EPA Method 306A

2144METHOD306A-DETERMINATIONOFCHROMIUMEMISSIONSFROMDECORATIVEANDHARDCHROMIUMELECTROPLATINGANDCHROMIUMANODIZINGOPERATIONSNOTE:Thismethoddoesnotincludeallofthespecifications(e.g.,equipmentandsupplies)andprocedures(e.g.,samplingandanalytical)essentialtoitsperformance.Somematerialisincorporatedbyreferencefromothermethodsin40CFRPart60,AppendixAandinthispart.Therefore,toobtainreliableresults,personsusingthismethodshouldhaveathoroughknowledgeofatleastMethods5and306.1.0ScopeandApplication.1.1Analyte.Chromium.CASNumber[7440-47-3].1.2Applicability.1.2.1Thismethodappliestothedeterminationofchromium(Cr)inemissionsfromdecorativeandhardchromiumelectroplatingfacilities,chromiumanodizingoperations,andcontinuouschromiumplatingatironandsteelfacilities.ThemethodislessexpensiveandlesscomplextoconductthanMethod306.Correctlyapplied,theprecisionandbiasofthesampleresultsshouldbecomparabletothoseobtainedwiththeisokineticMethod306.Thismethodisapplicableforthedeterminationofairemissionsundernominalambientmoisture,temperature,andpressureconditions.21451.2.2Themethodisalsoapplicabletoelectroplatingandanodizingsourcescontrolledbywetscrubbers.1.3DataQualityObjectives.1.3.1PretestProtocol.1.3.1.1Thepretestprotocolshoulddefineandaddressthetestdataqualityobjectives(DQOs),withallassumptions,thatwillberequiredbytheenduser(enforcementauthority);whatdataareneeded?whyarethedataneeded?howwilldatabeused?whataremethoddetectionlimits?andwhatareestimatedtargetanalytelevelsforthefollowingtestparameters.1.3.1.1.1Estimatedsourceconcentrationfortotalchromiumand/orCr+6.1.3.1.1.2Estimatedminimumsamplingtimeand/orvolumerequiredtomeetmethoddetectionlimitrequirements(AppendixB40CFRPart136)formeasurementoftotalchromiumand/orCr+6.1.3.1.1.3DemonstratethatplannedsamplingparameterswillmeetDQOs.Theprotocolmustdemonstratethattheplannedsamplingparameterscalculatedbythetesterwillmeettheneedsofthesourceandtheenforcementauthority.1.3.1.2Thepre-testprotocolshouldincludeinformationonequipment,logistics,personnel,process2146operation,andotherresourcesnecessaryforanefficientandcoordinatedperformancetest.1.3.1.3Ataminimum,thepre-testprotocolshouldidentifyandbeapprovedbythesource,thetester,theanalyticallaboratory,andtheregulatoryenforcementauthority.Thetestershouldnotproceedwiththecompliancetestingbeforeobtainingapprovalfromtheenforcementauthority.2.0SummaryofMethod.2.1Sampling.2.1.1Anemissionsampleisextractedfromthesourceataconstantsamplingratedeterminedbyacriticalorificeandcollectedinasamplingtraincomposedofaprobeandimpingers.Theproportionalsamplingtimeatthecrosssectionaltraversepointsisvariedaccordingtothestackgasvelocityateachpoint.Thetotalsampletimemustbeatleasttwohours.2.1.2ThechromiumemissionconcentrationisdeterminedbythesameanalyticalproceduresdescribedinMethod306:inductively-coupledplasmaemissionspectrometry(ICP),graphitefurnaceatomicabsorptionspectrometry(GFAAS),orionchromatographywithapost-columnreactor(IC/PCR).21472.1.2.1Totalchromiumsampleswithhighchromiumconcentrations(35Fg/L)maybeanalyzedusinginductivelycoupledplasmaemissionspectrometry(ICP)at267.72nm.NOTE:TheICPanalysisisapplicableforthismethodonlywhenthesolutionanalyzedhasaCrconcentrationgreaterthanorequalto35Fg/LorfivetimesthemethoddetectionlimitasdeterminedaccordingtoAppendixBin40CFRPart136.2.1.2.2Alternatively,whenlowertotalchromiumconcentrations(35Fg/L)areencountered,aportionofthealkalinesamplesolutionmaybedigestedwithnitricacidandanalyzedbygraphitefurnaceatomicabsorptionspectroscopy(GFAAS)at357.9nm.2.1.2.3Ifitisdesirabletodeterminehexavalentchromium(Cr+6)emissions,thesamplesmaybeanalyzedusinganionchromatographequippedwithapost-columnreactor(IC/PCR)andavisiblewavelengthdetector.ToincreasesensitivityfortracelevelsofCr+6,apreconcentrationsystemmaybeusedinconjunctionwiththeIC/PCR.3.0Definitions.3.1TotalChromium-measuredchromiumcontentthatincludesbothmajorchromiumoxidationstates(Cr+3,Cr+6).3.2May-Impliesanoptionaloperation.21483.3Digestion-Theanalyticaloperationinvolvingthecomplete(ornearlycomplete)dissolutionofthesampleinordertoensurethecompletesolubilizationoftheelement(analyte)tobemeasured.3.4Interferences-Physical,chemical,orspectralphenomenathatmayproduceahighorlowbiasintheanalyticalresult.3.5AnalyticalSystem-Allcomponentsoftheanalyticalprocessincludingthesampledigestionandmeasurementapparatus.3.6SampleRecovery-Thequantitativetransferofsamplefromthecollectionapparatustothesamplepreparation(digestion,etc.)apparatus.Thistermshouldnotbeconfusedwithanalyticalrecovery.4.0Interferences.4.1SameasinMethod306,Section4.0.5.0Safety.5.1Disclaimer.Thismethodmayinvolvehazardousmaterials,operations,andequipment.Thistestmethoddoesnotpurporttoaddressallofthesafetyissuesassociatedwithitsuse.Itistheresponsibilityoftheusertoestablishappropriatesafetyandhealthpracticesandtodeterminetheapplicabilityofregulatorylimitationspriortoperformingthistestmethod.21495.2ChromiumandsomechromiumcompoundshavebeenlistedascarcinogensalthoughChromium(III)compoundsshowlittleornotoxicity.Chromiumisaskinandrespiratoryirritant.6.0EquipmentandSu