ASTM_F_1957_-_99_2011.pdf

Designation:F195799(Reapproved 2011)Standard Test Method forComposite Foam Hardness-Durometer Hardness1This standard is issued under the fixed designation F1957;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method describes a type of composite foamhardness measurement device known as durometer:Type CF.The procedure for determining indentation hardness of sub-stances comprised of two or more elastomeric materials,one ofwhich is a foam or foam like material.These are classified ascomposite foam structures.The composite foam product mayhave an armature made of a material suitable for addingstructural integrity including but not limited to metal,plastic,or wood.This construction is typical for lapbar restraints,seating,and other restraint devices,as well as some showelements.1.2 This test method is not equivalent to other indentationhardness methods and instrument types,specifically thosedescribed in Test Methods D1415 and D2240.1.3 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.Many of the stated dimensions in SI are direct conver-sions from the U.S.customary system to accommodate theinstrumentation,practices,and procedures that existed prior tothe Metric Conversion Act of 1975.1.4 All materials,instruments,or equipment used for thedetermination of mass or dimension shall have traceability tothe National Institute for Standards and Technology(NIST)orother internationally recognized organizations.1.5 This test method is not a safety standard as it pertains toride legislation.The use of this test method is optional basedupon an agreement between customers and suppliers of foamproducts.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D374 Test Methods for Thickness of Solid Electrical Insu-lation(Withdrawn 2013)3D618 Practice for Conditioning Plastics for TestingD785 Test Method for Rockwell Hardness of Plastics andElectrical Insulating MaterialsD1349 Practice for RubberStandard Conditions for Test-ingD1415 Test Method for Rubber PropertyInternationalHardnessD2240 Test Method for Rubber PropertyDurometer Hard-nessD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustries3.Summary of Test Method3.1 This test method permits hardness measurements basedon either initial indentation or indentation after a specifiedperiod of time,or both.3.2 Those specimens,which have a durometer hardnessrange other than specified,shall use another suitable procedurefor determining durometer hardness.4.Significance and Use4.1 This test method is based on the penetration by aspecific type of indentor when forced into the material underspecified conditions.The indentation hardness is related in-versely to the penetration and is dependent on the elasticmodulus and viscoelastic behavior of the material.The geom-etry of the indentor and the applied force influence themeasurements,such that no simple relationship exists betweenthe measurements obtained with one type of durometer andthose obtained with another type of durometer or otherinstruments used for measuring hardness.This test method isan empirical test intended primarily for control purposes.No1This test method is under the jurisdiction of ASTM Committee F24 onAmusement Rides and Devicesand is the direct responsibility of F24.10 on TestMethods.Current edition approved Jan.15,2011.Published June 2011.Originallyapproved in 1999.Last previous edition approved in 2004 as F1957 99(2004).DOI:10.1520/F1957-99R11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 simple relationship exists between indentation hardness deter-mined by this test method and any fundamental property of thematerial tested.For specification purposes it is recommendedthat Test Method D785 be used for hard materials and TestMethod D2240 be used for solid elatomers.5.Apparatus5.1 Hardness measurement apparatus,or durometer,consist-ing of the following components:5.1.1 Presser Foot,with an orifice(to allow for the protru-sion of the indentor)having a diameter as specified in Fig.1with the