1、Designation: F2703 08 (Reapproved 2013)Standard Test Method forUnsteady-State Heat Transfer Evaluation of Flame ResistantMaterials for Clothing with Burn Injury Prediction1This standard is issued under the fixed designation F2703; the number immediately following the designation indicates the year o
2、foriginal 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 measures the non-steady state heattransfe
3、r through flame resistant materials for clothing subjectedto a combined convective and radiant heat exposure.1.1.1 This test method is not applicable to materials that arenot flame resistant.NOTE 1The determination of a materials flame resistance shall bemade prior to testing and done in accordance
4、with the applicableperformance or specification standard, or both, for the materials end-use.1.1.2 This test method accounts for the thermal energycontained in an exposed test specimen after the standardizedcombined convective and radiant heat exposure has ceased andis used to estimate performance t
5、o a predicted second-degreeskin burn injury.1.2 This test method is used to measure and describe theresponse of materials, products, or assemblies to heat undercontrolled conditions, but does not by itself incorporate allfactors required for fire hazard or fire risk assessment of thematerials, produ
6、cts, or assemblies under actual fire conditions.1.3 The values stated in SI units are to be regarded asstandard. The values given in parentheses are mathematicalconversions to inch-pound or other units that are commonlyused for thermal testing.1.4 This standard does not purport to address the safety
7、concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1
8、776 Practice for Conditioning and Testing TextilesD1777 Test Method for Thickness of Textile MaterialsD3776 Test Methods for Mass Per Unit Area (Weight) ofFabricE457 Test Method for Measuring Heat-Transfer Rate Usinga Thermal Capacitance (Slug) CalorimeterF1494 Terminology Relating to Protective Clo
9、thing3. Terminology3.1 Definitions:3.1.1 breakopen, nin testing thermal protective materials,a material response evidenced by the formation of a hole in thetest specimen during the thermal exposure that may result inthe exposure energy in direct contact with the heat sensor.3.1.1.1 DiscussionThe spe
10、cimen is considered to exhibitbreakopen when a hole is produced as a result of the thermalexposure that is at least 3.2 cm2(0.5 in.2) in area or at least 2.5cm (1.0 in.) in any dimension. Single threads across theopening or hole do not reduce the size of the hole for thepurposes of this test method.
11、3.1.2 charring, nthe formation of a carbonaceous residueas the result of pyrolysis or incomplete combustion.3.1.3 dripping, na material response evidenced by flowingof the polymer.3.1.4 embrittlement, nthe formation of a brittle residue asa result of pyrolysis or incomplete combustion.3.1.5 heat flu
12、x, nthe thermal intensity indicated by theamount of energy transmitted divided by area and time; kW/m2(cal/cm2s).3.1.6 ignition, nthe initiation of combustion.3.1.7 melting, na material response evidenced by soften-ing of the polymer.3.1.8 unsteady state heat transfer value, nin testing ofthermal pr
13、otective materials, a quantity expressed as thetime-dependent difference between the incident and exitingthermal energy values normal to and across two definedparallel surfaces of an exposed thermal insulative material.3.1.9 thermal performance estimate (TPE), nin testing ofthermal protective materi
14、als, the cumulative amount of energyidentified by the intersection of a measured time-dependent1This test method is under the jurisdiction ofASTM Committee F23 on PersonalProtective Clothing and Equipment and is the direct responsibility of SubcommitteeF23.80 on Flame and Thermal.Current edition app
15、roved June 1, 2013. Published June 2013. Originallyapproved in 2008. Last previous edition approved in 2008 as F2703 - 08. DOI:10.1520/F2703-08R13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandard
16、s volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1heat transfer response through a subject material to a time-dependent, empirical predicted second-de
17、gree skin burn injuryperformance curve3, expressed as a rating or value; J/cm2(cal/cm2).3.1.10 response to heat exposure, nin testing the resis-tance to heat transfer of thermal protective materials, theobservable response of the material to the energy exposure asindicated by break-open, melting, dr
18、ipping, charring,embrittlement, shrinkage, sticking, and ignition.3.1.11 second-degree burn injury, nin testing of thermalprotective materials, reversible burn damage at the epidermis/dermis interface in human tissue.3.1.12 shrinkage, na decrease in one or more dimensionsof an object or material.3.1
