Designation:D6668−21StandardTestMethodforDiscriminationBetweenFlammabilityRatingsofF=0andF=11ThisstandardisissuedunderthefixeddesignationD6668;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoversameansforthediscriminationbetweensolidandliquidmaterialswhichwillnotburninairwhenexposedtoatemperatureof1500°F(815.5°C)foraperiodof5minandthosewhichwilligniteandburnunderthesameconditions.1.2Thistestmethodmaybeappliedtoanysubstancewhichisasolidorliquidatambienttemperatureandpressure.1.3Thepurposeofthistestmethodistoprovideameansfortheclassificationoftheflammabilityhazardofmaterialsofhazarddegrees(F=0)and(F=1)orboth,inaccordancewiththedefinitionsofdegreesofflammabilityhazardasdefinedbyNFPA704(par.3.2.1).1.4Thistestmethodshouldbeusedsubjecttothelimita-tionsthatnosinglefirehazardpropertysuchasflashpoint,ignitiontemperature,ortheperformanceundertheconditionsofthepresentmethodshallbeusedtodescribeorappraisethefirehazardorfireriskofamaterial,product,assemblyorsystemunderactualfireconditions.Firehazardpropertiesmeasuredundercontrolledlaboratoryconditionsmay,nevertheless,beemployedtodescribeproperlytheresponseofmaterials,products,assembliesorsystemsundersaidcon-trolledconditions.Propertiesmeasuredundercontrolledlabo-ratoryconditionsmaybeusedaselementsofhazardorriskassessmentonlywhensuchassessmenttakesintoaccountallofthefactorsthatarepertinenttotheevolutionofthefirehazardofagivensituation.1.5Thevaluesstatedininch-poundunitsaretoberegardedasstandard.ThevaluesgiveninparenthesesaremathematicalconversionstoSIunitsthatareprovidedforinformationonlyandarenotconsideredstandard.1.6Thisstandardisusedtopredictorprovideaquantitativemeasureofthefirehazardfromaspecifiedsetoffireconditionsinvolvingspecificmaterials,products,orassemblies.Thisassessmentdoesnotnec...
