Designation:D5870−22StandardPracticeforCalculatingPropertyRetentionIndexofPlastics1ThisstandardisissuedunderthefixeddesignationD5870;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thispracticecoversproceduresforthecalculationofapropertyretentionindex(PRI)ofthermoplasticandthermosetplasticsafterexposuretothermalaging,naturalorartificialacceleratedweathering,orchemicalexposures.1.2Thispracticeisnotintendedtoestablishafixedproce-dureforconductingtheexposuretest,butitisintendedtoprovideasetofspecificproceduresusedtocalculatetheretentionindexofacharacteristicpropertyofthematerialafterithasbeenexposed.Selectionofthespecificexposuretestconditionsdependsonthematerialbeingtestedandthepropertybeingmeasured.Itisuptotheusertodeterminewhichexposuretestconditionsaremostrelevanttothespecificmaterialandtheserviceconditionbeingused.Theexposuretestusedmustbeconductedinaccordancewithconditionsdescribedinspecificexposurestandards.1.3Thispracticedoesnotdescribeproceduresforsamplingthematerialstobetested.Theseproceduresaredescribedinthestandardsandspecificationsapplicabletothematerialbeingevaluated.1.4TheprocedureusedtocalculatethePRIdependsonwhetherthetestusedtocharacterizethematerialsbeingexposedisdestructiveornondestructive.ThePRIcanbeusefulindescribingshort-termmechanical,electrical,andotherpropertiesofplasticsatspecifiedtemperaturesafterthemate-rialshavebeensubjectedtoanexposuretest.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.NOTE1—ThereisnosimilarorequivalentISOstandard.ISO11248issignificantlydifferentsinceitpertainsonlytothermosettingresins.1.6Thisin...
