Designation:E2535−07(Reapproved2013)StandardGuideforHandlingUnboundEngineeredNanoscaleParticlesinOccupationalSettings1ThisstandardisissuedunderthefixeddesignationE2535;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.INTRODUCTIONNanometre-scaleparticlesareencounteredinnatureandinindustryinavarietyofformsandmaterials.Engineerednanoscaleparticlesasaclasscomprisearangeofmaterialsdifferinginshape,size,andchemicalcomposition,andrepresentabroadrangeofphysicalandchemicalproperties.Workerswithinsomenanotechnology-relatedindustriesandoperationshavethepotentialtobeexposedtotheseengineerednanoscaleparticlesatlevelsexceedingambientnanoscaleparticleconcentrationsthroughinhalation,dermalcontactandingestionwhennotcontainedonorwithinamatrix(unbound).Occupationalhealthrisksassociatedwithmanufacturing,processingandhandlingunboundnanoscaleparticles,agglomeratesoraggregatesofnanoscaleparticlesarenotyetclearlyunderstood.Dominantexposureroutes,potentialexposurelevelsandanymaterialhazardareexpectedtovarywidelyamongparticularnanoscaleparticlematerialsandhandlingcontexts.Additionalresearchisneededtounderstandtheimpactoftheseexposuresonemployeehealthandhowbesttodeviseappropriateexposuremonitoringandcontrolstrategies.Untilclearerunderstandingsemerge,thelimitedevidenceavailablesuggestscautionwhenpotentialexposurestounboundengineerednanoscaleparticles(UNP)mayoccur.1.Scope1.1Thisguidedescribesactionsthatcouldbetakenbytheusertominimizehumanexposurestounbound,engineerednanoscaleparticles(UNP)inresearch,manufacturing,labora-toryandotheroccupationalsettingswhereUNPmayreason-ablybeexpectedtobepresent.Itisintendedtoprovideguidanceforcontrollingsuchexposuresasacautionarymea-surewhereneitherrelevantexposurestandardsnordefinitivehazardandexposureinformationexist.1.2GeneralGuidance—Thisguideisapp...
