Designation:D4323−21StandardTestMethodforHydrogenSulfideintheAtmospherebyRateofChangeofReflectance1ThisstandardisissuedunderthefixeddesignationD4323;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoverstheautomaticcontinuousdeter-minationofhydrogensulfide(H2S)intheatmosphereoringaseoussamplesintherangefromonepartperbillionbyvolume(1ppb/v)to3000ppb/v.Informationobtainedmaybeusedforair-pollutionstudies,fence-linemonitoring,andothersourceemissionmonitoring.1.2Therangemaybeextendedbyappropriatedilutiontechniquesorbyequipmentmodification.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Thevaluesgiveninparenthesesaremathematicalconversionstoinch-poundunitsthatareprovidedforinforma-tiononlyandarenotconsideredstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.(SeeSection9forspecificsafetyprecautionarystatements.)1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D1193SpecificationforReagentWaterD1356TerminologyRelatingtoSamplingandAnalysisofAtmospheresD2420TestMethodforHydrogenSulfideinLiquefiedPetroleum(LP)Gases(LeadAcetateMethod)D2725TestMethodforHydrogenSulfideinNaturalGas(MethyleneBlueMethod)(Withdrawn1996)3D3609PracticeforCalibrationTechniquesUsingPerme-ationTubesD4084TestMethodforAnalysisofHydrogenSulfideinGaseousFuels(LeadAcetateReactionRateMethod)D43...
