1、Designation: F2702 08F2702 15Standard Test Method forRadiant Heat Performance of Flame Resistant ClothingMaterials with Burn Injury Prediction1This standard is issued under the fixed designation F2702; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、 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 measures thermal protective characteristics of flame resistant textile
3、 materials subjected to a standardizedradiant heat exposure relative to a predicted second-degree skin burn injury.1.1.1 This test method is not applicable to textile materials that are not flame resistant.NOTE 1The determination of a textile materials flame resistance shall be made prior to testing
4、 and done according to the applicable performanceand/or specification standard or specification standard, or both, for the textile materials end-use.1.1.2 This test method accounts for the thermal energy contained in an exposed test specimen after the standardized radiant heatexposure has ceased.1.2
5、 This test method is used to measure and describe the response of materials, products, or assemblies to heat under controlledconditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products,or assemblies under actual fire conditio
6、ns.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversionsto inch-pound or other units that are commonly used for thermal testing.1.4 This standard does not purport to address the safety concerns, if any, associated with its use.
7、 It is the responsibility of theuser of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitationsprior to use.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing
8、 TextilesD1777 Test Method for Thickness of Textile MaterialsD3776 Test Methods for Mass Per Unit Area (Weight) of FabricD4157 Test Method for Abrasion Resistance of Textile Fabrics (Oscillatory Cylinder Method)E457 Test Method for Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) Calo
9、rimeterF1494 Terminology Relating to Protective Clothing2.2 Other Standards:CCC-C-419 Federal Specification for Cloth, Duck, Unbleached, Plied-Yarns, Army and Numbered3. Terminology3.1 Definitions:3.1.1 break-open, nin testing thermal protective materials, a material response evidenced by the format
10、ion of a hole in thetest specimen during the thermal exposure that may result in the exposure energy in direct contact with the heat sensor.3.1.1.1 Discussion1 This test method is under the jurisdiction of ASTM Committee F23 on Personal Protective Clothing and Equipment and is the direct responsibil
11、ity of SubcommitteeF23.80 on Flame and Thermal.Current edition approved July 1, 2008Feb. 1, 2015. Published August 2008February 2015. Originally approved in 2008. Last previous edition approved in 2008 asF2702 08. DOI: 10.1520/F2702-08.10.1520/F2702-15.2 For referencedASTM standards, visit theASTM w
12、ebsite, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indica
13、tion of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be con
14、sidered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1The specimen is considered to exhibit breakopen when a hole is produced as a result of the thermal exposure that is at least 3.2cm2 (0.5 in.2) in area or at
15、 least 2.5 cm (1.0 in.) in any dimension. Single threads across the opening or hole do not reduce thesize of the hole for the purposes of this test method.3.1.2 charring, nthe formation of a carbonaceous residue as the result of pyrolysis or incomplete combustion.3.1.3 dripping, na material response
16、 evidenced by flowing of the polymer.3.1.4 embrittlement, nthe formation of a brittle residue as a result of pyrolysis or incomplete combustion.3.1.5 heat flux, nthe thermal intensity indicated by the amount of energy transmitted divided by area and time; kW/m2(cal/cm2s).3.1.6 ignition, nthe initiat
17、ion of combustion.3.1.7 melting, na material response evidenced by softening of the polymer.3.1.8 radiant heat performance (RHP), nin testing of thermal protective materials, the cumulative amount of transferredenergy identified by the intersection of a measured time-dependent heat transfer response
18、 through a subject material to atime-dependent, empirical predicted second-degree skin burn injury performance curve3, expressed as a rating or value; J/cm2(cal/cm2).3.1.9 response to heat exposure, nin testing of thermal protective materials, the observable response of the textile to theenergy expo
19、sure as indicated by break-open, melting, dripping, charring, embrittlement, shrinkage, sticking, and ignition.3.1.10 second-degree burn injury, nin testing of thermal protective materials, reversible burn damage at the epidermis/dermisinterface in human tissue.3.1.11 shrinkage, na decrease in one o
20、r more dimensions of an object or material.3.1.12 sticking, na material response evidenced by softening and adherence of the material to the surface of itself or anothermaterial.3.1.13 sample test suite, nany number of test specimens used to derive a single thermal performance estimate value.3.1.13.