19、.13 sticking, na material response evidenced by soft-ening and adherence of the material to the surface of itself oranother material.3.1.14 sample test suite, nany number of test specimensused to derive a single thermal performance estimate value.3.1.14.1 Discussionthe determination of a single ther
20、malperformance estimate value requires exposing a number ofspecimens under varying exposure conditions so that thethermal energy stored in the sample after the heat source isremoved is considered and accounted for when determiningperformance against a burn injury prediction.3.1.15 For the definition
21、s of protective clothing terms usedin this method, refer to Terminology F1494, and for othertextile terms used in this method, refer to Terminology D123.4. Summary of Test Method4.1 A horizontally positioned test specimen is exposed to acombined convective and radiant heat source with an exposurehea
22、t flux of 84 6 2kW/m2(2 6 0.05 cal/cm2s).NOTE 2Other exposure heat flux values are allowed, howeverdifferent exposure conditions have the potential to produce differentresults. The test facility shall verify the stability of other exposure levelsover the materials exposure time interval (used to det
23、ermine the thermalperformance estimate value) and include this in the test results report.4.2 The unsteady-state transfer of heat through the testspecimen is measured using a copper slug calorimeter. Thechange in temperature versus time is used, along with theknown thermo-physical properties of copp
24、er, to determine therespective thermal energy passed through the test specimen.4.3 A Thermal Performance Estimate value of the testspecimen is determined iteratively as the intersection of thetime-dependent cumulative heat response as measured by thecalorimeter to a time-dependent, empirical predict
25、ed second-degree skin burn injury performance curve identified in10.4.1.5, Eq 1).4.4 Observations of the thermal response of the specimenresulting from the exposure are optionally reported.5. Significance and Use5.1 This test method is intended for the determination of athermal performance estimate
26、value of a material, a combina-tion of materials, or a comparison of different materials used inflame resistant clothing for workers exposed to combinedconvective and radiant thermal hazards.5.2 This test method evaluates a materials heat transferproperties when exposed to a heat exposure at a const
27、ant valueand specific duration. Air movement at the face of thespecimen and around the calorimeter can affect the measuredheat transferred due to forced convective heat losses. Minimiz-ing air movement around the specimen and test apparatus willaid in the repeatability of the results.5.3 This test m
28、ethod accounts for the thermal energy storedin the exposed test specimen after the heat exposure hasceased. Higher values of Thermal Performance Estimate rat-ings determined in this test associate to higher values ofthermal (convective and radiative) energy protection against apredicted skin burn in
29、jury.5.4 This test method maintains the specimen in a static,horizontal position and does not involve movement except thatresulting from the exposure.5.5 This test method specifies a standardized 84 6 2kW/m2(2 6 0.05 cal/cm2s) exposure condition. Different exposureconditions have the potential to pr
30、oduce different results. Otherexposure conditions representative of the expected hazard areallowed but shall be reported with the results along with adetermination of the exposure energy level stability.5.6 This test method contains optional provisions for con-ducting certification testing against a
31、 prescribed ThermalPerformance Estimate value.6. Apparatus and Materials6.1 General ArrangementThe measurement apparatusconfiguration consists of a combined convective and radiantenergy heat source, a water cooled shutter for exposure control,a specimen and sensor support structure, a specimen holde
32、rassembly, a copper calorimeter sensor assembly, and a dataacquisition/analysis system. Automation of the apparatus forexecution of the measurement procedure is allowed. Thegeneral arrangement of the test apparatus configuration isshown in Fig. 1.6.2 Gas SupplyPropane (commercial grade or better) or
33、Methane (technical grade or better).6.3 Gas FlowmeterAny gas flowmeter or rotometer withrange to give a flow equivalent of at least 6 L (0.21 ft3)/min airat standard conditions.6.4 Thermal Energy Source6.4.1 Two each, Meker or Fisher burners jetted for theselected fuel gas (propane or methane) with
34、a 38 mm (1.5 in.)diameter top arranged so that the bodies (top section) do notobstruct the quartz lamps and their flame profiles overlap.Dimension tolerances are 65%.3Derived from: Stoll, A.M. and Chianta, M.A., “Method and Rating System forEvaluations of Thermal Protection”, Aerospace Medicine, Vol
