Designation:D6556−21StandardTestMethodforCarbonBlack—TotalandExternalSurfaceAreabyNitrogenAdsorption1ThisstandardisissuedunderthefixeddesignationD6556;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1ThistestmethodcoversthedeterminationofthetotalsurfaceareabytheBrunauer,Emmett,andTeller(B.E.T.NSA)theoryofmultilayergasadsorptionbehaviorusingmultipointdeterminationsandtheexternalsurfaceareabasedonthestatisticalthicknesssurfaceareamethod.1.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.(Theminimumsafetyequipmentshouldincludeprotectivegloves,sturdyeyeandfaceprotection).1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D1799PracticeforCarbonBlack—SamplingPackagedShipmentsD1900PracticeforCarbonBlack—SamplingBulkShip-mentsD3765TestMethodforCarbonBlack—CTAB(Cetyltrim-ethylammoniumBromide)SurfaceArea(Withdrawn2007)3D4483PracticeforEvaluatingPrecisionforTestMethodStandardsintheRubberandCarbonBlackManufacturingIndustries3.SummaryofTestMethod3.1Thetotalandexternalsurfaceareasaremeasuredbyevaluatingtheamountofnitrogenadsorbed,atliquidnitrogentemperature,byacarbonblackatseveralpartialpressuresofnitrogen.TheadsorptiondataisusedtocalculatetheNSAandSTSAvalues.4.SignificanceandUse4.1Thi...
