1、Designation: D1929 14Standard Test Method forDetermining Ignition Temperature of Plastics1This standard is issued under the fixed designation D1929; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe
2、r 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 fire test response test method2covers a laboratorydetermination of the flash ignition temperature and spontane-ous ignition temperatur
3、e of plastics using a hot-air furnace.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 CautionDuring the course of combustion, gases orvapors, or both, are evolved that have the potential to behazardous to personnel.1.4 T
4、his standard is used to measure and describe theresponse of materials, products, or assemblies to heat andflame under controlled conditions, but does not by itselfincorporate all factors required for fire-hazard or fire-riskassessment of the materials, products, or assemblies underactual fire condit
5、ions.1.5 Fire testing is inherently hazardous. Adequate safe-guards for personnel and property shall be employed inconducting these tests.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
6、establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statements are given in 1.3 and 1.4.NOTE 1This test method and ISO 871-1996 are identical in alltechnical details.2. Referenced Documents2.1 ASTM Standa
7、rds:3D618 Practice for Conditioning Plastics for TestingE176 Terminology of Fire Standards2.2 International Standards:4ISO 871-1996 PlasticsDetermination of Ignition Tempera-ture Using a Hot-Air FurnaceISO 5725 Precision of Test MethodsDetermination ofRepeatability and Reproducibility for Standard T
8、est Meth-ods by Interlaboratory TestsIEC 584-2 ThermocouplesPart 2: Tolerances3. Terminology3.1 For definitions of terms relating to fire, see TerminologyE176.3.2 Definitions of Terms Specific to This Standard:3.2.1 flash ignition temperature (FIT)the minimum tem-perature at which, under specified t
9、est conditions, sufficientflammable gases are emitted to ignite momentarily uponapplication of a small external pilot flame.3.2.2 glowing combustioncombustion of a material in thesolid phase without flame but with emission of light from thecombustion zone, caused by slow decomposition and carbon-iza
10、tion at various points in the specimen, without generalignition occurring.3.2.3 spontaneous ignition temperature or self-ignition tem-perature (SIT)the minimum temperature at which the self-heating properties of the specimen lead to ignition or ignitionoccurs of itself, under specified test conditio
11、ns, in the absenceof any additional flame ignition source.4. Significance and Use4.1 Tests made under conditions herein prescribed can be ofconsiderable value in comparing the relative ignition charac-teristics of different materials. Values obtained represent thelowest ambient air temperature that
12、will cause ignition of the1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.30 on Thermal Proper-ties.30.03).Current edition approved Dec. 1, 2014. Published December 2014. Originallyapproved in 1962. Last previous editi
13、on approved in 2013 as D1929 13a.DOI:10.1520/D1929-14.In 1996, this test method was totally revised to be technically equal to ISO871-1996, and a specific air velocity is specified, which eliminates the need forapproximations.2The following reference may be of interest in connection with this test m
14、ethod:Stetchkin, N. P., “A Method and Apparatus for Determining the Ignition Charac-teristics of Plastics,” Journal of Research, National Institute of Standards andTechnology, Vol 43, No. 6, December 1949 (RP 2052), p. 591.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orconta
15、ct 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 American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.*A Summary
16、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 States1material under the conditions of this test. Test values areexpected to rank materials according to ignition susceptibilityunder actu
17、al use conditions.4.2 This test is not intended to be the sole criterion for firehazard. In addition to ignition temperatures, fire hazardsinclude other factors such as burning rate or flame spread,intensity of burning, fuel contribution, products of combustion,and others.5. Apparatus5.1 Hot-Air Ign
18、ition FurnaceA furnace similar to thatshown in Fig. 1, consisting primarily of an electrical heatingunit and specimen holder.5.2 Furnace TubeA vertical tube with an inside diameterof 100 6 5 mm and a length of 230 6 20 mm, made of aceramic that will withstand at least 750C. The vertical tubestands o
19、n the furnace floor, fitted with a plug for the removal ofaccumulated residue.5.3 Inner Ceramic TubeAceramic tube that will withstandat least 750C, with an inside diameter of 75 6 5 mm, lengthof 2306 20 mm, and thickness of approximately 3 mm, placedinside the furnace tube and positioned 20 6 2 mm a
20、bove thefurnace floor on three small spacer blocks. The top is coveredFIG. 1 Cross Section of Hot-Air Ignition FurnaceD1929 142by a disk of heat-resistant material with a 25 6 2-mm diameteropening in the center that is used for observation and passageof smoke and gases. The pilot flame is located im
21、mediatelyabove the opening.NOTE 2Fire resistant materials such as silica glass and stainless steelhave also been found suitable for this application.5.4 Air SourceAn outside air source to supply clean airnear the top of the annular space between the ceramic tubes,through a copper tube at a steady an
22、d controllable rate. Airshall be heated and circulated in the space between the twotubes and enter the inner furnace tube at the bottom. Air shallbe metered by a rotameter or other suitable device.5.5 Electrical Heating Unit, contained within the mineralfiber sleeve and constructed of 50 turns of 1.
