1、Designation: F1959/F1959M 141Standard Test Method forDetermining the Arc Rating of Materials for Clothing1This standard is issued under the fixed designation F1959/F1959M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of
2、 last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTE“Aerial” was corrected to “areal” in January 2017.1. Scope1.1 This test method is used to measure the arc rating ofmaterials
3、 intended for use as flame resistant clothing forworkers exposed to electric arcs that would generate heat fluxrates from 84 to 25 120 kW/m22 to 600 cal/cm2s.1.2 This test method will measure the arc rating of materialswhich meet the following requirements: less than 150 mm 6in. char length and less
4、 than 2 s afterflame when tested inaccordance with Test Method D6413.1.2.1 It is not the intent of this test method to evaluate nonflame-resistant materials except where used as under layers inmultiple-layer specimens.1.3 The materials used in this test method are in the form offlat specimens.1.4 Th
5、is test method shall be used to measure and describethe properties of materials, products, or assemblies in responseto convective and radiant energy generated by an electric arcunder controlled laboratory conditions.1.5 The values stated in SI units shall be regarded asstandard except as noted. With
6、in the text, alternate units areshown in brackets.The values stated in each system may not beexact equivalents therefore alternate systems must be usedindependently of the other. Combining values from the systemsdescribed in the text may result in nonconformance with themethod.1.6 This test method d
7、oes not apply to electrical contact orelectrical shock hazards.1.7 This standard shall not be used to describe or appraisethe fire hazard or fire risk of materials, products, or assembliesunder actual fire conditions. However, results of this test maybe used as elements of a fire assessment which ta
8、kes intoaccount all of the factors which are pertinent to an assessmentof the fire hazard of a particular end use.1.8 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 s
9、afety and health practices and determine the applica-bility of regulatory requirements prior to use. For specificprecautions, see Section 7.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD4391 Terminology Relating t
10、o The Burning Behavior ofTextilesD6413 Test Method for Flame Resistance of Textiles (Ver-tical Test)E457 Test Method for Measuring Heat-Transfer Rate Usinga Thermal Capacitance (Slug) CalorimeterF1494 Terminology Relating to Protective Clothing2.2 ANSI/IEEE Standard:3Standard Dictionary of Electrica
11、l and Electronics Terms2.3 AATCC Standard:4AATCC Method 135-2001 Dimensional Changes in Auto-matic Home Laundering of Woven and Knit Fabrics3. Terminology3.1 Definitions:3.1.1 ablation, nin electrical arc testing, a physical re-sponse evidenced by significant erosion or the formation of oneor more l
12、arge holes in a layer of a multilayer system.3.1.1.1 DiscussionAny layer in a specimen (other than theinnermost layer) is considered to exhibit ablation when thematerial removal or any hole is at least 16 cm22.5 in.2 in areaor at least 8 cm 3.1 in. in length in any dimension. Singlethreads across th
13、e opening or hole do not reduce the size of the1This test method is under the jurisdiction of ASTM Committee F18 onElectrical Protective Equipment for Workers and is the direct responsibility ofSubcommittee F18.65 on Wearing Apparel.Current edition approved April 1, 2014. Published April 2014. Origi
14、nallyapproved in 1997. Last previous edition approved in 2013 as F1959/F1959M 13.DOI: 10.1520/F1959_F1959M-14E01.2For 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
15、 standards Document Summary page onthe ASTM website.3Available from Institute of Electrical and Electronics Engineers, Inc. (IEEE),445 Hoes Ln., P.O. Box 1331, Piscataway, NJ 08854-1331.4Technical Manual of the American Association of Textile Chemists andColorists.Copyright ASTM International, 100 B
16、arr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Reco
17、mmendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1hole for the purposes of this test method. Ablation in one ormore layers of material in a mulitlayer system may removeenergy from the specimen. (See 11.2.7.)3.1.2 ablation response energy (Eab), nthe inci
18、dent energyon a multilayer system that results in a 50 % probability of thephysical response of ablation.3.1.3 arc duration, ntime duration of the arc, s.3.1.4 arc energy, vi dt, nsum of the instantaneous arcvoltage values multiplied by the instantaneous arc currentvalues multiplied by the increment
