Designation:F959−15StandardSpecificationforCompressible-Washer-TypeDirectTensionIndicatorsforUsewithStructuralFasteners1ThisstandardisissuedunderthefixeddesignationF959;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thisspecificationcoverstherequirementsforcompressible-washer-typedirecttensionindicators,(DTIs)capableofindicatingtheachievementofaspecifiedminimumbolttensioninastructuralbolt.1.2EighttypesofDTIsinnominaldiametersizes1⁄2through11⁄2in.aswellasM16throughM36arecovered:1.2.1Type325-1—DTIsforusewithSpecificationA325Type1boltsorForF1852assemblies.1.2.2Type325–3—DTIsforusewithSpecificationA325Type3boltsorF1852Type3assemblies.1.2.3Type490–1—DTIsforusewithSpecificationA490Type1boltsorF2280assemblies.1.2.4Type490–3—DTIsforusewithSpecificationA490Type3F2280Type3assemblies.1.2.5Type8.8-1—DTIsforusewithSpecificationA325MType1bolts.1.2.6Type8.8-3—DTIsforusewithSpecificationA325MType3bolts.1.2.7Type10.9-1—DTIsforusewithSpecificationA490MType1bolts.1.2.8Type10.9-3—DTIsforusewithSpecificationA490MType3bolts.1.3DTIsareintendedforinstallationundereitheraboltheadorahardenedwasher.(SeeResearchCouncilonStruc-turalConnections:SpecificationforStructuralJointsUsingHigh–StrengthBolts.)1.4ThisspecificationprovidesforfurnishingType3DTIstoaChemicalCompositionRequirementoraCorrosionResistanceIndex(CRI)atthemanufacturer’sdiscretion.1.5TermsusedinthisspecificationaredefinedinTermi-nologyF1789unlessotherwisespecified.1.6Thefollowingprecautionarystatementpertainsonlytothetestmethodportions,Section10andAppendixX1ofthisspecification:Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitati...
