Designation:E1194−17StandardTestMethodforVaporPressure1ThisstandardisissuedunderthefixeddesignationE1194;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethoddescribesproceduresformeasuringthevaporpressureofpureliquidorsolidcompounds.Nosingletechniqueisabletomeasurevaporpressuresfrom1×10−11to100kPa(approximately10−10to760torr).Thesubjectofthisstandardisgassaturationwhichiscapableofmeasuringvaporpressuresfrom1×10–11to1kPa(approximately10–10to10torr).Othermethods,suchasisoteniscopeanddifferentialscanningcalorimetry(DSC)aresuitableformeasuringvaporpressuresabove0.1kPaAnisoteniscope(standard)procedureformeasuringvaporpressuresofliquidsfrom1×10−1to100kPa(approximately1to760torr)isavailableinTestMethodD2879.ADSC(standard)procedureformeasuringvaporpressuresfrom2×10−1to100kPa(approximately1to760torr)isavailableinTestMethodE1782.Agas-saturationprocedureformeasuringvaporpressuresfrom1×10−11to1kPa(approximately10−10to10torr)ispresentedinthistestmethod.AllproceduresaresubjectsofU.S.EnvironmentalProtectionAgencyTestGuidelines.1.2Thegassaturationmethodisveryusefulforprovidingvaporpressuredataatnormalenvironmentaltemperatures(–40to+60°C).Atleastthreetemperaturevaluesshouldbestudiedtoallowdefinitionofavaporpressure-temperaturecorrelation.Valuesdeterminedshouldbebasedontemperatureselectionssuchthatameasurementismadeat25°C(asrecommendedbyIUPAC)(1),2avaluecanbeinterpolatedfor25°C,oravaluecanbereliablyextrapolatedfor25°C.Extrapolationto25°Cshouldbeavoidedifthetemperaturerangetestedincludesavalueatwhichaphasechangeoccurs.Extrapolationto25°Coverarangelargerthan10°Cshouldalsobeavoided.Ifpossible,thetemperaturesinvestigatedshouldbeaboveandbelow25°Ctoavoidextrapolationaltogether.Thegassatura-tionmethodwasselectedbecauseofitsextendedrange,sim...
