1、Designation: E502 07 (Reapproved 2013)Standard Test Method forSelection and Use of ASTM Standards for the Determinationof Flash Point of Chemicals by Closed Cup Methods1This standard is issued under the fixed designation E502; the number immediately following the designation indicates the year ofori
2、ginal 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 covers the determination of the flashpoint of
3、 liquid and solid chemical compounds flashing frombelow 10 to 370C (16 to 700F). The procedures andapparatus in Test Methods D56, D93, D3278, D3828, andD3941 are to be used. Modification to these procedures arespecified for tests on solids and viscous liquids. The signifi-cance of the results obtain
4、ed is discussed along with possiblesources of error and factors that might cause interference.1.2 Suggestions for adapting this procedure to mixtures ofchemicals are included (see Appendix X2).1.3 This test method should be used to measure and describethe properties of materials, products, or assemb
5、lies in responseto heat and flame under controlled laboratory conditions andshould not be used to describe or appraise the fire hazard or firerisk of materials or assemblies under actual fire conditions.However, results of this test method may be used as elementsof a fire risk assessment that take i
6、nto account all of the factorsthat are pertinent to an assessment of the fire hazard of aparticular end use.1.4 WarningMercury has been designated by EPA andmany state agencies as a hazardous material that can causecentral nervous system, kidney and liver damage. Mercury, orits vapor, may be hazardo
7、us to health and corrosive tomaterials. Caution should be taken when handling mercury andmercury containing products. See the applicable product Ma-terial Safety Data Sheet (MSDS) for details and EPAs website http:/www.epa.gov/mercury/faq.htm - for additional infor-mation. Users should be aware that
8、 selling mercury and/ormercury containing products into your state may be prohibitedby state law.1.5 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
9、practices and determine the applica-bility of regulatory limitations prior to use. See also Section 8.2. Referenced Documents2.1 ASTM Standards:2D56 Test Method for Flash Point by Tag Closed Cup TesterD92 Test Method for Flash and Fire Points by ClevelandOpen Cup TesterD93 Test Methods for Flash Poi
10、nt by Pensky-MartensClosed Cup TesterD270 Methods of Sampling Petroleum and Petroleum Prod-ucts (Withdrawn 1984)3D1310 Test Method for Flash Point and Fire Point of Liquidsby Tag Open-Cup ApparatusD3278 Test Methods for Flash Point of Liquids by SmallScale Closed-Cup ApparatusD3827 Test Method for E
11、stimation of Solubility of Gases inPetroleum and Other Organic LiquidsD3828 Test Methods for Flash Point by Small Scale ClosedCup TesterD3934 Test Method for Flash/No Flash TestEquilibriumMethod by a Closed-Cup ApparatusD3941 Test Method for Flash Point by the EquilibriumMethod With a Closed-Cup App
12、aratusE681 Test Method for Concentration Limits of Flammabilityof Chemicals (Vapors and Gases)E1232 Test Method for Temperature Limit of Flammabilityof Chemicals3. Terminology3.1 Definitions:3.1.1 flash pointthe lowest temperature, corrected to apressure of 760 mm Hg (101.3 kPa) (1013 mbar) at which
13、application of an ignition source causes the vapors of aspecimen to ignite under specified conditions of test.1This test method is under jurisdiction of ASTM Committee E27 on HazardPotential of Chemicals and is the direct responsibility of Subcommittee E27.04 onFlammability and Ignitability of Chemi
14、cals.Current edition approved Oct. 1, 2013. Published October 2013. Originallyapproved in 1984. Last previous edition approved in 2007 as E502 071. DOI:10.1520/E0502-07R13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For An
15、nual 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. Unite
16、d States14. Summary of Test Method4.1 The specimen is placed in a closed cup and in the smallscale method equilibrated at a test temperature, in the Pensky-Martens Method heated at a controlled rate with stirring, and inthe Tag Method also heated at a controlled rate but withoutstirring. A small fla
17、me is directed into the vapor space of eachcup at specified intervals, with simultaneous interruption ofstirring in the Pensky-Martens Method, to determine whether aflash occurs or not. In Test Method D3941, the specimen isheated at a slower rate than in the other controlled heatingmethods, maintain
18、ing a small temperature differential betweenbath and specimen.5. Significance and Use5.1 The flash point measures the response of the sample toheat and flame under controlled laboratory conditions. It isonly one of a number of properties that must be considered inassessing the overall flammability h
