Designation:D2240−05(Reapproved2010)StandardTestMethodforRubberProperty—DurometerHardness1ThisstandardisissuedunderthefixeddesignationD2240;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thistestmethodcoverstwelvetypesofrubberhardnessmeasurementdevicesknownasdurometers:TypesA,B,C,D,DO,E,M,O,OO,OOO,OOO-S,andR.Theprocedurefordeterminingindentationhardnessofsubstancesclassifiedasthermoplasticelastomers,vulcanized(thermoset)rubber,elas-tomericmaterials,cellularmaterials,gel-likematerials,andsomeplasticsisalsodescribed.1.2Thistestmethodisnotequivalenttootherindentationhardnessmethodsandinstrumenttypes,specificallythosedescribedinTestMethodD1415.1.3Thistestmethodisnotapplicabletothetestingofcoatedfabrics.1.4Allmaterials,instruments,orequipmentusedforthedeterminationofmass,force,ordimensionshallhavetrace-abilitytotheNationalInstituteforStandardsandTechnology,orotherinternationallyrecognizedorganizationsparallelinnature.1.5ThevaluesstatedinSIunitsaretoberegardedasstandard.Thevaluesgiveninparenthesesareforinformationonly.ManyofthestateddimensionsinSIaredirectconver-sionsfromtheU.S.CustomarySystemtoaccommodatetheinstrumentation,practices,andproceduresthatexistedpriortotheMetricConversionActof1975.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D374TestMethodsforThicknessofSolidElectricalInsu-lation(Withdrawn2013)3D618PracticeforConditioningPlasticsforTestingD785TestMethodforRockwellHardnessofPlasticsandElectricalInsulatingMaterialsD1349PracticeforRubber—Stand...