Designation:D7869−17StandardPracticeforXenonArcExposureTestwithEnhancedLightandWaterExposureforTransportationCoatings1ThisstandardisissuedunderthefixeddesignationD7869;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticespecifiestheoperatingproceduresforacontrolledirradiancexenonarclightandwaterapparatus.Theprocedureusesoneormorelamp(s)andopticalfilter(s)toproduceirradiancesimilartosunlightintheUVandvisiblerange.Italsosimulatesthewaterabsorptionandstresscyclesexperiencedbyautomotiveexteriorcoatingsundernaturalweatheringconditions.Thispracticehasalsobeenfoundapplicabletocoatingsonothertransportationvehicles,suchasaircraft,trucksandrailcars.1.2Thispracticeusesaxenonarclightsourcewithspeci-fiedopticalfilter(s).Thespectralpowerdistribution(SPD)forthelampandspecialdaylightfilter(s)isasspecifiedinAnnexA1.Theirradiancelevelusedinthispracticevariesbetween0.40and0.80W/(m2·nm)at340nm.Waterissprayedonthespecimensduringportionsofseveraldarksteps.Theapplica-tionofwaterissuchthatthecoatingswillabsorbanddesorbsubstantialamountsofwaterduringtesting.Inaddition,thecyclingbetweenwet/dryandwarm/coolwillinducemechani-calstressesintothematerials.Thesetestconditionsaredesignedtosimulatethephysicalandchemicalstressesfromenvironmentsinasubtropicalclimate,suchassouthernFlorida.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D4517TestMethodforLow-LevelTotalSilicainHigh-PurityWaterbyFlamelessAtomicAbsorptionSpectros-copyG113Terminology...
