomewhatontherestraintbeing used. Insomecases,one'sjudgmentofadesignchangesdependingonwhether onestartswithasummationasknown(e.g.,5+3+2)andworksdown,orwith aunitasknownandworksup(e.... Open at page → 41 Page 41 AppendixB SampleCalibrationReport Thefollowingisafullcalibrationreportforasetofweightswith denominations from1gto1mg. Bl Open at page → 42 Page 42 U.S.DEPARTMENTOFCOMMERCE NATIONALBUREAUOFSTANDARDS NATIONALMEASUREMENTLABORATORY GAITHERSBURG, MD.20899 ' REPORT 0F MASSVALUES COMPANYX LOCUS,U.S.A. SETOFMASSSTANDARDS :500MG-IMG SERIALNUMBER00001 MANUFACTURER :COMPANYY... Open at page → 43 Page 43 COMPANYX PAGE 1 LOCUS,U.S.A. SETOFMASSSTANDARDS :500MG-IMG TESTNUMBERDEMOl INTRODUCTION THISDOCUMENTISACOMPREHEN- SIVEREPORTCOVERINGTHESEQUENCE OFOPERATIONSUSEDTOASSIGNMASS VALUES TOTHEWEIGHTSIDENTIFIED ABOVE. ITINCLUDES... Open at page → 44 Page 44 COMPANYX PAGE 2 LOCUS,U.S.A. SETOFMASSSTANDARDS :500MG-IMG TESTNUMBER DEMOl WEIGHINGDESIGN ONLYDIFFERENCES INMASSCAN BEMEASURED, THEREFORE THEMASS VALUESFORTHE'UNKNOWN'WEIGHTS MUSTBEDETERMINED BYCOMPARISON WITH OTHERWEIG... Open at page → 45 Page 45 COMPANYX PAGE 3 LOCUS,U.S.A. SETOFMASSSTANDARDS :500MG -IMG TESTNUMBERDEMOl POSSESSTHEPROPERTIESOFRANDOM- NESSASSOCIATED WITHINDEPENDENT MEASUREMENTS FROM A STABLE PROBABILITY DISTRIBUTION. THE REPORTED 'FRATIO'AND 'TVAL... Open at page → 46 Page 46 COMPANYX PAGE A LOCUS,U.S.A. SETOFMASSSTANDARDS :500MG-IMG TESTNUMBERDEMOl ABALANCEUNDERSTABLEOPERA- TINGCONDITIONS WILLEXHIBIT A CERTAINCHARACTERISTIC VARIABILITY WHICHCANBEDESCRIBED BYTHE STANDARD DEVIATION FOR SUCH ME... Open at page → 47 Page 47 COMPANYX PAGE 5 LOCUS,U.S.A. SETOFMASSSTANDARDS :500MG -IMG TESTNUMBERDEMOl REFERENCES THEFOLLOWINGREFERENCESARESUGGESTEDFORDETAILEDDESCRIPTIONOF PORTIONSOFTHISREPORT ,ANDFORGENERALINFORMATIONCONCERNINGTHE MASSMEASUREMEN... Open at page → 48 Page 48 COMPANYX PAGE 6 LOCUS,U.S.A. SERIES 1 SETOFMASSSTANDARDS :500MG -IMG 8/29/ 86 TESTNUMBERDEMOl BALANCE 2 OPERATOR 39 ACCEPTEDWITHINSTANDARDDEVIATIONOFTHEPROCESS 0.002A0MG ACCEPTEDBETWEENSTANDARDDEVIATIONOFTHEPROCESS 0.000... Open at page → 49 Page 49 COMPANYX PAGE 7 LOCUS,U.S.A. SERIES 1 SETOFMASSSTANDARDS :500MG -IMG 8/29/ 86 TESTNUMBERDEMOl BALANCE 2 OPERATOR 39 CALIBRATIONDESIGN 41 GRAMS 111 A 1 + A2 + A3 + A 4 + - A 5 + A6 + R + " OBSERVATIONS INDIVISIONS DOUBLES... Open at page → 50 Page 50 COMPANYX PAGE 8 LOCUS,U.S.A. SERIES 1 SETOFMASSSTANDARDS :500MG-IMG 8/29/ 86 TESTNUMBERDEMOl BALANCE 2 OPERATOR 39 CALIBRATIONDESIGN «1 SENSITIVITYWEIGHT MASS 4.99198MG VOLUME 0.00185CM3AT20C COEFFICIENTOFEXPANSION 0.000... Open at page → 51 Page 51 COMPANYX PAGE 9 LOCUS,U.S.A. SERIES 1 SETOFMASSSTANDARDS :500MG -IMG 8/29/ 86 TESTNUMBERDEMOl BALANCE 2 OPERATOR 39 MAXIMUMLOAD 1.0000G STARTINGRESTRAINTNUMBER 4 CALIBRATIONDESIGN «1 PRECISIONCONTROL OBSERVEDSTANDARDDEVI... Open at page → 52 Page 52 COMPANYX PAGE10 LOCUS,U.S.A. SERIES2 SETOFMASSSTANDARDS :500MG-IMG 8/29/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 ACCEPTEDWITHINSTANDARDDEVIATIONOFTHEPROCESS 0.00050MG ACCEPTEDBETWEENSTANDARDDEVIATIONOFTHEPROCESS 0.0000... Open at page → 53 Page 53 COMPANYX PAGE LOCUS,U.S.A. SERIES SETOFMASSSTANDARDS :500MG -IMG 8/29/ TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 CALIBRATIONDESIGN 62 MG 500 300 200 100 100 100 A 1 + + A2 + + A 3 + + A It + A 5 + A6 + + A 7 -+ + A8 + + A9... Open at page → 54 Page 54 COMPANYX PAGE12 LOCUS,U.S.A. SERIES2 SETOFMASSSTANDARDS :500MG-IMG 8/29/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 CALIBRATIONDESIGN 62 SENSITIVITYWEIGHT MASS 10.00000MG VOLUME 0.00000CM3AT20C COEFFICIENTOFEXPANSION 0.00... Open at page → 55 Page 55 COMPANYX PAGE13 LOCUS,U.S.A. SERIES2 SETOFMASSSTANDARDS :500MG -IMG 8/29/ 85 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 CALIBRATIONDESIGN 62 SUM WEIGHTSUSEDFORTHELINEARCOMBINATIONS (MG) MG 500300200100 1000 + + + 900 + + + 8... Open at page → 56 Page 56 COMPANYX . PAGElA LOCUS,U.S.A. SERIES2 SETOFMASSSTANDARDS :500MG-IMG 8/29/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 MAXIMUMLOAD 0.6000G STARTINGRESTRAINTNUMBER 4 CALIBRATIONDESIGN 62 PRECISIONCONTROL OBSERVEDSTANDARDDEV... Open at page → 57 Page 57 COMPANYX PAGE15 LOCUS,U.S.A. SERIES3 SETOFMASSSTANDARDS :500MG -IMG 8/30/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 ACCEPTEDWITHINSTANDARDDEVIATIONOFTHEPROCESS 0.00050MG ACCEPTEDBETWEENSTANDARDDEVIATIONOFTHEPROCESS 0.000... Open at page → 58 Page 58 COMPANYX PAGE 1 LOCUS,U.S.A. SERIES SETOFMASSSTANDARDS :500MG-IMG 8/30/ TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 CALIBRATIONDESIGN 62 MG 50 30 20 10 10 10 A 1 + + A2 + + A 3 + + A A + A5 + A6 + + A 7 + + A8 + + A9 + A10 +... Open at page → 59 Page 59 COMPANYX PAGE17 LOCUS,U.S.A. SERIES 3 SETOFMASSSTANDARDS :500MG -IMG 8/30/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 CALIBRATIONDESIGN 62 SENSITIVITYWEIGHT MASS 10.00000MG VOLUME 0.00000CMSAT20C COEFFICIENTOFEXPANSION 0.... Open at page → 60 Page 60 COMPANYX PAGE18 LOCUS,U.S.A. SERIES3 SETOFMASSSTANDARDS :500MG-IMG 8/30/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 CALIBRATIONDESIGN 62 SUM WEIGHTSUSEDFORTHELINEARCOMBINATIONS (MG) MG 50 30 20 10 10 10 100++ + 90 + + + 8... Open at page → 61 Page 61 COMPANYX PAGE19 LOCUS,U.S.A. SERIES 3 SETOFMASSSTANDARDS :500MG -IMG 8/30/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 MAXIMUMLOAD 0.0600G STARTINGRESTRAINTNUMBER 4 CALIBRATIONDESIGN 62 PRECISIONCONTROL OBSERVEDSTANDARDDEV... Open at page → 62 Page 62 COMPANYX PAGE20 LOCUS,U.S.A. SERIES4 SETOFMASSSTANDARDS :500MG-IMG 8/30/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 ACCEPTEDWITHINSTANDARDDEVIATIONOFTHEPROCESS 0.00050MG ACCEPTEDBETWEENSTANDARDDEVIATIONOFTHEPROCESS 0.0000... Open at page → 63 Page 63 COMPANYX PAGE2 LOCUS,U.S.A. SERIES SETOFMASSSTANDARDS :500MG -IMG 8/30/ TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 CALIBRATIONDESIGN 62 MG 5 3 2 1 A 1 + - - + A2 + A3 + - - - A 4 + - - A 5 + - - A6 + - + A 7 ' + - - A8 + - -... Open at page → 64 Page 64 COMPANYX PAGE22 LOCUS,U.S.A. SERIES A SETOFMASSSTANDARDS :500MG-IMG 8/30/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 CALIBRATIONDESIGN 62 SENSITIVITYWEIGHT MASS 10.00000MG VOLUME 0.00000CM3AT20C COEFFICIENT OFEXPANSION 0.... Open at page → 65 Page 65 COMPANYX LOCUS,U.S.A. SETOFMASSSTANDARDS TESTNUMBERDEMOl 500MG-IMG PAGE23 SERIES A 8/30/ 86 BALANCE OPERATOR 13 39 