Designation:D5756−02(Reapproved2008)StandardTestMethodforMicrovacuumSamplingandIndirectAnalysisofDustbyTransmissionElectronMicroscopyforAsbestosMassSurfaceLoading1ThisstandardisissuedunderthefixeddesignationD5756;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversaprocedureto(a)identifyasbestosindustand(b)provideanestimateofthesurfaceloadingofasbestosinthesampleddust,reportedaseitherthemassofasbestosperunitareaofsampledsurfaceorasthemassofasbestospermassofsampleddust.1.1.1Ifanestimateofasbestosstructurecountsistobedetermined,theuserisreferredtoTestMethodD5755.1.2Thistestmethoddescribestheequipmentandproce-duresnecessaryforsampling,byamicrovacuumtechnique,non-airbornedustforlevelsofasbestos.Thenon-airbornesampleiscollectedinsideastandardfiltermembranecassettefromthesamplingofasurfaceareafordustwhichmaycontainasbestos.1.2.1Thisprocedureusesamicrovacuumingsamplingtech-nique.Thecollectionefficiencyofthistechniqueisunknown.Variabilityofcollectionefficiencyforanyparticularsubstrateandacrossdifferenttypesofsubstratesisalsounknown.Theeffectsofsamplingefficiencydifferencesandvariabilityontheinterpretationofdustsamplingmeasurementshavenotbeendetermined.1.3Asbestosidentifiedbytransmissionelectronmicroscopy(TEM)isbasedonmorphology,selectedareaelectrondiffrac-tion(SAED),andenergydispersiveX-rayanalysis(EDXA).Someinformationaboutstructuresizeisalsodetermined.1.4Thistestmethodisgenerallyapplicableforanestimateofthesurfaceloadingofasbestosstartingfromapproximately0.24pgofasbestospersquarecentimetre(assumingamini-mumfiberdimensionof0.5µmby0.025µm,see17.8),butwillvarywiththeanalyticalparametersnotedin17.8.1.4.1Theprocedureoutlinedinthistestmethodemploysanindirectsamplepreparationtechnique.Itisintendedtodisag-gregateanddisperseasbestosintofibrilsa...
