1、Designation: F1959/F1959M 14Standard 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.1. Scope1.1 This test method is used to measure the arc rating ofmaterials intended for use as flame resistant clothing forworkers
3、 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 than 2 s afterflame when tested inaccordance with Test
4、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 This test method shall be used to measure and describethe
5、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. Within the text, alternate units areshown in brackets.The va
6、lues 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 does not apply to electrical contact orelectrical shock h
7、azards.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 takes intoaccount all of the factors which are pertinent t
8、o 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 safety and health practices and determine the applica-bil
9、ity 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 to The Burning Behavior ofTextilesD6413 Test Method for F
10、lame 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 Electrical and Electronics Terms2.3 AATCC Standard:4AATCC Method
11、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 large holes in a layer of a multilayer system.3.1.1.1 Dis
12、cussionAny 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 the opening or hole do not reduce the size of thehole for
13、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.)1This test method is under the jurisdiction of ASTM Committee F18 onElectrical Protective Equipment for Workers and is the direct responsibility ofSubco
14、mmittee F18.65 on Wearing Apparel.Current edition approved April 1, 2014. Published April 2014. Originallyapproved in 1997. Last previous edition approved in 2013 as F1959/F1959M 13.DOI: 10.1520/F1959_F1959M-14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cust
15、omer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the 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 Manua
16、l of the American Association of Textile Chemists andColorists.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.2 ablation response energy (Eab), nthe incident energyon a multilayer system that results in a 50 % probability of thep
17、hysical 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 incremental time values during thearc, J.3.1.5 arc gap, ndistance between the arc ele
18、ctrodes, 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 determined value of ATPV orEBT(should a material system exhibit a breakopen respo
19、nsebelow 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 material or a multilayer system of materialsthat results in a 50 % probability th
20、at 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 flowing through the resistance created by the arc gap,V.3.1.9 asymmetrical a
21、rc 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 arc testing, a materialresponse evidenced by the formation of one or more hol
22、es 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 any dimension. Single threadsacross the opening or hole do not reduce the size
23、 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, breakopen occurs when these layers areexposed.3.1.12 breakopen threshold ene
24、rgy (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/cm2cal/cm2determined by use of logistic regression analysis representingthe energy at which breakopen of the layer occurred.3.1.13 charring, nthe fo
25、rmation 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 embrittlement, nthe formation of a brittle residueas the result of pyrolysis o
26、r 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 intensity indicated by theamount of energy transmitted divided by area and ti
27、mekW/m2cal/cm2s.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 material involving ignition accom-panied by heat and light, and continued bu
28、rning 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 % probability that sufficient heattransfer through the tested specimen is predicted
29、 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 energy.3.1.23 incident energy (Ei),nthe total heat energy re-ceived at the s
30、urface 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, and ignition.3.1.25 melting, nin testing flame resistant clothing,amaterial
31、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 orunderlayer ignition. The low value of the range begins with thelowest inciden
32、t 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 result is greater thanthe lowest incident energy with a positive result.3.1.27
33、 peak arc current, nmaximum value of the AC arccurrent, A.3.1.28 RMS arc current, nroot mean square of the AC arccurrent, A.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.
34、and Chianta, M. A., “Heat Transfer through Fabrics asRelated to Thermal Injury,” TransactionsNew York Academy of Sciences, Vol 33(7), Nov. 1971, pp. 649-670.F1959/F1959M 1423.1.29 shrinkage, nin testing flame resistant clothing,amaterial response evidenced by reduction in specimen size.3.1.30 Stoll
35、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 of time constant,and is, therefore, indicative of the rate of decay of any DC
36、offset. 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 Method4.1 This test method determines the heat transport responsethrough a mater
37、ial, 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 onsetof a second-degree burn injury.4.1.1 During this procedure, the amount of he
38、at 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. The change in temperature versus time is used,along with the known thermo-ph
39、ysical 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 testedmaterial.4.3 Heat transfer data determined by this test method is thebasis
40、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 specimen exhibit breakopen before the skin burninjury prediction is reached.4.
41、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 determination of thearc rating of a material, or a combination of materials.5.1.1 Bec
42、ause 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 specimen in a static,vertical position and does not involve movement except thatr
43、esulting 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 conditions representative of the expectedhazard may be used and shall be document
44、ed 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, recorder,arc electrodes, three two-sensor panels, and monitor sensors.6.1.1 Arrang
45、ement 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 each side of the two-sensor panel as shown in Fig. 2.6.1.1.1 Monitor sensors
46、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 the copper calorimeter. See 11.1.1. Monitorsensors shall be positioned wher
47、eby 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 material with a thermal conductivityvalue of 0.9.The paintedsensor shall be
48、 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 eva
49、luation of the emissivity of thepainted calorimeters used in this test method is available fromASTM; “ASTM Research Program on Electric Arc TestMethod Development to Evaluate Protective Clothing Fabric;ASTM F18.65.01 Testing Group Report onArc TestingAnaly-sis of the F1959 Standard Test MethodPhase 1.”6.2.3 The thermocouple wire is installed in the calorimeteras shown in Fig. 6.6.2.4 Alternate calorimeters are permitted for use as moni-tor sensors provided they are calibrated and have a similarresponse to those in 6.2.1
