Designation:D4698−21StandardPracticeforTotalDigestionofSedimentSamplesforChemicalAnalysisofVariousMetals1ThisstandardisissuedunderthefixeddesignationD4698;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoverstwoproceduresforthetotaldiges-tionofsedimentsforsubsequentdeterminationofmetalsbysuchtechniquesasflameatomicabsorptionspectrophotometry,graphite-furnaceatomicabsorptionspectrophotometry,atomicemissionspectroscopy,etc.1.2Thispracticeisapplicableinthesubsequentdetermina-tionofvolatile,semivolatile,andnonvolatilemetalsofsedi-ments.1.3Actualmetalquantitationcanbeaccomplishedbyfol-lowingthevarioustestmethodsoutlinedunderotherappropri-ateASTMstandardsforthemetal(s)ofinterest.Beforeselectingeitherofthedigestiontechniquesoutlinedinthispractice,theusershouldconsulttheappropriatequantitationstandard(s)foranyspecialanalyticalconsiderations,andPrac-ticeD3976foranyspecialpreparatoryconsiderations.1.4Thevaluesstatedininch-poundunitsaretoberegardedasstandard.ThevaluesgiveninparenthesesaremathematicalconversionstoSIunitsthatareprovidedforinformationonlyandarenotconsideredstandard.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.Foraspecifichazardstatement,see15.5.1.6Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D1129TerminologyRelatingtoWaterD1192GuideforEquipmentforSampli...
