1、Designation: F2731 11Standard Test Method forMeasuring the Transmitted and Stored Energy of FirefighterProtective Clothing Systems1This standard is issued under the fixed designation F2731; the number immediately following the designation indicates the year oforiginal adoption or, in the case of rev
2、ision, 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 provides procedures for measuring thecombination of transmitted and stored energy
3、that occurs infirefighter protective clothing material systems as the result ofexposure to prolonged, relatively low levels of radiant heat.1.1.1 This test method applies a predetermined compressiveload to a preheated specimen to simulate conductive heattransfer.1.1.2 This test method is not applica
4、ble to protective cloth-ing systems that are not flame resistant.1.1.3 DiscussionFlame resistance of the material systemshall be determined prior to testing according to the applicableperformance and/or specification standard for the materialsend-use.1.2 This test method establishes procedures for m
5、oisturepreconditioning of firefighter protective clothing material sys-tems.1.3 The second-degree burn injury used in this standard isbased on a limited number of experiments on forearms ofhuman subjects.1.3.1 DiscussionThe length of exposures needed to gen-erate a second-degree burn injury in this
6、test method exceedsthe exposures times found in the limited number of experi-ments on human forearms.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are mathematicalconversions to English units or other units commonly used forthermal testing.1.5 T
7、his standard is used to measure and describe theproperties of materials, products, or assemblies in response toradiant heat under controlled laboratory conditions but doesnot by itself incorporate all factors required for fire-hazard orfire-risk assessment of the materials, products, or assembliesun
8、der actual fire conditions.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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations p
9、rior to use. Specific precau-tionary information is found in Section 7.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1777 Test Method for Thickness of Textile MaterialsD3776 Test Methods for Mass Per Unit Area (Weight) ofFabricF1494 Terminology Relating to Protecti
10、ve ClothingF1930 Test Method for Evaluation of Flame ResistantClothing for Protection Against Flash Fire SimulationsUsing an Instrumented Manikin2.2 AATCC Test Methods:3AATCC 70 Test Method for Water Repellency: Tumble JarDynamic Absorption TestAATCC 135 Dimensional Changes in Automatic HomeLaunderi
11、ng of Durable Press Woven or Knit Fabrics2.3 NFPA Standard:4NFPA 1971 Standard on Protective Ensembles for Struc-tural Fire Fighting and Proximity Fire Fighting3. Terminology3.1 Definitions:3.1.1 break-open, nin testing thermal protective materi-als, a material response evidence by the formation of
12、a hole inthe test specimen.3.1.1.1 DiscussionThe specimen is considered to exhibitbreak-open when a hole is produced as a result of the thermalexposure that is at least 3.2 cm2(0.25 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
13、 size of the hole for purposesof this test method.1This 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 approved July 1, 2011. Published July 2011. Orig
14、inally approvedin 2010. Last previous edition approved in 2010 as F2731 - 10. DOI: 10.1520/F2731-11.2For 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 Do
15、cument Summary page onthe ASTM website.3Available from American Association of Textile Chemists and Colorists(AATCC), P.O. Box 12215, Research Triangle Park, NC 27709, http:/www.aatcc.org.4Available from National Fire Protection Association (NFPA), 1 BatterymarchPark, Quincy, MA 02169-7471, http:/ww
16、w.nfpa.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.2 charring, nthe formation a carbonaceous residue asthe result of pyrolysis or incomplete combustion.3.1.3 dripping, na material response evidenced by flow-ing of the pol
17、ymer.3.1.4 embrittlement, nthe formation of brittle residue as aresult of pyrolysis or incomplete combustion.3.1.5 heat flux, nthe thermal intensity indicated by theamount of energy transmitted per unit area and per unit time;kW/m2(cal/cm2-s).3.1.6 ignition, nthe initiation of combustion.3.1.7 melti
18、ng, nin testing thermal protective materials, aresponse evidenced by softening of the polymer.3.1.8 response to heat exposure, nin testing for thetransmitted and stored energy of thermal protective materials,the observable response of the textile to the energy exposure asindicated by break-open, mel
