Designation:D2791−13StandardTestMethodforOn-lineDeterminationofSodiuminWater1ThisstandardisissuedunderthefixeddesignationD2791;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoverstheon-linedeterminationoftraceamountsofsodiuminwaterusinganion-selectiveelectrode.1.2Thistestmethodisbasedonon-lineapplicationofthesodiumionelectrodeasreportedinthetechnicalliterature(1-3).2Itisgenerallyapplicableovertherangeof0.01to10000µg/L.1.3TheanalystshouldbeawarethatadequatecollaborativedataforprecisionandbiasstatementsasrequiredbyPracticeD2777arenotprovided.SeeSection16fordetails.1.4ThevaluesstatedinSIunitsaretoberegardedasstandard.Theinch-poundunitsgiveninparenthesesareforinformationonly.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.ForspecifichazardstatementsseeSection6.2.ReferencedDocuments2.1ASTMStandards:3D1066PracticeforSamplingSteamD1129TerminologyRelatingtoWaterD1193SpecificationforReagentWaterD1293TestMethodsforpHofWaterD2777PracticeforDeterminationofPrecisionandBiasofApplicableTestMethodsofCommitteeD19onWaterD3864GuideforOn-LineMonitoringSystemsforWaterAnalysisD3370PracticesforSamplingWaterfromClosedConduitsD5540PracticeforFlowControlandTemperatureControlforOn-LineWaterSamplingandAnalysis3.Terminology3.1Definitions—Fordefinitionsoftermsusedinthistestmethod,refertoTerminologyD1129.4.SignificanceandUse4.1Sodiumisapervasivecontaminantanditisthefirstcationtobreakthroughdeionizationequipment.Thistestmethodallowsmeasurementofmicrogramsperlitre(partsperbillion)concentrationsofsodiuminwatertomonitorlow-sodiumwatersourcesforindicationsofcontaminationorp...