19、al time values during thearc, J.3.1.5 arc gap, ndistance between the arc electrodes, cmin.3.1.6 arc rating, nvalue attributed to materials that de-scribes their performance to exposure to an electrical arcdischarge.3.1.6.1 DiscussionThe arc rating is expressed in cal/cm2and is derived from the deter
20、mined value of ATPV orEBT(should a material system exhibit a breakopen responsebelow the ATPV value) derived from the determined value ofATPV or EBT(should a material system exhibit a breakopenresponse below the ATPV value).3.1.7 arc thermal performance value (ATPV), nthe inci-dent energy on a mater
21、ial or a multilayer system of materialsthat results in a 50 % probability that sufficient heat transferthrough the tested specimen is predicted to cause the onset ofa second-degree skin burn injury based on the Stoll5curve,kW/m2cal/cm2.3.1.8 arc voltage, nvoltage across the gap caused by thecurrent
22、flowing through the resistance created by the arc gap,V.3.1.9 asymmetrical arc current, nthe total arc currentproduced during closure; it includes a direct component and asymmetrical component, A.3.1.10 blowout, nthe extinguishing of the arc caused by amagnetic field.3.1.11 breakopen, nin electric a
23、rc testing, a materialresponse evidenced by the formation of one or more holes inthe material which may allow thermal energy to pass throughthe material.3.1.11.1 DiscussionThe specimen is considered to exhibitbreakopen when any hole is at least 1.6 cm20.5 in.2 in areaor at least 2.5 cm 1.0 in. in an
24、y dimension. Single threadsacross the opening or hole do not reduce the size of the hole forthe purposes of this test method. In multiple layer specimens offlame resistant material, all the layers must breakopen to meetthe definition. In multiple layer specimens, if some of thelayers are ignitable,
25、breakopen occurs when these layers areexposed.3.1.12 breakopen threshold energy (EBT),nthe incidentenergy on a material or material system that results in a 50 %probability of breakopen.3.1.12.1 DiscussionThis is the value in J/cm2calcm2determined by use of logistic regression analysis representingt
26、he energy at which breakopen of the layer occurred.3.1.13 charring, nthe formation of carbonaceous residueas the result of pyrolysis or incomplete combustion.3.1.14 dripping, nin testing flame-resistant clothing,amaterial response evidenced by flowing of a specimensmaterial of composition.3.1.15 emb
27、rittlement, nthe formation of a brittle residueas the result of pyrolysis or incomplete combustion.3.1.16 heat attenuation factor, HAF, n in electric arctesting, the percent of the incident energy that is blocked by amaterial at an incident energy level equal to ATPV.3.1.17 heatflux, nthe thermal in
28、tensity indicated by theamount of energy transmitted divided by area and timekW/m2calcm2s.3.1.18 i2t, nsum of the instantaneous arc current valuessquared multiplied by the incremental time values during thearc, A2/s.3.1.19 ignitability, n (ignitable, adj)in electric arcexposure, the property of a ma
29、terial involving ignition accom-panied by heat and light, and continued burning resulting inconsumption of at least 25 % of the exposed area of the testspecimen.3.1.20 ignition, nthe initiation of combustion.3.1.21 ignition50,nthe incident energy on a fabric ormaterial that results in a 50 % probabi
30、lity that sufficient heattransfer through the tested specimen is predicted to causeignition of a flammable underlayer.3.1.22 incident energy monitoring sensors, nsensorsmounted on each side of the panel, using the calorimetersdescribed in 6.3, not covered by test material, used to measureincident en
31、ergy.3.1.23 incident energy (Ei), nthe total heat energy re-ceived at the surface of the panel as a direct result of an electricarc.3.1.24 material response, nmaterial response to an elec-tric arc is indicated by the following terms: breakopen, melting,dripping, charring, embrittlement, shrinkage, a
32、nd ignition.3.1.25 melting, nin testing flame resistant clothing,amaterial response evidenced by softening of the material.3.1.26 mix zone, nin arc testing, the range of incidentenergies, which can result in either a positive or negativeoutcome for predicted second-degree burn injury, breakopen orun
33、derlayer ignition. The low value of the range begins with thelowest incident energy indicating a positive result, and the highvalue or the range is the highest incident energy indicating anegative result.3.1.26.1 DiscussionA mix zone is established when thehighest incident energy with a negative res
34、ult is greater thanthe lowest incident energy with a positive result.5Derived from: Stoll,A. M. and Chianta, M.A., “Method and Rating System forEvaluations of Thermal Protection,” Aerospace Medicine , Vol 40, 1969, pp.1232-1238 and Stoll, A. M. and Chianta, M. A., “Heat Transfer through Fabrics asRe
