Designation:D6129−97(Reapproved2021)StandardTestMethodforSiliconinEngineCoolantConcentratesbyAtomicAbsorptionSpectroscopy1ThisstandardisissuedunderthefixeddesignationD6129;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationofsiliconintherangefrom200ppmto500ppminenginecoolantconcentratesbyatomicabsorption.Thismethodisasaccurateandpreciseasphotometricmethods,whilerequiringconsider-ablylessoperatortimeandavoidingproblemswithreagentinstability.1.1.1Coolantswithsiliconcontentoutsideofthisrangemaybeanalyzedbythismethodbysuitablyadjustingthesamplesize.Careshouldbetakentoensurethattheglycolcontentoftheworkingstandardscorrespondstothatofthesamplesolutionbeinganalyzed.1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D1176PracticeforSamplingandPreparingAqueousSolu-tionsofEngineCoolantsorAntirustsforTestingPurposes3.SummaryofTestMethod3.1Thesampleisdissolvedinwaterandthesiliconcontentisdeterminedfromastandardcurveestablishedatthetimethesampleisrun.Anatomicabsorptionspectrometerwithanitrousoxide-acetyleneflameisused.4.Apparatus4.1AtomicAbsorptionSpectrometer,withnitrousoxide-acetyleneflame.4.2Hollow-Cath...
