Designation:D4590−13StandardTestMethodforColorimetricDeterminationofp-tert-ButylcatecholInStyreneMonomerorAMS(α–Methylstyrene)bySpectrophotometry1ThisstandardisissuedunderthefixeddesignationD4590;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodisapplicabletothedeterminationofresidual4-tertiary-butylcatechol(TBC)instyrenemonomerorAMSinthe1to100mg/kgrange.Anyothercompoundproducingcolorat490nmwhencontactedwithaqueoussodiumhydroxidesolutionwillinterfere.Itmaybecompen-satedforbyincludingitinthepreparationofthestandardsolutions,ifitsidentityandconcentrationinthesampleareknown.1.2Indeterminingtheconformanceofthetestresultsusingthismethodtoapplicablespecifications,resultsshallberoundedoffinaccordancewiththerounding-offmethodofPracticeE29.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.Forspecificstatementsonhazards,seeSection8.2.ReferencedDocuments2.1ASTMStandards:2D1193SpecificationforReagentWaterD3437PracticeforSamplingandHandlingLiquidCyclicProductsD4790TerminologyofAromaticHydrocarbonsandRelatedChemicalsD6809GuideforQualityControlandQualityAssuranceProceduresforAromaticHydrocarbonsandRelatedMa-terialsE29PracticeforUsingSignificantDigitsinTestDatatoDetermineConformancewithSpecificationsE691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethod2.2OtherDocument:OSHARegulations,29CFRparagraphs1910.1000and1910.120033.Terminology3.1SeeTerminologyD4790fordefinitionoftermsusedinthisstandard.4.SummaryofMethod4.1Colorisdevelope...
