Designation:D56−22StandardTestMethodforFlashPointbyTagClosedCupTester1ThisstandardisissuedunderthefixeddesignationD56;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.INTRODUCTIONThisdynamicflashpointtestmethodemploysaprescribedrateoftemperatureriseforthematerialundertest.Therateofheatingmaynotinallcasesgivetheprecisionquotedinthetestmethodbecauseofthelowthermalconductivityofcertainmaterials.Toimprovethepredictionofflammability,TestMethodD3941,whichutilizesaslowerheatingrate,wasdeveloped.TestMethodD3941providesconditionsclosertoequilibriumwherethevaporabovetheliquidandtheliquidareataboutthesametemperature.IfaspecificationrequiresTestMethodD56,donotchangetoTestMethodD3941orothertestmethodwithoutpermissionfromthespecifier.Flashpointvaluesareafunctionoftheapparatusdesign,theconditionoftheapparatusused,andtheoperationalprocedurecarriedout.Flashpointcanthereforeonlybedefinedintermsofastandardtestmethod,andnogeneralvalidcorrelationcanbeguaranteedbetweenresultsobtainedbydifferenttestmethods,orwithtestapparatusdifferentfromthatspecified.1.Scope*1.1Thistestmethodcoversthedeterminationoftheflashpoint,byTagmanualandautomatedclosedtesters,ofliquidswithaviscositybelow5.5mm2/s(cSt)at40°C(104°F),orbelow9.5mm2/s(cSt)at25°C(77°F),andaflashpointbelow93°C(200°F).1.1.1Twosetsoftestconditionsareusedwithinthistestmethod:lowtemperature(LT)testconditionsforexpectedflashpoints<60°C,andhightemperature(HT)testconditionsforexpectedflashpointsof≥60°C.1.1.2Fortheclosed-cupflashpointofliquidswiththefollowingproperties:aviscosityof5.5mm2/s(cSt)ormoreat40°C(104°F);aviscosityof9.5mm2/s(cSt)ormoreat25°C(77°F);aflashpointof93°C(200°F)orhigher;atendencytoformasurfacefilmundertestconditions;orcontainingsuspend...