23、3 6 0.1 mmNichrome V alloy wire, wound around the furnace tube andembedded in heat-resistant cement.NOTE 3Other constructions such as finely coiled wire embedded inmolded ceramic fiber have also been found to be acceptable.5.6 Insulation, consisting of a layer of mineral fiber, ap-proximately 60-mm
24、thick, and covered by a metal jacket.5.7 Pilot Igniter, consisting of a nominal 1.8 6 0.3-mminside diameter (ID) copper tubing attached to a gas supply of94 % minimum purity propane and placed horizontally 5 6 1mm above the top surface of the disk cover. The pilot flameshall be adjusted to 20 6 2 mm
25、 in length and centered abovethe opening in the disk cover.5.8 Specimen Support and HolderThe specimen pan con-sists of a metal container of approximately 0.5-mm thick steelmeasuring 406 2 mm in diameter by 15 6 2 mm in depth. Itis held in a ring of approximately 2.0-mm diameter stainlesssteel weldi
26、ng rod. The ring is welded to a length of the sametype of rod extending through the cover of the furnace, asshown in Fig. 1. The bottom of the specimen pan shall belocated 185 6 5 mm down from the top of the inner furnacetube.5.9 Thermocouples, 0.5-mm diameter, Chromel-Alumel(Type K) or Iron-Constan
27、tan (Type J), for temperature mea-surement connected to a calibrated recording instrument with atolerance not exceeding 62C. The thermocouple toleranceshall be in accordance with IEC 584-2, Table 1, Class 2 orbetter.5.10 Heating ControlAsuitable variable transformer or anautomatic controller connect
28、ed in series with the heating coils.5.11 Timing Device, having an accuracy of at least 1 s.6. Location of Thermocouples6.1 Thermocouple TC1measures the temperature, T1,ofthespecimen. It is located as close as possible to the center of theupper surface of the specimen when the specimen is in placewit
29、hin the furnace. The thermocouple wire is attached to thespecimen support rod.6.2 Thermocouple TC2gives some indication of thetemperature, T2, of the air traveling past the specimen. It islocated 10 6 2 mm below the center of the specimen pan. Thethermocouple wire is attached to the specimen support
30、 rod.NOTE 4Thermocouple TC2may be installed through a hole drilledadjacent to the inspection plug below the specimen pan.6.3 Thermocouple TC3measures the temperature, T3, of theheating coil. It is located adjacent to the furnace heating coiland is used as a reference for temperature adjustment purpo
31、ses.A metallic sheathed thermocouple with a diameter not greaterthan 1.7 mm is permitted to be used for thermocouple TC3. Thelimit on thermocouple thickness in 5.9 does not apply tothermocouple TC3.7. Test Specimens7.1 It is acceptable to use as test specimens materials, orproducts, supplied in any
32、form, with some examples beingpellets, powders and films. It is also acceptable to use com-posites as test specimens. The test report shall include fulldetails of the form in which the test specimens have beentested.NOTE 5Specimens containing high levels of inorganic fillers aredifficult to evaluate
33、.NOTE 6In some cases the same material will give different results iftested in different forms.7.2 A specimen mass of 3.0 6 0.2 g shall be used formaterials having a density greater than 100 kg/m3.7.2.1 Instructions for Specific Types of Test Specimens:7.2.1.1 For sheet materials, cut the sheet into
34、 squares of 206 2by206 2 mm maximum size, and stack these to a heightthat gives the required specimen mass.7.2.1.2 For film materials, roll a strip 20 6 2 mm wide andof length sufficient to give the required specimen mass.7.2.1.3 For cellular materials having a density less than100kg/m3, remove any
35、outer skin and cut the specimens in theform of a block measuring 20 6 2by206 2by506 5 mm.7.3 Sufficient material is required for at least two determi-nations.7.4 The test specimens shall be conditioned at 23 6 2C and50 6 10 % relative humidity for not less than 40 h prior to test,in accordance with
36、Practice D618.8. Procedure8.1 Flash Ignition Temperature (FIT):8.1.1 Set the air velocity to 25 mm/s by adjusting the actualair flow rate through the full section of the inner tube at thefurnace temperature, using the following formula:Qv5 6.62 3293Twhere:Qv= air flow rate, L/min, andT = temperature