19、azard of a material.5.2 As a result of physical factors inherent in the apparatusand procedure, the closed cup flash point does not necessarilyrepresent the minimum temperature at which a material canevolve flammable vapors, and the absence of a flash point doesnot guarantee nonflammability (see App
20、endix X1 and Appen-dix X2).5.3 Flash point is used in shipping and safety regulations todefine flammable and combustible materials. Test MethodsD56, D93, and D3278 are specified as test methods fordetermining the flash point of these materials.5.4 If the process or handling conditions dictate the us
21、age ofa flammable material at temperatures ranging upward from 5 to10C below the closed-cup flash point, then a flammable vapormight be present above the liquid. In such cases, it may bemore appropriate to use the temperature limit of flammability(as determined by Test Method E1232) instead of flash
22、 point.5.5 Small scale methods involving equilibrium proceduresand only one flame pass per specimen are preferred.6. Interferences6.1 Incorrect flash points can be obtained when testingchemicals corrosive to the materials of construction of the cup.(For example, certain amines and acid chlorides rea
23、ct with thestandard aluminum small scale cup causing erroneously lowflash points, perhaps due to hydrogen formation.) Cups em-ploying alternative materials of construction, electroplating orplastic coating can provide corrosion resistance. Results innon-standard cups, particularly in non-equilibrium
24、 tests, maydiffer slightly from those obtained in this test method.7. Apparatus7.1 Tag Closed-Cup Tester, including thermometers, shall beas shown in Test Methods D56 and D3941.7.2 Penksy-Martens Closed-Cup Tester, includingthermometers, shall be as shown in Test Methods D93.7.3 Small scale Closed T
25、ester, including thermometers, shallbe as shown in Test Methods D3278 or D3828.NOTE 1Some automatic flash point testers may save testing time andpermit the use of small samples. If automatic testers are used, the usermust be certain that all instructions for calibration and operation arefollowed to
26、ensure that the results are equivalent to those obtained on theASTM standard equipment. For regulation purposes or in cases of dispute,the flash point as determined on the manual tester shall be the acceptedvalue.NOTE 2ASTM thermometers 33C or 33F may be used in the TagTester instead of those specif
27、ied in Test Method D56 when conductingtests at temperatures below 10C (14F). Slight stem corrections may benecessary and care should be taken to avoid freezing the mercury in thethermometer by cooling below 40C (40F).7.4 Shield, as described in Test Method D3941 or Test Method D1310.8. Hazards8.1 To
28、xicity of Chemical and Combustion Products:8.1.1 Isolate or control operations on toxic or corrosivematerials to prevent exposure to any personnel.8.1.2 Since flash point tests are conducted in still air, the useof forced circulation for removal of toxic or nuisance fumes orcombustion products is re
29、stricted. However, a laboratory fumehood equipped with an exhaust damper that can be completelyclosed provides an ideal location for maintaining draft-freeconditions and provides the ability to readily exhaust danger-ous vapors and combustion products when necessary.8.1.3 Use respiratory and splash
30、protective devices as ap-propriate with toxic or corrosive materials. In most cases,approved cartridge respirators are adequate respiratory protec-tion for the concentrations normally encountered in flash-pointtesting. Certain toxic or unusual materials, however, mayrequire an air-supplied respirato
31、r and extreme cases mayrequire complete protective coverage such as an air-suppliedplastic suit. (Two examples of the latter type of material aredimethyl sulfate and pure mercaptans.) Tests on these highlytoxic or obnoxious materials may also be conducted in com-pletely isolated, closed systems, suc
32、h as glove boxes. In thiscase, procedures should ensure an uncontaminated air systemin the box, and should prevent a buildup of vapors from thematerial under test.8.2 Dry Ice Use:8.2.1 Exercise care in the use of dry ice for sample andapparatus cooling. Avoid contact with dry ice to preventfrostbite
33、. Glass bottles or vials of chemicals should not beplaced directly in dry ice or dry ice baths because of thepossibility of breakage due to thermal shock.8.3 Tests of Explosives and Propellants:8.3.1 Flash tests should not be conducted on potential orknown explosive or propellant materials without c
34、ompleteprior knowledge that burning will not result in propagation toan explosive decomposition. Properly barricaded or remotelyoperated automatic testers should be used if precise flash pointsare needed.8.4 Pyrophoric Materials:8.4.1 Flash point apparatus is not applicable for the evalu-ation of py
