ASTM_D_4391_-_18a.pdf

Designation:D439118aStandard Terminology Relating toThe Burning Behavior of Textiles1This standard is issued under the fixed designation D4391;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.The definitions in this standard have been approved by the Society and are included in D123“Terminology Relating to Textiles”.Theyare published as a separate collection for the convenience of persons interested in the burning behavior of textiles.A bibliography ofrelated literature is given in Appendix X1.afterflame,npersistent flaming of a material after the igni-tion source has been removed.D13.92 D4391after-flame time,nthe length of time for which a materialcontinues to flame after the ignition source has beenremoved.D13.92 D4391afterglow,nglow in material after the removal of an externalignition source or after the cessation(natural or induced)offlaming of the material.(See also flame,glow,and smol-dering.)afterglow time,nthe time afterglow continues after thecessation of flaming or after removal of the ignition source.D13.92 D4391base burn,nthe point at which the flame burns the ground(base)fabric of a raised surface textile fabric and provides aself-sustaining flame.DISCUSSIONBase burn is also known as base fabric ignition orfusing.The base burns used to establish a Class 3 fabric are those burnsresulting from surface flash that occur on specimens in places otherthan the point of impingement when the warp and fill yarns of a raisedsurface textile fabric undergo combustion.Base burns can be identifiedby an opacity change,scorching on the reverse side of the fabric,orwhen a physical hole is evident.burn time,nthe time elapsed from ignition until the stopthread is severed as measured by the timing mechnsim of thetest apparatus.burning behavior,nall the changes that take place whenmaterials or products are exposed to a specified ignitionsource.charring,nthe formation of carbonaceous residue as theresult of pyrolysis or incomplete bustible textile,na textile that will ignite and burn orthat will give off vapors that will ignite and burn whensubjected to external sources of ignition.(Compare flam-mable textile,noncombustible textile.)combustion,na chemical process of oxidation that occurs ata rate fast enough to produce heat and usually light either asglow or flames.DISCUSSIONSome oxidation such as that of hydrogen emits radia-tion outside the visible spectrum.critical sewn seams,nin assembly of flame resistant textiles,those sewn junctions where failure would result in immedi-ate danger or injury.dangerously flammable textile,n not defined.This term isimplied in the Standard for the Flammability of ClothingTextiles(16 CFR Part 1610)under the Flammable FabricsAct(15 USC 1191,et seq.)from which a meaning can beinferred.(See also flammable textile.)dripping,nas related to the burning of a textile,liquefiedmaterial that separates and falls from a textile.DISCUSSIONThe liquefied material can demonstrate continuedmelting,burning,flaming,or smoldering as it separates and falls fromthe textile.This can be significant relative to the performance charac-teristics of the textile.embrittlement,nthe formation of a brittle residue as theresult of pyrolysis or incomplete combustion.exposure energy to thermal end point,nthe thermal energytransferred through a specimen that is sufficient to causeignition of contiguous materials.D13.92 D7140fire,nas related to textile flammability,an uncontrolledconflagration in which materials are destroyed by burning asevidenced by flames of varying size and shape,and a highintensity heat source of 5 kw or greater,such as a burningwaste basket,grease-fire on a stove,burning building orforest fire.flame,nas related to textile flammability,a hot luminouszone of gas or matter in gaseous suspension,or both,that isundergoing combustion,that is relatively constant in sizeand shape,and that produces a relatively low heat flux.(Compare fire.)1This terminology is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.92 on Terminology.Current edition approved July 1,2018.Published August 2018.Originallyapproved in 1984.Last previous edition approved in 2018 as D4391 18.DOI:10.1520/D4391-18A.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 DISCUSSIONExamples are a match flame,candle flame,or a Bunsenburner gas flame.flame application time,nthe time fo