Designation:D4628−14StandardTestMethodforAnalysisofBarium,Calcium,Magnesium,andZincinUnusedLubricatingOilsbyAtomicAbsorptionSpectrometry1ThisstandardisissuedunderthefixeddesignationD4628;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope*1.1Thistestmethodisapplicableforthedeterminationofmasspercentbariumfrom0.005to1.0%,calciumandmagnesiumfrom0.002to0.3%,andzincfrom0.002to0.2%inlubricatingoils.1.2Higherconcentrationscanbedeterminedbyappropriatedilution.Lowerconcentrationsofmetalssuchasbarium,calcium,magnesium,andzincatabout10ppmlevelcanalsobedeterminedbythistestmethod.Useofthistestmethodforthedeterminationattheselowerconcentrationsshouldbebyagreementbetweenthebuyerandtheseller.1.3Lubricatingoilsthatcontainviscosityindeximproversmaygivelowresultswhencalibrationsareperformedusingstandardsthatdonotcontainviscosityindeximprovers.1.4ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.Specificwarningstatementsaregivenin3.1,6.3,and8.1.2.ReferencedDocuments2.1ASTMStandards:2D6299PracticeforApplyingStatisticalQualityAssuranceandControlChartingTechniquestoEvaluateAnalyticalMeasurementSystemPerformance3.SummaryofTestMethod3.1Asampleisweighedandbaseoilisaddedto0.2560.01-gtotalmass.Fiftymillilitresofakerosinesolution,containingpotassiumasanionizationsuppressant,areadded,andthesampleandoilaredissolved.(Warning—Hazardous.Potentiallytoxicandexplosive.)Standardsaresimilarlyprepared,alwaysaddingoilifnecessarytoyie...
