Designation:C91/C91M−12StandardSpecificationforMasonryCement1ThisstandardisissuedunderthefixeddesignationC91/C91M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thisspecificationcoversthreetypesofmasonrycementforusewheremortarformasonryisrequired.1.2Units—ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.ValuesinSIunitsshallbeobtainedbymeasurementinSIunitsorbyappropriateconversion,usingtheRulesforConversionandRoundinggiveninStandardIEEE/ASTMSI10,ofmeasurementsmadeinotherunits.ValuesarestatedinonlySIunitswheninch-poundunitsarenotusedinpractice.1.3Thetextofthisstandardreferstonotesandfootnoteswhichprovideexplanatorymaterial.Thesenotesandfootnotes(excludingthoseintablesandfigures)shallnotbeconsideredasrequirementsofthestandard.1.4ThefollowingsafetyhazardscaveatpertainsonlytoSections16and17ofthisspecification.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.(Warning—Freshhydrauliccementitiousmixturesarecausticandmaycausechemicalburnstoskinandtissueuponprolongedexposure.)22.ReferencedDocuments2.1ASTMStandards:3C109/C109MTestMethodforCompressiveStrengthofHydraulicCementMortars(Using2-in.or[50-mm]CubeSpecimens)C151TestMethodforAutoclaveExpansionofHydraulicCementC183PracticeforSamplingandtheAmountofTestingofHydraulicCementC185TestMethodforAirContentofHydraulicCementMortarC187TestMethodforAmo...