19、ting, dripping, charring, em-brittlement, shrinkage, sticking, and ignition.3.1.8.1 DiscussionFor the purposes of this test method,response to heat exposure also includes any non-textile rein-forcement material used as part of the protective clothingmaterial system that is tested.3.1.9 second-degree
20、 burn injury, nreversible burn dam-age in the epidermis and upper layers of the dermis, resultingin blistering, severe pain, reddening, and swelling.3.1.10 shrinkage, na decrease in one or more dimensionsof an object or material.3.1.11 sticking, na response evidenced by softening andadherence of the
21、 material to other material.3.1.11.1 DiscussionFor the purpose of this test method,the observation of sticking applies to any material layer in theprotective clothing material system.3.1.12 stored energy, nin testing thermal protective ma-terials, thermal energy that remains in a fabric/composite af
22、terthe heating source is removed.3.1.12.1 DiscussionThe stored energy measured by thisstandard only accounts for the energy released to the sensorafter compressing. Stored energy is also lost to the compressorblock and the surrounding environment.3.1.13 thermal protective clothing system, nany combi
23、na-tion of materials which when used as a composite can limit therate of heat transfer to or from the wearer of the clothing.3.1.13.1 DiscussionThe rate at which this heat transferoccurs can vary depending on the materials.3.2 For definitions of other terms used in this test method,refer to Terminol
24、ogy D123 and Terminology F1494.4. Summary of Test Method4.1 A vertically positioned test specimen, representative ofthe lay-up in firefighter protective clothing, is exposed to arelatively low level of radiant heat flux at 8.5 6 0.5 kW/m2(0.26 0.012 cal/cm2-s) for a fixed period of time.4.2 During t
25、he time of radiant heat exposure, a data collec-tion sensor, positioned 6.4 6 0.1 mm (0.25 6 0.004 in.) behindand parallel to the innermost surface of the test specimen,measures the heat energy transmitted through the test speci-men.4.3 In the same test apparatus, the test specimen is com-pressed ag
26、ainst the data collection sensor at a pressure of 13.86 0.7 kPa (2.0 psi 6 0.1 psi) for a fixed period of time. Thisload could possibly simulate a firefighter leaning against awall, squatting or sitting down. This compression step occursafter the fixed radiant heat exposure time and after thespecime
27、n is moved away from the heating source.4.4 During the time of compression against the data collec-tion sensor, the data collection sensor continues to measure theheat energy transferred from the test specimen for a fixedduration of time.4.5 The total energy transmitted and stored by the testspecime
28、n is used to predict whether a second degree burninjury can be predicted. If a second-degree burn injury ispredicted, the time to a second degree burn injury is reported.4.6 Two different sets of procedures are provided. In Pro-cedure A, an iterative method is used to determine theminimum length of
29、the radiant heat exposure followed by a 60second compression that will result in the prediction of asecond degree burn injury. In Procedure B, testing is conductedat fixed radiant heat exposure and a 60-second compressionperiod. The report for Procedure B includes if a second degreeburn injury has b
30、een predicted and if predicted, the time for asecond degree burn injury.4.7 If a second degree burn injury is not predicted, the resultis indicated as “no predicted burn.”4.8 Appendix X1 contains a general description of humanburn injury, its calculation and historical notes.5. Significance and Use5
31、.1 Firefighters are routinely exposed to radiant heat in thecourse of their fireground activities. In some cases, firefightershave reported burn injuries under clothing where there is noevidence of damage to the exterior or interior layers of thefirefighter protective clothing.5Low levels of transmi
32、ttedradiant energy alone or a combination of the transmittedradiant energy and stored energy released through compressioncan be sufficient to cause these types of injuries. This testmethod was designed to measure both the transmitted andstored energy in firefighter protective clothing material syste
33、msunder a specific set of laboratory exposure conditions.5.2 The intensity of radiant heat exposure used in this testmethod was chosen to be an approximate midpoint represen-tative of ordinary fireground conditions as defined for struc-tural firefighting (1), (2)6. The specific radiant heat exposure
34、was selected at 8.5 6 0.5 kW/m2(0.20 6 0.012 cal/cm2-s)since this level of radiant heat can be maintained by the testequipment and produces little or no damage to mostNFPA 1971 compliant protective clothing systems.5.2.1 DiscussionUtech defined ordinary fireground con-ditions as having air temperatu
