Designation:D3456−18StandardPracticeforDeterminingbyExteriorExposureTeststheSusceptibilityofPaintFilmstoMicrobiologicalAttack1ThisstandardisissuedunderthefixeddesignationD3456;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticeprovidesguidelinesfordeterminingthesusceptibilityofpaintfilmstomicrobiologicalattackonexteriorexposure.Whileitisrecognizedthatvariousorgan-ismsmayoccuronanexposedcoating,thespecifictypesoforganismsaremainlyofacademicinterest.Thedegreetowhichmicrobiologicaldiscolorationoccursistheprimaryconcern.1.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D1006PracticeforConductingExteriorExposureTestsofPaintsonWoodD1849TestMethodforPackageStabilityofPaintD3274TestMethodforEvaluatingDegreeofSurfaceDis-figurementofPaintFilmsbyFungalorAlgalGrowth,orSoilandDirtAccumulationD6132TestMethodforNondestructiveMeasurementofDryFilmThicknessofAppliedOrganicCoatingsUsinganUltrasonicCoatingThicknessGageD7091PracticeforNondestructiveMeasurementofDryFilmThicknessofNonmagneticCoatingsAppliedtoFerrousMetalsandNonmagnetic,NonconductiveCoat-ingsAppliedtoNon-FerrousMetals3.SummaryofPractice3.1Simpleobservationofacoatedobjects...