21、1 Discussionthe determination of a single radiant heat performance estimate value requires exposing a number of specimens under varyingexposure conditions so that the thermal energy left in the sample after the radiant source is removed is considered and accountedfor when determining performance aga
22、inst a burn injury prediction.3.1.14 For the definitions of protective clothing terms used in this method, refer to Terminology F1494, and for other textileterms used in this method, refer to Terminology D123.4. Summary of Test Method4.1 A vertically positioned test specimen is exposed to a radiant
23、heat source with an exposure heat flux of either (a) 21 kW/m2(0.5 cal/cm2s) or (b) 84 kW/m2 (2 cal/cm2s).NOTE 2Other exposure heat flux values are allowed. The test facility shall verify the stability of the exposure level over the material exposure timeinterval (used to determine the radiant heat p
24、erformance value) and include this in the test results report.4.2 The transfer of heat through the test specimen is measured using a copper slug calorimeter.The change in temperature versustime is used, along with the known thermo-physical properties of copper to determine the respective thermal ene
25、rgy delivered.4.3 A Radiant Heat Performance value of the test specimen is determined iteratively as the intersection of the time-dependentcumulative radiant heat response as measured by the calorimeter to a time-dependent, empirical predicted second-degree skin burninjury performance curve identifi
26、ed in 10.2.1.4.4.4 Subjective observations of the thermal response of tested specimens are optionally noted.5. Significance and Use5.1 This test method is intended for the determination of the radiant heat performance value of a material, a combination ofmaterials, or a comparison of different mater
27、ials used in flame resistant clothing for workers exposed to radiant thermal hazards.5.2 This test method evaluates a materials heat transfer properties when exposed to a heat exposure at a constant value andsystematically varied durations.Air movement at the face of the specimen and around the calo
28、rimeter can affect the measured heattransferred due to forced convective heat losses. Minimizing air movement around the specimen and test apparatus will aid in therepeatability of the results.3 Derived from: Stoll, A.M. and Chianta, M.A., “Method and Rating System for Evaluations of Thermal Protect
29、ion”, Aerospace Medicine, Vol 40, 1969, pp. 1232-1238and Stoll, A.M. and Chianta, M.A., “Heat Transfer through Fabrics as Related to Thermal Injury”,Injury,” Transactions New York Academy of Sciences, Vol 33 (7), Nov.1971, pp. 649-670.F2702 1525.3 This test method accounts for the thermal energy con
30、tained in the exposed test specimen after the radiant heat exposure hasceased. Higher values of Radiant Heat Performance rating determined in this test associate to higher values of radiant energyprotection against a predicted skin burn injury.5.4 This test method maintains the specimen in a static,
31、 vertical position and does not involve movement except that resultingfrom the exposure procedure.5.5 This test method specifies two standard sets of exposure conditions, 21 kW/m2 (0.5 cal/cm2s) and 84 kW/m2 (2.0 cal/cm2s).Either can be used.5.5.1 If a different set of exposure conditions is used, i
32、t is likely that different results will be obtained.5.5.2 The optional use of other conditions representative of the expected hazard, in addition to the standard set of exposureconditions, is permitted. However, the exposure conditions used must be reported with the results along with a determinatio
33、n ofthe exposure energy level stability.6. Apparatus and Materials6.1 General ArrangementThe apparatus consists of a vertically oriented radiant heat source, specimen holder assembly,protective shutter, sensor assembly, and data acquisition/analysis system. The general arrangement of the radiant hea
34、t source,specimen holder, and protective shutter of a suitable apparatus is shown in Fig. 1.6.1.1 Radiant Heat SourceA suitable, vertically oriented radiant heat source is shown in Fig. 1. It consists of a bank of five,500 W infrared, tubular, translucent quartz lamps having a 127 mm (5.0-in.) light
35、ed length and a mean overall length of 222 mm(834 in.). The lamps are mounted on 9.5 6 0.4 mm (38 6 164-in.) centers so that the lamp surfaces are approximately 0.4 mm(164-in.) apart. The bank or array of lamps are mounted and centered behind a 63.5 by 140 mm (212 by 512-in.) cut-out that isposition