CALIBRATIONDESIGN 62 SUM (MG) 10 9 8 7 6 5 4 3 2 1 WEIGHTSUSEDFORTHELINEARCOMBINATIONS MG VALUESANDUNCERT... Open at page → 66 Page 66 COMPANYX PAGE2 A LOCUS,U.S.A. SERIESA SETOFMASSSTANDARDS :500MG-IMG 8/30/ 86 TESTNUMBERDEMOl BALANCE 13 OPERATOR 39 MAXIMUMLOAD 0.0060G STARTINGRESTRAINTNUMBER « CALIBRATIONDESIGN 62 PRECISIONCONTROL OBSERVEDSTANDARDDEVI... Open at page → 67 Page 67 COMPANYX PAGE25 LOCUS,U.S.A. 8/30/ 66 SETOFMASSSTANDARDS :500MG-IMG TESTNUMBERDEMOl SUMMARY FORCONVENIENCE, THERESULTS OFTHISWORKARESUMMARIZED IN TABLES IAND II. THEVALUES ASSIGNEDAREWITHREFERENCETOTHE STANDARDSIDENTIFIE... Open at page → 68 Page 68 COMPANYX PAGE2 LOCUS,U.S.A. 8/30/ SETOFMASSSTANDARDS :500MG-IMG TESTNUMBER S ONITSTRUEMASSORWEIGHT IN VACUO . CORRECTION B -'APPARENTMASS VERSUSDENSITY8.0'ISDETERMINED BYAHYPOTHETICALWEIGHINGOFTHE WEIGHT,INAIRHAVINGADENS... Open at page → 69 Page 69 COMPANYX PAGE LOCUS,U.S.A. 8/30/ SETOFMASSSTANDARDS :500MG-IMG TESTNUMBERDEMOl TABLEI MASS UNCERTAINTY VOLAT20COEFOF ITEM (G) (G) (CM3) 500MG .«9992233 0 ..00000300 0 ,.030120.000020 300MG .29995722 0 ,.00000185 0 ,.0180... Open at page → 70 Page 70 COMPANYX PAGE28 LOCUS,U.S.A. 8/30/ 86 SETOFMASSSTANDARDS :500MG -IMG TESTNUMBERDEMOl TABLEII ITEM COR.A(MG) COR.B(MG) NEW 500MG 300MG 200MG lOOMG 50MG 30MG 20MG lOMG 5MG 3MG 2MG IMG - .04231 - .02158 - .02465 .00879 .000... Open at page → 71 Page 71 AppendixC SurveillanceTest Thefollowingisthereportofasurveillance test[7].Subsequenttoa calibrationsuchasthatshowninAppendixB,weightsmayberesubmitted forperiodicsurveillance. Surveillance isamorerapidandlesscostly proced... Open at page → 72 Page 72 UNITEDSTATESDEPARTMENTOFCOMMERCE NationalBureauofStandards Gaithersburg.Maryland20099 September 18,1986 Inreplyreferto: Subject: Items: Theaboveitemshavebeenintercomparedinsums. Thedifferences asmeasured havebeencompared... Open at page → 73 Page 73 AppendixD CalibrationofDeadWeights Thefollowingisatypicalreportofcalibrationforasetofdead weights . Dl Open at page → 74 Page 74 (i*cv.txm) U.S.DEPARMENTOFCOMMERCE NATIONALBUREAUOfSTANDARDS OAlTHiRSBURG.MARYLAND20e*t REPORTOFCALIBRATION NBSTestNumber: For: Items: Theabove ofmass. itemshavethemassvaluesshownwithreferencetotheNBS Item Mass (g) Uncer... Open at page → 75 Page 75 TheNationalBureauofStandardsusesthefollowingrelationshipbetweenthe metricunitofmassandtheU.S.customaryunitofmass: onepound (avoirdupois) equals0.'i^5359237kilogram. FortheDirector, NationalMeasurementLaboratory JoeD.Simm... Open at page → 77 Page 77 NBS-n4AIREV.2-BC) U.S.DEPT.OFCOMM. BIBLIOGRAPHICDATA SHEET(Seeinstructions) 1.PUBLICATIONOR REPORTNO. NIST/SP-250/31 2.PerformingOrgan.ReportNo,3.PublicationDate January1989 4.TITLEANDSUBTITLE NISIMeasurementServices:Mas... Open at page → 79 Page 79 THESP250SERIESONNISTMEASUREMENTSERVICES* SP250-1 SpectralRadianceCalibrations SN003-003-02792-8 $3.50 SP250-2 FarUltravioletDetectorStandards PB87227609 SP250-3 RadiometricStandardsintheVacuum Ultraviolet SN003-0G3-02806... Open at page → 80 Page 80 U.S.DepartmentofCommerce NationalInstituteofStandardsandTechnology (formerlyNationalBureauofStandards) Gaithersburg,MD20899 OfficialBusiness PenaltyforPrivateUse$300 Open at page →