ASTMDLb43bOm075753000225752mfJ-04-904CTbDesignation:D1643-60(Reapproved1988)StandardTestMethodsfor~GasCheckingandDraftTestofVarnishFilms'ThisstandardisissuedunderthefixeddesignationD1643;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(0indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforirsebyagenciesoftheDepartmentofDefensetoreplaceMethods4161,4162,4171ofFederaiTestMethodStandardNo.141.ConsirlttheDoDIndexofSpecijicaiionsandStandardsforthespecificyearofissuewhichhasbeenadoptedbyiheDepartmentofDefense.1.Scope1.1Thesetestmethodscoverthedeterminationofthegascheckinganddrafttestofvarnishfilms.1.2Thisstandardmayinvolvehazardousmaterials,oper-ations,andequipment.Thisstandarddoesnotpurporttoaddressallofthesafetyproblemsassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.2.ReferencedDocument2.1ASTMStandard:D1640TestMethodsforDrying,Curing,orFilmForma-tionofOrganicCoatingsatRoomTemperatme'GASCHECKING3.Scope3.lThistestmethod3coverstwoalternativeproceduresfordetectingnonuniformappearancethatmaydevelopwhileafilmofvarnishdriesinanatmospherethathasbeenfouledbyproductsofcombustion.Thenonuniformappear-anceisgenerallyrelatedtowrinkling,whichissometimesmicroscopicandwhichisvariouslydescribedaschecking,crow's-footing,crystallization,ordulling.Appearancenon-uniformitiesthatdevelopondriedfilmsandaredescribedbysuchtermsasorange-peel,haze,silking,flooding,etc.,arenotwithinthescopeofthistestmethod.4.SummaryofTestMethod4.1Thevarnishfilmundertestisexposedtofoulgasforvariousperiodsbeforethefilmhasbeenconvertedfromliquidtosubstantiallysolid,sincethefoulgasiseffective,withinthescopeofthesetestmethods,only,beforethevarnishfilmhasbecomeset-to-touchordust-free.PROCEDUREA-BELLJARTEST5.Apparatus5....