35、res ranging from 60 to 300Cand having heat flux values ranging from 2.1 to 21.0 kW/m2(0.05 to 0.5 cal/cm2-s).5.3 Protective clothing systems include the materials used inthe composite structure. These include the outer shell, moisture5Development of a Test Method for Measuring Transmitted Heat and S
36、toredThermal Energy in Firefighter Turnouts, final report presented to National Institutefor Occupational Safety and Health (NIOSH) National Personal Protective Tech-nology Laboratory (NPPTL) under Contract No. 200-2005-12411, April 29, 2008.6The boldface numbers in parentheses refer to a list of re
37、ferences at the end ofthis standard.F2731 112barrier, and thermal barrier. It is possible they will also includeother materials used on firefighter protective clothing such asreinforcement layers, seams, pockets, flaps, hook and loop,straps, or reflective trim.5.4 The transmission and storage of hea
38、t energy in fire-fighter protective clothing is affected by several factors. Theseinclude the effects of “wear” and “use” conditions of theprotective clothing system. In this test method, conditioningprocedures are provided for the laundering of compositesamples prior to testing, and also composite
39、sample moisturepreconditioning. The amount of moisture added during precon-ditioning typically falls into a worst case amount in terms ofpredicted heat transfer, as suggested by Barker (3).5.5 Two different procedures for conducting the test areprovided in this test method. Procedure A involves an i
40、terativeapproach to determine the minimum exposure time followedby a fixed 60-second compression time required to predict asecond degree burn injury. In this approach, the length of theradiant exposure is varied systematically using a series of teststo determine the length of the radiant exposure th
41、at will resultin the prediction of a second degree burn injury. Procedure Binvolves using a fixed radiant heat exposure time to determineif a second degree burn injury will or will not be predicted. Ifa second degree burn injury is predicted, the time to a seconddegree burn injury is reported. If a
42、second degree burn injuryis not predicted, the result is indicated as “no predicted burn.”Procedure B involves a fewer number of tests. This procedureincludes recommended fixed radiant exposure times.6. Apparatus and Materials6.1 General ArrangementThe transmitted and stored en-ergy testing apparatu
43、s shall consist of a specimen holder,sensor assembly, transfer tray, data collection sensor, compres-sor assembly, heating source, and a data acquisition/controls/burn damage analysis system. A overhead view of thesecomponents, minus the data acquisition/controls/ burn damageanalysis system, is illu
44、strated in Fig. 1.6.2 Specimen HolderThe specimen holder shall consist ofupper and lower mounting plates made of stainless steel. Eachplate shall be 170 by 170 6 1 mm (6.6 by 6.6 6 0.04 in.) andthe thickness shall be 6.4 6 0.1 mm (0.25 6 0.004 in.), witha centered 100 by 100 6 1 mm (3.9 by 3.9 6 0.0
45、4 in.) hole.The lower plate shall have an attached handle that is at least 75mm (3 in.) in length. The lower specimen mounting plate shallhave a minimum of two alignment posts attached perpendicularto the plane of the plate. The upper sample mounting plate shallhave corresponding holes on each side
46、so that the upperspecimen mounting plate fits over the lower specimen mount-ing plate. The specimen holder components are shown in Fig.2.6.2.1 The handle of the sample holder shall be made of orsurrounded by a material with a low thermal conductivity.6.2.2 The alignment posts shall be positioned suc
47、h that theydo not interfere with the test specimen.6.3 Sensor AssemblyThe sensor assembly shall be com-posed of a water cooled plate and a sensor holder.6.3.1 The water cooled plate is constructed from a 3.2 61-mm thick copper sheet with 3.2 6 1-mm outer diametercopper tubing soldered to the back si
48、de. The copper plate shallbe machined at its centerline to accept the data collectionsensor with a tolerance of +0.3 mm. The four corners of theplate shall be drilled to accept a countersunk screw.6.3.1.1 The copper tubing shall be looped back and forthacross the back side of the copper plate to pro
49、vide a uniformtemperature across the surface of the copper plate.6.3.1.2 Water shall flow through the copper tubing at a rateof no less than 100 mL/min and the water shall have atemperature be 32.5 6 1C.6.3.2 DiscussionThe 32.5C temperature was set basedon the average surface temperature of the forearms of volun-teers as measured by Pennes (4).6.3.2.1 The exposed surface of water cooled plate shall bepainted with a thin coating of flat black high temperature spraypaint with an emissivity of 0.9 or greater. The painted water-cooled plate shall be dried be