35、 40, 1969, pp.1232-1238 and Stoll, A.M. and Chianta, M.A., “Heat Transfer through Fabrics asRelated to Thermal Injury”, Transactions New York Academy of Sciences, Vol 33(7), Nov. 1971, pp. 649-670.F2703 08 (2013)26.4.2 Nine 500W T3 translucent quartz infrared lamps4,connected to a variable electrica
36、l power controller, arranged asa linear array with 13 6 0.5 mm center-to-center spacing set125 6 10 mm from the specimen surface.6.4.2.1 Use of a water-cooled housing for the quartz infra-red lamp bank is recommended. This helps to avoid heatingadjacent mechanical components and to shield the operat
37、orfrom the radiant energy.6.5 Thermal Sensor6.5.1 The transmitted heat sensor is a 4 6 0.05 cm diametercircular copper slug calorimeter5constructed from electricalgrade copper with a mass of 18 6 0.05 g (prior to drilling) witha singleANSI type J (Fe/Cu-Ni) orANSI type K (Ni-Cr/Ni-Al)thermocouple wi
38、re bead (0.254 mm wire diameter or finerequivalent to 30 AWG) installed as identified in 6.5.2 andshown in Fig. 2. The sensor holder shall be constructed fromnon-conductive heat resistant material with a thermal conduc-tivity value of 0.15 W/mK, high temperature stability, andresistance to thermal s
39、hock. The board shall be nominally 1.3cm (0.5 in.) or greater in thickness. The sensor is held into therecess of the board using three straight pins, trimmed to anominal length of 5 mm, by placing them equidistant aroundthe edge of the sensor so that the heads of the pins hold thesensor flush to the
40、 surface.6.5.1.1 Paint the exposed surface of the copper slug calo-rimeter with a thin coating of a flat black high temperaturespray paint with an absorptivity of 0.9 or greater6. The paintedsensor must be dried and cured, in accordance with themanufacturers instructions, before use and present a un
41、iformlyapplied coating (no visual thick spots or surface irregularities).In the absence of manufacturers instructions, an external heatsource, for example, an external heat lamp, shall be used tocompletely drive off any remaining organic carriers in a freshlypainted surface before use.NOTE 3Emissivi
42、ty of painted calorimeters is discussed in the ASTMReport, “ASTM Research Program on Electric Arc Test Method Devel-opment to Evaluate Protective Clothing Fabric; ASTM F18.65.01 TestingGroup Report on Arc Testing Analysis of the F1959 Standard TestMethodPhase 1”76.5.2 The thermocouple wire bead is i
43、nstalled in the calo-rimeter as shown in Fig. 2.6.5.2.1 The thermocouple wire bead shall be bonded to thecopper disk either mechanically or by using high melting point(HMP) solder.(1) A mechanical bond shall be produced by mechanicallydeforming the copper disk material (utilizing a copper fillingslu
44、g as shown in Fig. 2) around the thermocouple bead.(2) A solder bond shall be produced by using a suitableHMP solder with a melting temperature 280C.NOTE 4HMP solders consisting of 5 %Sb-95 %Pb (307C meltingpoint) and 5 %Sb-93.5 %Pb-1.5 %Ag (;300C melting point) have beenfound to be suitable. The 28
45、0C temperature minimum identified abovecorresponds to the point where melting of the solder bond would beexperienced with an 17 second exposure of an 84 kW/m2heat flux to aprepared copper calorimeter with a surface area of 12.57 cm2and a massof 18.0 g. A careful soldering technique is required to av
46、oid “cold” solderjoints (where the solder has not formed a suitable bond of the thermo-couple to the copper disk).6.5.3 Weight the sensor board assembly so that the totalmass is 1.0 6 0.01 kg and the downward force exhibited by thecopper slug sensor surface is uniform.NOTE 5Any system of weighting t
47、hat provides a uniformly weightedsensor is allowed.An auxiliary stainless steel plate affixed to or individualweights placed at the top of the sensor assembly, or both have been foundto be effective.6.6 Data Acquisition/Analysis SystemA data acquisition/analysis system is required that is capable of
48、 recording the4A500 Watt T3 120VAC quartz infrared heat lamp, product number 21651-1from Philips Lighting Company has been used successfully in this application.5See Test Method E457 for information regarding slug calorimeters.6Zynolyte #635 from Aervoe Industries has been found suitable. Zynolyte i
49、s aregistered trademark of the Glidden Company.7Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:F18-1001.NOTE 1Note the exposure heat source incorporates two Meker burners and nine quartz infrared lampsFIG. 1 Apparatus used to Measure Heat Transfer Performance of Textile MaterialsF2703 08 (2013)3calorimeter temperature response, calculating the resultingthermal energy, and determining the test endpoint by compar-ing the time-dependent thermal energy transfer reading to
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