1、Designation:D5621aStandard Test Method forFlash Point by Tag Closed Cup Tester1This standard is issued under the fixed designation D56;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in parentheses i
2、ndicates the year of last reapproval.Asuperscriptepsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.INTRODUCTIONThis dynamic flash point test method employs a prescribed rate of temperature
3、 rise for the materialunder test.The rate of heating may not in all cases give the precision quoted in the test method becauseof the low thermal conductivity of certain materials.To improve the prediction of flammability,TestMethod D3941,which utilizes a slower heating rate,was developed.Test Method
4、 D3941 providesconditions closer to equilibrium where the vapor above the liquid and the liquid are at about the sametemperature.If a specification requires Test Method D56,do not change to Test Method D3941 orother test method without permission from the specifier.Flash point values are a function
5、of the apparatus design,the condition of the apparatus used,andthe operational procedure carried out.Flash point can therefore only be defined in terms of a standardtest method,and no general valid correlation can be guaranteed between results obtained by differenttest methods,or with test apparatus
6、 different from that specified.1.Scope*1.1 This test method covers the determination of the flashpoint,by Tag manual and automated closed testers,of liquidswith a viscosity below 5.5 mm2/s(cSt)at 40 C(104 F),orbelow 9.5 mm2/s(cSt)at 25 C(77 F),and a flash point below93 C(200 F).1.1.1 Two sets of tes
7、t conditions are used within this testmethod:low temperature(LT)test conditions for expectedflash points 60 C,and high temperature(HT)test conditionsfor expected flash points of 60 C.1.1.2 For the closed-cup flash point of liquids with thefollowing properties:a viscosity of 5.5 mm2/s(cSt)or more at4
8、0 C(104 F);a viscosity of 9.5 mm2/s(cSt)or more at 25 C(77 F);a flash point of 93 C(200 F)or higher;a tendency toform a surface film under test conditions;or containingsuspended solids,Test Method D93 can be used.1.1.3 For cut-back asphalts refer to Test Methods D1310and D3143.NOTE1The U.S.Departmen
9、t of Transportation(RSTA)2and U.S.Department of Labor(OSHA)have established that liquids with a flashpoint under 37.8 C(100 F)are flammable as determined by this testmethod for those liquids that have a viscosity less than 5.5 mm2/s(cSt)at40 C(104 F)or 9.5 mm2/s(cSt)or less at 25 C(77 F),or do notco
10、ntain suspended solids or do not have a tendency to form a surface filmwhile under test.Other flash point classifications have been established bythese departments for liquids using this test method.1.2 This test method can be used to measure and describethe properties of materials,products,or assem
11、blies in responseto heat and flame under controlled laboratory conditions andcannot be used to describe or appraise the fire hazard or firerisk of materials,products,or assemblies under actual fireconditions.However,results of this test method can be used aselements of fire risk assessment that take
12、s into account all ofthe factors that are pertinent to an assessment of the fire hazardof a particular end use.1.3 Related standards are Test Methods D93,D1310,D3828,D3278,and D3941.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and
13、 is the direct responsibility ofSubcommittee D02.08 on Volatility.Current edition approved Dec.1,2021.Published December 2021.Originallyapproved in 1918.Last previous edition approved in 2021 as D56 21.DOI:10.1520/D0056-21A.2For information on United States Department of Transportation regulations,s
14、eeCodes of United States Regulation 49 CFR Chapter 1 and for information on UnitedStates Department of Labor regulations,see Code of United States Regulation 29CFR Chapter XVII.Each of these items are revised annually and may be procuredfrom the Superintendent of Documents,Government Printing Office
15、,Washington,DC 20402.*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 StatesThis international standard was developed in accordance with internationally recognized principles on stan
16、dardization 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.11.4 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.1.5 WARNINGMercury has been designated by manyregulatory agencies as a hazardous substance that can causeserious medical issues.Mercury,or its vapor,has been dem-onstrated