Designation:D7990−21AnAmericanNationalStandardStandardTestMethodforUsingReflectanceSpectratoProduceanIndexofTemperatureRiseinPolymericSiding1ThisstandardisissuedunderthefixeddesignationD7990;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodusesreflectancespectrafromtheultraviolet,visible,andnearinfraredregiontoproduceanindexofthetemperatureriseofpolymericsidingaboveambienttemperaturethatoccursduetoabsorptionofthesun’senergy.1.2Thetestmethoddeterminestheintensityfactorofasamplecolor.Theintensityfactorisafunctionofthesample’sreflectancespectraandtheenergyoutputoftheheatlampusedinthetestmethodTestMethodD4803.1.3AppendixX1providesamethodforusingtheintensityfactortodeterminethemaximumtemperatureriseofasampleunderseveresolarexposure.1.3.1Acorrelationbetweenintensityfactorandheatbuildup(temperaturerise)aspredictedbyTestMethodD4803exists.1.3.2Theheatbuildup(temperaturerise)forapolymericbuildingproductspecimenisdeterminedfromitsreflectancespectraandthecorrelation’sregressionequation.1.4Units—ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.6Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:D2244PracticeforCalculationofColorTolerancesandColorDifferencesfromInstrumentall...