35、rophoric materials and should not be used for thispurpose.9. Preparation of Sample9.1 Obtain samples representative of the batch under test.Methods D270 can be used as a reference on samplingtechniques. With mixtures and with samples containingE502 07 (2013)2impurities, take care to avoid the loss o
36、f volatile componentsduring sampling and handling for testing. When heatingviscous or solid materials for ease of pouring, samples must beheld at temperatures below, or as close as possible to, thosespecified in the various test methods. Discard samples fromleaking or contaminated containers. Sample
37、s that are hygro-scopic should not be exposed to moisture or moist air.9.2 Samples should not be stored in plastic (polyethylene,polypropylene, etc.) bottles, since volatile materials may dif-fuse through the walls of the bottle.10. Preparation of Apparatus10.1 Support the appropriate flash-point te
38、ster on a level,steady work surface in a draft-free location. If a draft-freelocation is not available, use a shield surrounding the tester onthree sides. The shield should be approximately 460 mm (18in.) wide and 610 mm (24 in.) high.NOTE 3An area capable of being partially darkened is advantageous
39、since it aids in the detection of the relatively nonluminous flamessometimes encountered in flash-point testing.NOTE 4Test Method D1310 gives a design for a draft shield suitablefor standard flash-point testers.11. Calibration11.1 Check the condition and operation of the Tag, Pensky-Martens and smal
40、l scale testers as specified in Test MethodsD56, D93, D3278,orD3828, respectively.12. Procedure12.1 Follow the procedures outlined in Test Methods D56 orD3941 (Tag Closed Cup), D3278 or D3827 (Small scaleClosed Cup), and D93 (Pensky Martens Closed Cup), as isnecessary. Certain explanatory notes and
41、procedure modifica-tions not contained in the individual methods are given below.Occasionally, particularly near the temperature of the actualflash point, the application of the test flame will cause a halo ortest flame enlargement that should be ignored. In some casesthis test flame enlargement wil
42、l not lead to a flash point on anincrease in temperature.12.2 For liquids with a viscosity less than 5.8 106m2/s(5.8 cSt) at 38C (100F), or 9.5 106m2/s (9.5 cSt) at 25C(77F), observe the following:NOTE 5The first viscosity threshold point is stated either as“5.8 106m2/s (5.8 cSt) at 100F (38C)”, or
43、as “5.5 106m2/s (5.5cSt) at 40C (104F), in different flash point test standards. The choice isindicative of only the unit system preferred by individual test standards. Inpractice the two forms are considered equivalent.12.2.1 If the flash point is below 93C (200F), use thesmall scale (Test Method D
44、3278 or D3828) or Tag (TestMethod D56) apparatus and procedures.12.2.2 If the flash point is 93C (200F) or above, use thesmall scale (Test Method D3828) or Pensky-Martens (TestMethods D93) apparatus and procedures.NOTE 6The electric heaters on some Tag Testers may be of insuffi-cient capacity to mai
45、ntain the specified heating rates when operating in theupper ranges of this practice. Heat input can be increased slightly by usinga variable transformer to increase the voltage slightly on the heaters.Insulation can be applied to the exterior of the bath to reduce heat losses.NOTE 7With low tempera
46、ture operation in the small scale methods,equilibrium may be difficult to maintain due to heating by naturalconvection. It, therefore, will be necessary to cool the cup and samplebelow the anticipated flash point before specimen introduction (see TestMethods D3278).NOTE 8In the Tag Method (Test Meth
47、od D56), natural warming ratessometimes exceed 1C (2F)/min. These rates can be reduced by insulat-ing the outside of the bath container. A laboratory refrigerated circulatormay be used. One advantage of this system is that circulation of therefrigerant bath with the system gradually warming up can s
48、erve as acontrol on heating rate.NOTE 9With low-temperature operation in the Tag and Small scaleMethods, difficulties can be created by the formation of frost on thesurface of the tester. If precise flash points are needed in the temperaturerange where frost conditions are encountered, tests can be
49、conducted in adry box or a room of very low humidity.When ice formation on the lid andcover parts cannot be avoided, the results will be unreliable. Sticking ofthe slide due to ice formation can be minimized by carefully lubricatingthe slide with a high vacuum silicone lubricant. Portions of the cover andslide in the vicinity of the pilot flame and openings should be wiped freeof frost just prior to the initial flame insertion at 5C (10F) below theflash point.12.3 For liquids with a viscosity equal to or greater than5.8106m
