Designation:D7419−18StandardTestMethodforDeterminationofTotalAromaticsandTotalSaturatesinLubeBasestocksbyHighPerformanceLiquidChromatography(HPLC)withRefractiveIndexDetection1ThisstandardisissuedunderthefixeddesignationD7419;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoversthedeterminationoftotalaromaticsandtotalsaturatesinadditive-freelubebasestocksusinghighperformanceliquidchromatography(HPLC)withrefractiveindex(RI)detection.Thistestmethodisapplicabletosamplescontainingtotalsaturatesintheconcentrationrangeof74.9%to100.0%bymassandaromaticsintheconcentra-tionrangeof0.0%to25.1%bymass.Theprecisionisexpressedintermsofthetotalsaturates.1.1.1Polarcompounds,ifpresent,arecombinedwiththetotalaromatics.Precisionwasdeterminedforbasestockswithpolarscontent<1.0%bymass.1.2ThistestmethodincludesarelativebiassectionfortotalsaturatesinbasestocksbasedonaPracticeD6708accuracyassessmentbetweenTestMethodD7419andTestMethodD2007.Thederivedcorrelationequationisonlyapplicableforbasestocksinthetotalsaturatesconcentrationrangefrom75.0%to100.0%bymassasmeasuredbyTestMethodD7419.1.2.1TheapplicablerangefortotalsaturatesbyTestMethodD2007isfrom71.0%to99.0%bymassasreportedbyTestMethodD2007.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedb...