Designation:F2657−07(Reapproved2018)StandardTestMethodforOutdoorWeatheringExposureofCrosslinkedPolyethylene(PEX)Tubing1ThisstandardisissuedunderthefixeddesignationF2657;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethoddescribestheprocedureforexposingcrosslinkedpolyethylene(PEX)tubingproducedinaccordancewithSpecificationF876tonatural(sunlight)ultraviolet(UV)radiationandevaluatingtheeffectsoftheexposure.Thistestmethodoutlinestherequirementsforspecimensizeandpreparation,exposureorientation,minimumUVexposureenergy,postexposuretestingandreporting.NOTE1—WhileotherlaboratoryUVexposuresystemsareavailable,thistestmethodreliesonnaturalsunlightastheUVradiationsource.Laboratorymethodsmaybeaddedinthefutureiftestingconfirmsacorrelationbetweennaturalsunlightandlaboratoryexposure.1.2PEXtubingisnotdesignedforoutdooruse.Datafromshort-termexposuretestingperthistestmethodcanbeusedtojudgetherelativeperformanceofPEXtubingstoredoutdoorsforshortperiodsoftimepriortoinstallationcompletelyshieldedfromsunlight.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thefollowingprecautionarycaveatpertainsonlytothetestmethodandpostexposuretestingportions,Sections8and9ofthistestmethod.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafety,health,andenvironmentalpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2....
