Designation:E1294–89(Reapproved1999)StandardTestMethodforPoreSizeCharacteristicsofMembraneFiltersUsingAutomatedLiquidPorosimeter1ThisstandardisissuedunderthefixeddesignationE1294;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethoddescribesaprocedureformeasuringtheporesizecharacteristicsofmembranefiltersintherangeofapproximately0.05to300µm.1.2ThistestmethodusestheautomatedbubblepointmethoddescribedinASTMTestMethodF316.1.3TheliquiddisplacementtechniqueusedinthistestmethoddependsuponthecapillaryrisecreatedbysurfacetensionandusestheWashburnequationforcalculatingtheporediameter.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:F316TestMethodforPoreSizeCharacteristicsofMem-braneFiltersforUsewithAerospaceFluids23.SummaryofTestMethod3.1Afilterwetwithliquidexhibitspropertiessimilartothoseofarrayofliquidfilledcapillaries(seeNote).Thesampleundertestisthoroughlywettedwithliquidoflowsurfacetensionandlowvaporpressureandplacedinasampleholderassembly.Anincreasingairpressureisappliedupstreamofthesampleandassuccessivelysmallerporesempty,theairflowacrossthesampleisrecordedasafunctionofappliedpressure.Thepointoffirstflowisidentifiedasthebubblepoint(maximumporesize).Thiscontinuesuntilthesmallestdetect-ableporeisreached.Thisinformationisthencomparedwiththeflowrateagainstappliedpressureresponseforthedrysample.Theporesizedistributionisthenobtainedfromwetanddrycurves.NOTE1—Thistestmethodwillnotchangetheprioritiesofthemembraneifthetestliquidsarechosentobecompatiblewiththematerialfromwhichitismade.4.SignificanceandUse4.1Thistestmethodma...
