Designation:D3880/D3880M−90(Reapproved2017)StandardTestMethodforAsbestosStrengthUnits1ThisstandardisissuedunderthefixeddesignationD3880/D3880M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodgivesaprocedurefortheevaluationofthestrength-givingpropertiesofasbestosfibersusedtorein-forceasbestos-cementproducts.1.2Thepurposeofthistestmethodistodeterminethenumberofstrengthunitsthatmaybeassignedtothesampletested.1.3Asbestosfiberpossessestheabilitytoimpartstrengthtoanasbestos-cementproduct.Everyfibergrademayberegardedaspossessingacertainquantityofstrength-givingunits.Thequantityoffiberrequiredinanasbestos-cementcompositionvariesinverselywiththenumberofstrengthunitsitpossesses.Forexample,ifanamount,designatedbyX,ofafiberpossessing100strengthunitsproducesaproductofagivenstrength,2Xwouldberequiredtoproduceaproductofequivalentstrengthfromfiberpossessingonly50strengthunits.1.4Thefollowingdefinitionisthebasisforthestrengthunittest:Anasbestosfiberthatgivesthestandardstrengthatthestandarddensitywhenusedas10%ofthefurnishisdefinedashaving100strengthunits.Therefore,byknowingthepercentfiberrequiredinthemixtogivestandardstrengthatthestandarddensity,itispossibletocalculatethestrengthunitsofasampleofasbestos.1.5Thisprocedureisintendedprimarilyforchrysotileasbestos;ithasnotbeenverifiedwhetherornotitisapplicabletoothertypes.1.6ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.1.7Warning—Breathingofasbestosdustishazardous.Asbestosandasbestosproductspresentdemonstratedhealthrisksforusersandforthosewithwhomtheycomeintocontact.Inadditiontootherprecaut...