37、, K, at T2.Ensure that the air flow rate is maintained at 610 % of thecalculated value.8.1.2 Adjust the electric current supplied to the heating coilby means of the variable transformer or automatic controller,by reference to temperature T3until the air temperature, T2,remains constant at the desire
38、d initial test temperature.8.1.2.1 The default initial test temperature shall be 400Cwhen no prior knowledge of the probable ignition temperatureof the material or product to be tested is available.D1929 1438.1.2.2 If the approximate ignition temperature of the ma-terial or product to be tested is k
39、nown, set the initial testtemperature to 50C below the expected ignition temperature.8.1.3 Proceed as shown in 8.1.3.1 through 8.1.3.4 to assessthe flash ignition temperature. Ignition is likely to be followedby continuous burning of the specimen.8.1.3.1 Raise the specimen pan to the cover opening,
40、andplace the specimen on the pan.8.1.3.2 Lower the pan into the furnace, while ensuring thatthermocouples TC1and TC2are in their correct position, as per6.1 and 6.2.8.1.3.3 Start the timer and ignite the pilot flame.8.1.3.4 Watch for the occurrence of the following events,any one of which represents
41、 evidence of ignition:(1) flaming combustion of the specimen,(2) glowing combustion of the specimen,(3) flash,(4) explosion,(5) rapid rise in temperature T1above that of T2.8.1.4 At the end of 10 min, depending on whether ignitionhas or has not occurred, lower or raise the temperature T2by50C accord
42、ingly, and repeat the test with a fresh specimen.8.1.5 When the range within which the flash ignition tem-perature lies has been determined, begin the test 10C belowthe highest temperature within this range, and continue bydropping the temperature in 10C steps until the temperature isreached at whic
43、h there is no ignition during a 10 min period.8.1.6 Record the lowest air temperature, T2, at which a flashis observed, during the 10 min period, as the flash ignitiontemperature.8.2 Spontaneous Ignition Temperature (SIT):8.2.1 Follow the same procedure as described in 8.1 withtwo exceptions:(1) do
44、not use pilot flame;(2) use the evidences of ignition listed in 8.2.2 instead ofthose listed in 8.1.3.4.8.2.2 The occurrence of any one of the following events isconsidered evidence of spontaneous ignition:(1) flaming combustion of the specimen;(2) glowing combustion of the specimen;(3) rapid rise i
45、n temperature of T1above that of T2.NOTE 7With some materials, it is difficult to detect spontaneousignition visually when burning is by glowing combustion rather thanflaming combustion. In such cases, a rapid rise in termperature, T1aboveT2, is a more reliable reference.8.2.3 Record the lowest air
46、temperature, T2, at which thespecimen burns, during the 10 min period, as the spontaneousignition temperature.9. Test Report9.1 Report the following information:9.1.1 Reference to this test method;9.1.2 Designation of the material, including the name of themanufacturer and composition;9.1.3 Form of
47、the material (granules, sheet, etc.);9.1.4 Mass of the test specimen, g;9.1.5 Density of the cellular test specimens, kg/m3;9.1.6 Flash ignition temperature (FIT), C;9.1.7 Spontaneous ignition temperature (SIT), C;9.1.8 Whether the combustion observed was flaming orglowing;9.1.9 Observations regardi
48、ng the behavior of the specimenduring the test (how ignition occurred, the formation of soot orsmoke, excessive foaming, melting, bubbling, smoking, etc.);and9.1.10 The following statement:“These test results relate only to the behavior of testspecimens under the particular conditions of the test. T
49、hey arenot intended to be used, and shall not be used, to assess thepotential fire hazards of a material in use.”10. Precision and Bias10.1 Relative precision data based on a preliminary inter-laboratory study conducted in 1994, using ISO/DIS 871 asprotocol, is indicated in Appendix X1. Findings from thisinterlaboratory study resulted in changes to the procedure;therefore, another interlaboratory study was initiated in 2012.10.2 Precision5The repeatability standard deviation froma single operator is shown in Table 1 and Table 2.TABLE 1 FIT (C)Mate
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