Designation:D6539−13StandardTestMethodforMeasurementofthePermeabilityofUnsaturatedPorousMaterialsbyFlowingAir1ThisstandardisissuedunderthefixeddesignationD6539;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoverslaboratorydeterminationofthecoefficientofpermeabilityfortheflowofairthroughunsatu-ratedporousmaterials.1.2Thistestmethodmaybeusedwithintactorcompactedcoarsegrainedsoils,silts,orleancohesivesoilsthathavealowdegreeofsaturationandthathavepermeabilitybetween1.0×10-15m2(1.01millidarcy)and1.0×10-10m2(101darcy).1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.1.3.1BytraditioninU.S.practice,thepermeabilityofporousmediaisreportedinunitsofdarcy,althoughtheSIunitforpermeabilityism2.1.4AllobservedandcalculatedvaluesshallconformtotheguidelinesforsignificantdigitsandroundingestablishedinPracticeD6026.1.4.1Forthepurposeofcomparingameasuredorcalcu-latedvaluewithspecifiedlimits,themeasuredorcalculatedvalueshallberoundedtothesameprecisionasthespecifiedlimits.1.4.2Theproceduresusedtospecifyhowdataarecollected/recordedorcalculated,inthisstandardareregardedastheindustrystandard.Inaddition,theyarerepresentativeofthesignificantdigitsthatgenerallyshouldberetained.Theproce-duresuseddonotconsidermaterialvariation,purposeforobtainingthedata,specialpurposestudies,oranyconsider-ationsfortheuser’sobjectives;anditiscommonpracticetoincreaseorreducesignificantdigitsofreporteddatatobecommensuratewiththeseconsiderations.Itisbeyondthescopeofthisstandardtoconsidersignificantdigitsusedinanalysismethodsforengineeringdesign.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationsprior...
