Designation:D6822−12bManualofPetroleumMeasurementStandards(MPMS),Chapter9.3StandardTestMethodforDensity,RelativeDensity,andAPIGravityofCrudePetroleumandLiquidPetroleumProductsbyThermohydrometerMethod1ThisstandardisissuedunderthefixeddesignationD6822;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoversthedetermination,usingaglassthermohydrometerinconjunctionwithaseriesofcalculations,ofthedensity,relativedensity,orAPIgravityofcrudepetroleum,petroleumproducts,ormixturesofpetroleumandnonpetroleumproductsnormallyhandledasliquidsandhavingaReidvaporpressuresof101.325kPa(14.696psi)orless.Valuesaredeterminedatexistingtemperaturesandcorrectedto15°Cor60°Fbymeansofaseriesofcalculationsandinternationalstandardtables.1.2Theinitialthermohydrometerreadingsobtainedareuncorrectedhydrometerreadingsandnotdensitymeasure-ments.Readingsaremeasuredonathermohydrometerateitherthereferencetemperatureoratanotherconvenienttemperature,andreadingsarecorrectedforthemeniscuseffect,thethermalglassexpansioneffect,alternatecalibrationtem-peratureeffectsandtothereferencetemperaturebymeansofcalculationsandAdjuncttoD1250GuideforUseofthePetroleumMeasurementTables(APIMPMSChapter11.1).1.3Readingsdeterminedasdensity,relativedensity,orAPIgravitycanbeconvertedtoequivalentvaluesintheotherunitsoralternatereferencetemperaturesbymeansofInterconver-sionProcedures(APIMPMSChapter11.5)orAdjuncttoD1250GuideforUseofthePetroleumMeasurementTables(APIMPMSChapter11.1),orboth,ortablesasapplicable.1.4Theinitialthermohydrometerreadingshallberecordedbeforeperforminganycalculations.ThecalculationsrequiredinSection9shallbeappliedtotheinitialthermohydrometerreadingwithobservationsandresultsreportedasrequiredbySection11priortouseinasubsequentcalculationprocedure(measurementticketcalculation,met...
