1、Designation: E 502 07e1Standard 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 E 502; the number immediately following the designation indicates the year oforiginal adoption
2、 or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.e1NOTEMercury warning editorially added in March 2008.1. Scope1.1 This test method cove
3、rs the determination of the flashpoint of liquid and solid chemical compounds flashing frombelow 10 to 370C (16 to 700F). The procedures andapparatus in Test Methods D 56, D 93, D 3278, D 3828, andD 3941 are to be used. Modification to these procedures arespecified for tests on solids and viscous li
4、quids. The signifi-cance of the results obtained 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 describeth
5、e properties of materials, products, or assemblies 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
6、 elementsof a fire risk assessment that take into account all of the factorsthat are pertinent to an assessment of the fire hazard of aparticular end use.1.4 WARNING Mercury has been designated by EPAandmany state agencies as a hazardous material that can causecentral nervous system, kidney and live
7、r damage. Mercury, orits vapor, may be hazardous 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 addit
8、ional infor-mation. Users should be aware that 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 standar
9、d to establish appro-priate safety and health 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 Clevelan
10、dOpen Cup TesterD93 Test Methods for Flash Point by Pensky-MartensClosed Cup TesterD 270 Method of Sampling Petroleum and Petroleum Prod-ucts3D 1310 Test Method for Flash Point and Fire Point ofLiquids by Tag Open-Cup ApparatusD 3278 Test Methods for Flash Point of Liquids by SmallScale Closed-Cup A
11、pparatusD 3827 Test Method for Estimation of Solubility of Gasesin Petroleum and Other Organic LiquidsD 3828 Test Methods for Flash Point by Small Scale ClosedCup TesterD 3934 Test Method for Flash/No Flash TestEquilibriumMethod by a Closed-Cup ApparatusD 3941 Test Method for Flash Point by the Equi
12、libriumMethod With a Closed-Cup ApparatusE 681 Test Method for Concentration Limits of Flammabil-ity of Chemicals (Vapors and Gases)E 1232 Test Method for Temperature Limit of Flammabilityof Chemicals3. Terminology3.1 Definition:3.1.1 flash pointthe lowest temperature, corrected to apressure of 760
13、mm Hg (101.3 kPa) (1013 mbar) at which1This 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 Chemicals.Current edition approved Jan. 15, 2007. Published March 2007. Origi
14、nallyapproved in 1984. Last previous edition approved in 2006 as E 50206a.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
15、ASTM website.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.application of an ignition source causes the vapors of aspecimen to ignite under specified conditions of test.4. Summary of Test Method4.1 The specimen is placed
16、 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 flame is directed into the vapor space of eachcup at specified
17、intervals, with simultaneous interruption ofstirring in the Pensky-Martens Method, to determine whether aflash occurs or not. In Test Method D 3941, the specimen isheated at a slower rate than in the other controlled heatingmethods, maintaining a small temperature differential betweenbath and specim
18、en.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 hazard of a material.5.2 As a result of physical factors inh
19、erent 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 Appendix X1 and Appen-dix X2).5.3 Flash point is used in shipp
20、ing and safety regulations todefine flammable and combustible materials. Test MethodsD 56, D 93, and D 3278 are specified as test methods fordetermining the flash point of these materials.5.4 If the process or handling conditions dictate the usage ofa flammable material at temperatures ranging upwar
21、d 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 E 1232) instead of flash point.5.5 Small scale methods involving equilibrium pr
22、oceduresand 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 react with thestandard aluminum small scale cup causing er
23、roneously 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 tests, maydiffer slightly from those obtained in this
24、test method.7. Apparatus7.1 Tag Closed-Cup Tester, including thermometers, shallbe as shown in Test Methods D 56 and D 3941.7.2 Penksy-Martens Closed-Cup Tester, including ther-mometers, shall be as shown in Test Methods D93.7.3 Small scale Closed Tester, including thermometers, shallbe as shown in
25、Test Methods D 3278 or D 3828.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 ensure that the results are equivalent to those o
26、btained 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 specified in Test Method D56when conductingtests at tem
27、peratures 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 D 3941 or Test Method D 1310.8. Hazards8.1 Toxicity of Chemical and Combustion Products:8.1.1
28、 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 restricted. However, a laboratory fumehood equippe
29、d 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 protective devices as ap-propriate with toxic or
30、 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 respirator and extreme cases mayrequire complete protecti
31、ve 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, such as glove boxes. In thiscase, procedures should
32、 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. Glass bottles or vials of chemicals should not
33、 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 completeprior knowledge that burning will not res
34、ult 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 pyrophoric materials and should not be used for th
35、ispurpose.9. Preparation of Sample9.1 Obtain samples representative of the batch under test.Test Method D 270 can be used as a reference on samplingE50207e12techniques. With mixtures and with samples containing impu-rities, take care to avoid the loss of volatile components duringsampling and handli
36、ng for testing. When heating viscous orsolid materials for ease of pouring, samples must be held attemperatures below, or as close as possible to, those specifiedin the various test methods. Discard samples from leaking orcontaminated containers. Samples that are hygroscopic shouldnot be exposed to
37、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 tester on a level,steady work surface in a draft-fr
38、ee 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 advantageoussince it aids in the detection of the relatively
39、nonluminous flamessometimes encountered in flash-point testing.NOTE 4Test Method D 1310 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 small scale testers as specified in Test MethodsD 56
40、, D 93, D 3278, or D 3828, respectively.12. Procedure12.1 Follow the procedures outlined in Test Methods D56or D 3941 (Tag Closed Cup), D 3278 or D 3827 (Small scaleClosed Cup), and D93(Pensky Martens Closed Cup), as isnecessary. Certain explanatory notes and procedure modifica-tions not contained i
41、n 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 will not lead to a flash point on anincreas
42、e in temperature.12.2 For liquids with a viscosity less than 5.8 3 106m2/s(5.8 cSt) at 38C (100F), or 9.5 3 106m2/s (9.5 cSt) at 25C(77F), observe the following:NOTE 5The first viscosity threshold point is stated either as“5.8 3 106m2/s (5.8 cSt) at 100F (38C)”, or as “5.5 3 106m2/s (5.5cSt) at 40C
43、(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 3278 or D 3828) or Tag (TestMet
44、hod D56) apparatus and procedures.12.2.2 If the flash point is 93C (200F) or above, use thesmall scale (Test Method D 3828) or Pensky-Martens (TestMethods D93) apparatus and procedures.NOTE 6The electric heaters on some Tag Testers may be of insuffi-cient capacity to maintain the specified heating r
45、ates 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 temperature operation in the small s
46、cale 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 D 3278).NOTE 8In the Tag Method (Test Method D56), natural warming rat
47、essometimes 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 serve as acontrol on heating
48、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 conducted in adry box or a r
49、oom 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 than5.8 3 106m2/s (5.8 cSt) at 38C (100F), or 9.