35、lated to Thermal Injury,” TransactionsNew York Academy of Sciences, Vol 33(7), Nov. 1971, pp. 649-670.F1959/F1959M 14123.1.27 peak arc current, nmaximum value of the AC arccurrent, A.3.1.28 RMS arc current, nroot mean square of the AC arccurrent, A.3.1.29 shrinkage, nin testing flame resistant cloth
36、ing,amaterial response evidenced by reduction in specimen size.3.1.30 Stoll curve5, nan empirical predicted second-degree skin burn injury model, also commonly referred to asthe Stoll Response.3.1.31 X/R ratiothe ratio of system inductive reactance toresistance. It is proportional to the L/R ratio o
37、f time constant,and is, therefore, indicative of the rate of decay of any DCoffset. A large X/R ratio corresponds to a large time constantand a slow rate of decay.3.2 For definitions of other textile terms used in this testmethod, refer to Terminologies D123, D4391, and F1494.4. Summary of Test Meth
38、od4.1 This test method determines the heat transport responsethrough a material, fabric, or fabric system when exposed tothe heat energy from an electric arc. This heat transportresponse is assessed versus the Stoll curve, an approximatehuman tissue tolerance predictive model that projects the onset
39、of a second-degree burn injury.4.1.1 During this procedure, the amount of heat energytransferred by the tested material is measured during and afterexposure to an electric arc.4.1.1.1 The thermal energy exposure and heat transportresponse of test specimens are measured with copper slugcalorimeters.
40、The change in temperature versus time is used,along with the known thermo-physical properties of copper todetermine the respective heat energies delivered to and throughthe specimens.4.2 Material performance for this procedure is determinedfrom the amount of heat transferred by and through the teste
41、dmaterial.4.3 Heat transfer data determined by this test method is thebasis of the arc rating for the material.4.3.1 The arc rating determined by this test method is theamount of energy that predicts a 50 % probability of second-degree burn as determined by the Stoll Curve or breakopen(should the sp
42、ecimen exhibit breakopen before the skin burninjury prediction is reached.4.4 Material response shall be further described by record-ing the observed effects of the electric arc exposure on thespecimens using the terms in 12.6.5. Significance and Use5.1 This test method is intended for the determina
43、tion of thearc rating of a material, or a combination of materials.5.1.1 Because of the variability of the arc exposure, differ-ent heat transmission values may be observed at individualsensors. Evaluate the results of each sensor in accordance withSection 12.5.2 This test method maintains the speci
44、men in a static,vertical position and does not involve movement except thatresulting from the exposure.5.3 This test method specifies a standard set of exposureconditions. Different exposure conditions may produce differ-ent results. In addition to the standard set of exposureconditions, other condi
45、tions representative of the expectedhazard may be used and shall be documented in the reportingof the testing results.6. Apparatus6.1 General Arrangement For Determining Arc Rating Us-ing Three Two-Sensor Panels and Monitor SensorsThe testapparatus shall consist of supply bus, arc controller, record
46、er,arc electrodes, three two-sensor panels, and monitor sensors.6.1.1 Arrangement of the Two-Sensor PanelsThree two-sensor panels shall be used for each test and be spaced equallyas shown in Fig. 1. Each two-sensor panel shall have twomonitoring sensors. One monitoring sensor shall be positionedon e
47、ach side of the two-sensor panel as shown in Fig. 2.6.1.1.1 Monitor sensors located at a radius different fromthe two-sensor panels shall be employed when the incidentenergy from the arc exposure results in monitor sensor tem-perature values that exceed the maximum allowed operatingcharacteristic of
48、 the copper calorimeter. See 11.1.1. Monitorsensors shall be positioned whereby there is a clear, unob-structed path between the sensors and the arc electrodecenterline.6.1.2 Panel ConstructionEach two-sensor panel and eachmonitor sensor holder shall be constructed from non-conductive heat resistant
49、 material with a thermal conductivityvalue of 0.9.The paintedsensor shall be dried before use and present a uniformlyapplied coating (no visual thick spots or surface irregularities).Note that an external heat source, for example, an external heatlamp, may be required to completely drive off any remainingorganic carriers in a freshly painted surface.6.2.2.1 DiscussionAn evaluation of the emissivity of thepainted calorimeters used in this test method is available fromASTM; “ASTM Research Program on Electric Arc Test