36、ed in the center of a 12.7 mm (12-in.) thick, 86 mm (338-in.) wide, by 292 mm (11-12 in.) long high temperature insulatingboard as shown in Fig. 2.The quartz lamps are heated electrically, and the power input controlled by means of a rheostat or variablepower supply having a capacity of at least 25A
37、.6.1.1.1 Setting and monitoring the voltmeter readout on a voltage-controlled variable power supply is one method to calibrateand monitor the exposure level during the testing on a system so equipped.Avoltmeter, accurate to6161 V, is typically installedwith the appropriate load circuit to indicate l
38、amp operating power.FIG. 1 General Expanded View of a Compliant Radiant Heat Performance Test Apparatus (see Figs. 2-4 for specific item details)F2702 1536.1.1.2 Any covers or guards installed on the quartz lamp assembly shall be designed such that any convective energy generatedis not allowed to im
39、pinge on the sample specimen (vertical, unimpeded ventilation is required).NOTE 3Radiant measurement systems designed with closed lamp assembly covers and covers with minimal ventilation have been found to exhibitlarge measurement biases in round robin testing.NOTE 4Quartz infrared lamps, part descr
40、iption QH500T3/CL from General Electric Company, Consumer ASTM F18.65.01 Testing Group Report on Arc Testing Analysis of the F1959 Standard Test MethodPhase 1”66.1.5.2 The thermocouple wire is installed in the calorimeter as shown in Fig. 5.(1) The thermocouple wire shall be bonded to the copper dis
41、k either mechanically or by using high melting point (HMP) solder.(2) A mechanical bond shall be produced by mechanically deforming the copper disk material (utilizing a copper filling slugas shown in Fig. 5) around the thermocouple bead.(3) A solder bond shall be produced by using a suitable HMP so
42、lder with a melting temperature 280 C.NOTE 8HMP solders consisting of 5 %Sb-95 %Pb (307C melting point) and 5 %Sb-93.5 %Pb-1.5 %Ag (300C melting point) have been foundto be suitable. The 280Ctemperature minimum identified above corresponds to the point where melting of the solder bond would be exper
43、ienced withan 17 second exposure of an 84 kW/m2 heat flux to a prepared copper calorimeter with a surface area of 12.57 cm2 and a mass of 18.0 g. A carefulsoldering technique is required to avoid “cold” solder joints (where the solder has not formed a suitable bond of the thermocouple to the copper
44、disk).6.1.6 Data Acquisition/Analysis SystemA data acquisition/analysis system is required that is capable of recording thecalorimeter temperature response, calculating the resulting thermal energy, and determining the test endpoint by comparing thetime-dependent thermal energy transfer reading to t
45、he empirical performance curve.6.1.6.1 The data acquisition component must have a minimum sampling rate of four samples per second for temperatures to250C with a minimum resolution of 0.1C and an accuracy of 60.75C. It must be capable of making cold junction correctionsand converting the millivolt t
46、hermocouple signals to temperature (See NIST Monograph 175 or ASTM MNL127 Manual on theUse of Thermocouples in Temperature Measurement).6.1.7 Solvents, alcohol or petroleum solvent for cleaning the copper slug calorimeter.7. Hazards7.1 This test method uses a high radiant energy source to test mater
47、ials. The apparatus shall be adequately shielded to minimizeany radiant exposure to personnel. Avoid viewing the lamps when energized.7.2 Perform the test in an appropriate exhaust hood that is designed to contain and carry away combustion products, smoke, andfumes. Shield the apparatus or turn off
48、the hood while running the test; turn the hood on to clear the fumes. Maintain an adequateseparation between the radiant heat source and combustible materials.7.3 The specimen holder and sensor assembly become heated during prolonged testinguse protective gloves when handlingthese hot objects.7.4 Ob
49、serve the appropriate precautions if a specimen ignites or generates combustible gases. Use only the appropriate firesuppression materials for electrical systems if it becomes necessary to extinguish a fire at the unit.6 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:F18-1001.7 Available from ASTM Headquarters.NOTE 1Secure the copper disk into the supporting insulation board with three sewing pins cut to a nominal 5 mm (0.375 in.) in length positionedaround
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