Designation:G178−09StandardPracticeforDeterminingtheActivationSpectrumofaMaterial(WavelengthSensitivitytoanExposureSource)UsingtheSharpCut-OnFilterorSpectrographicTechnique1ThisstandardisissuedunderthefixeddesignationG178;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticedescribesthedeterminationoftherelativeactiniceffectsofindividualspectralbandsofanexposuresourceonamaterial.Theactivationspectrumisspecifictothelightsourcetowhichthematerialisexposedtoobtaintheactivationspectrum.Alightsourcewithadifferentspectralpowerdistributionwillproduceadifferentactivationspectrum.1.2Thispracticedescribestwoproceduresfordetermininganactivationspectrum.Oneusessharpcut-onUV/visibletransmittingfiltersandtheotherusesaspectrographtodeterminetherelativedegradationcausedbyindividualspec-tralregions.NOTE1—Othertechniquescanbeusedtoisolatetheeffectsofindividualspectralbandsofalightsource,forexample,interferencefilters.1.3Thetechniquesareapplicabletodeterminationofthespectraleffectsofsolarradiationandlaboratoryacceleratedtestdevicesonamaterial.TheyaredescribedfortheUVregion,butcanbeextendedintothevisibleregionusingdifferentcut-onfiltersandappropriatespectrographs.1.4Thetechniquesareapplicabletoavarietyofmaterials,bothtransparentandopaque,includingplastics,paints,inks,textilesandothers.1.5Theopticaland/orphysicalpropertychangesinamaterialcanbedeterminedbyvariousappropriatemethods.Themethodsofevaluationarebeyondthescopeofthispractice.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.NOTE2—ThereisnoISOstandardthatisequivalenttothisstandard.2.ReferencedDocuments2.1ASTMStanda...
