Designation:D2743–68(Reapproved1998)StandardPracticesforUniformityofTrafficPaintVehicleSolidsbySpectroscopyandGasChromatography1ThisstandardisissuedunderthefixeddesignationD2743;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thesepracticesprovidegeneralinformationontheinstrumentaltechniquesavailablefordetectingadulterationornonuniformityofthechemicalnatureofthevehiclesolidsinpurchasedlotsoftrafficpaintsbymeansoftheindividualorcombineduseofinfraredandultravioletspectroscopyandgaschromatography.Theproceduresgivenareapplicablewhentrafficpaintisselectedandpurchasedonthebasisofpre-qualificationlaboratoryorroadperformancetests,orboth,andareferencesampleoftheoriginalpaintsoevaluatedandselectedisretainedandcomparedwithtestsamplesrepresen-tativeofsubsequentpurchasedanddeliveredlotsofsuchpaintandwhicharerequiredtobethesameastheoriginalreferencesample.1.2Althoughnotspecificallyprovidedforintheseprac-tices,themethodsgivenmayalsobeapplied,withappropriatemodification,toevaluatingtheacceptabilityoftrafficpaintsthathavebeenpurchasedonthebasisofcompositionspecifi-cations.Insuchcases,applicationislimitedtothevehiclesolidsasbefore,aswellastheavailabilityofasuitablestandardorrangeofstandardsrepresentativeofthevehiclesolidsthatareacceptableandwithwhichsamplesofsubse-quentdeliveredlotswillbecompared.1.3Thetechniquesprovidedarewhollyadequatefordetect-inggrossadulterationofthevehiclesolidswherecompletelydifferentdryingoils,resins,orpolymers,orcombinationsofthesehavebeensubstitutedforthoseoriginallycontainedinthereferencesample.Incasesoflesseradulterationormodifica-tion,thesemethodshavebeenfoundadequatefordetectingvehiclesolids,adulterations,ormodificationsaslowas5weight%ofthevehiclesolids.1.4Thesetechniqueshavebeendevelopedonthebasisofcooperativeworkwithalkyd,chlorinated...
