Designation:G177−03(Reapproved2012)StandardTablesforReferenceSolarUltravioletSpectralDistributions:Hemisphericalon37°TiltedSurface1ThisstandardisissuedunderthefixeddesignationG177;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ε1NOTE—ThetitletoTable2wascorrectededitoriallyinAugust2008.INTRODUCTIONThesetablesofsolarultraviolet(UV)spectralirradiancevalueshavebeendevelopedtomeettheneedforastandardultravioletreferencespectralenergydistributiontobeusedasareferencefortheupperlimitofultravioletradiationintheoutdoorweatheringofmaterialsandrelatedindoorexposurestudies.Awidevarietyofsolarspectralenergydistributionsoccurinthenaturalenvironmentandaresimulatedbyartificialsourcesduringproduct,material,orcomponenttesting.Tocomparetherelativeopticalperformanceofspectrallysensitiveproducts,ortocomparetheperformanceofproductsbeforeandafterbeingsubjectedtoweatheringorotherexposureconditions,areferencestandardsolarspectraldistributionisrequired.Thesetableswerepreparedusingversion2.9.2oftheSimpleModeloftheAtmosphericRadiativeTransferofSunshine(SMARTS2)atmospherictransmissioncode(1,2).2SMARTS2usesempiricalparameterizationsofversion4.0oftheAirForceGeophysicalLaboratory(AFGL)ModerateResolutionTransmissionmodel,MODTRAN(3,4).AnextraterrestrialspectrumdifferingonlyslightlyfromtheextraterrestrialspectruminASTME490isusedtocalculatetheresultantspectra.Thehemispherical(2πsteradianacceptanceangle)spectralirradianceonapaneltilted37°(averagelatitudeofthecontiguousUnitedStates)tothehorizontalistabulated.Thewavelengthrangeforthespectraextendsfrom280to400nm,withuniformwavelengthintervals.TheinputparametersusedinconjunctionwithSMARTS2foreachsetofconditionsaretabulated.TheSMARTS2modelanddocumentationareavailableasanadjunctADJG173CD3)tothisstandard.1.Scope1.1Thetableprovidesastandardultravi...
