ASTM_D_3874_-_13.pdf

Designation:D387413Standard Test Method forIgnition of Materials by Hot Wire Sources1This standard is issued under the fixed designation D3874;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.Scope*1.1 This test method is intended to differentiate,in apreliminary fashion,among materials with respect to theirresistance to ignition because of their proximity to electrically-heated wires and other heat sources.21.2 This test method applies to molded or sheet materialsavailable in thicknesses ranging from 0.25 to 6.4 mm(0.010 to0.25 in.).1.3 This test method applies to materials that are rigid atnormal room temperatures.That is,it applies to materials forwhich the specimen does not deform during preparation,especially during the wire-wrapping step described in 10.1.Examples of deformation that render this test method inappli-cable include:1.3.1 Bowing,in either a transverse or a longitudinaldirection,or twisting of the specimen,during the wire-wrapping step,to a degree visible to the eye.1.3.2 Visible indentation of the wrapped wire into thespecimen.1.4 The values stated in SI units are to be regarded as thestandard.The inch-pound units given in parentheses are forinformation only.(See SI10 for further details.)1.5 This test method measures and describes the response ormaterials,products,or assemblies to heat and flame undercontrolled conditions,but does not by itself incorporate allfactors required for fire hazard or fire risk assessment of thematerials,products,or assemblies under actual fire conditions.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.1.7 Fire testing is inherently hazardous.Adequate safe-guards for personnel and property shall be employed inconducting these tests.NOTE1Although this test method and IEC 60695-2-20,differ inapproach and in detail,data obtained using either are technically equiva-lent.2.Referenced Documents2.1 ASTM Standards:3D1711 Terminology Relating to Electrical InsulationE176 Terminology of Fire StandardsIEEE/ASTM SI-10 American National Standard for MetricPractice2.2 IEC Standards:IEC 60695-2-20 Fire Hazard TestingSection 20:Glowing/Hot-wire Based Test Methods,Hot-wire Coil IgnitabilityTest on Materials4IEC 60695-4 Fire Hazard TestingPart 4:TerminologyConcerning Fire Tests42.3 ISO StandardsISO 13943 Fire SafetyVocabulary53.Terminology3.1 Definitions:3.1.1 Use Terminology E176 and ISO 13943 and IEC60695-4 for definitions of terms used in this test method andassociated with fire issues.Where differences exist indefinitions,those contained in Terminology E176 shall be used.Use Terminology D1711 for definitions of terms used in thistest method and associated with electrical insulation materials.3.2 Definitions of Terms Specific to This Standard:3.2.1 ignition,ninitiation of flaming produced by combus-tion in the gaseous phase that is accompanied by the emissionof light.1This test method is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.21 on Fire Performance Standards.Current edition approved Nov.1,2013.Published December 2013.Originallyapproved in 1988.Last previous edition approved in 2012 as D3874120.DOI:10.1520/D3874-13.2K.N.Mathes,Chapter 4,“Surface Failure Measurements”,EngineeringDielectrics,Vol.IIB,Electrical Properties of Solid Insulating Materials,Measure-ment Techniques,R.Bartnikas,Editor,ASTM STP 926,ASTM,Philadelphia,1987.3For 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.4Available from International Electrotechnical Commission(IEC),3 rue deVaremb,Case postale 131,CH-1211,Geneva 20,Switzerland,http:/www.iec.ch.5Available from International Organization for Standardization(ISO),1,ch.dela Voie-Creuse,Case postale 56,CH-1211,Geneva 20,Switzerland,http:/www.iso.ch.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.Summary of Test Method4.1 In this test method,a rectangular bar-shaped testspecimen,with the center portion wrapped with a coil of heaterwire,is supported horizontally at both ends.The circuit is thenenergized by applying a fixed power density to the heater wire,which rapidly heats up.The behavior of the test specimen isobserved.until one of the following happens:(a)the materialunder tes