Designation:F2650−13AnAmericanNationalStandardStandardTerminologyRelatingtoImpactTestingofSportsSurfacesandEquipment1ThisstandardisissuedunderthefixeddesignationF2650;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisterminologycoverstermsrelatedtoimpacttestmethodsandimpactattenuationspecificationsofsportsequip-mentandsurfaces.1.2Thisterminologyisappropriateforuseinthedevelop-mentofstandardsthatdescribegravity-drivenimpacttestmethodsorspecifyimpactattenuationperformancecriteriaandwhichfallunderthejurisdictionofASTMCommitteeF08onSportsEquipmentandFacilities.1.3Thisterminologydefinescommontermsthatareappli-cabletomanysports-relatedimpacttestsincludingthoseusedinthecontextofsportssurfaces,athleticfootwear,protectiveequipmentandpadding.Theuseofacommonterminologywillpromotegreaterconsistencyamongstandardsandreducetheriskofmisinterpretation.1.4ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.2.Terminology2.1Definitions:acceleration,n—rateofchangeofvelocitywithtime.DISCUSSION—Accelerationisavectorquantity,havingbothmagni-tudeanddirection.Accelerationmagnitudeisexpressedinunitsofm/s−2(ft/s−2)anddirectionisdefinedrelativetoaCartesiancoordinatesystemorotherspatialreferenceframe.assistedimpacttest,n—animpacttestinwhichthemissileisacceleratedbymeansotherthangravityalone,forexample,byanactuator.dropheight(h),n—heightfromwhichamissileisdroppedduringagravity-drivenimpacttest,measuredastheverticaldistancebetweenthelowestpointoftheelevatedmissileanditsfirstpointofcontactwiththeimpactedsurfaceoranvil.theoreticaldropheight,n—dropheight(h)that,understandardconditions,wouldresultinanimpactvelocityequaltoamissile’smeasuredimpactvelocity(V0).DISCUSSION—The“standardconditions”assumestandardgravityandthatfr...
