1、Designation: F2178 12F2178 17Standard Test Method forDetermining the Arc Rating and Standard Specification forEye or Face Protective Products1This standard is issued under the fixed designation F2178; 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 and product specification is used to measure the arc rating and specify
3、 the requirements for productsintended for use as eye or face protection for workers exposed to electric arcs that would generate heat flux values from 84 to25 120 kW/mkWm2 2 to 600 cal/cm2s. Products are tested as sold.1.2 This test method determines an arc rating for eye or face protective product
4、s. The faceshield, safety spectacle, goggle or orother applicable portions of the complete product must meet ANSI Z87.1. This excludes the textile or non ANSI Z87.1 testableparts of the hood assemblies or other tested products. This standard does not measure optical and impact properties (see ANSIZ8
5、7.1) but does specify requirements for optical and impact properties.1.3 The materials covered by this standard are in the form of faceshields attached to the head by protective helmets (hard hats),headgear, hood assemblies, safety spectacles or goggles. Faceshields, safety spectacles or goggles are
6、 tested with or without otherface and head protective products, for example, sock hoods, balaclavas, sweat shirt hoods or jacket hoods.1.3.1 Fabric layers used in hood assemblies or other items tested under this standard shall meet the requirements of SpecificationF1506.1.4 This test method shall be
7、 used to measure and describe the properties of materials, products, or assemblies in response toconvective and radiant energy generated by an electric arc under controlled laboratory conditions and does not purport to predictdamage from light other than the thermal aspects measured.1.5 The values s
8、tated in SI units shall be regarded as standard except as noted. Within the text, alternate units are shown inbrackets.The values stated in each system may nonot be exact equivalents; therefore, alternate systems must be used independentlyof the other. Combining values from the systems described in
9、the text may result in nonconformance with the method.1.6 This standard does not purport to describe or appraise the effect of the electric arc fragmentation explosion and subsequentmolten metal splatter, which involves the pressure wave containing molten metals and possible fragments of other mater
10、ials exceptto the extent that heat energy transmission due to these arc explosion phenomena is reduced by test specimens.1.7 This standard shall not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies underactual fire conditions. However, results of thi
11、s test may be used as elements of a fire assessment which takes into account all ofthe factors which are pertinent to an assessment of the fire hazard of a particular end use.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsi
12、bilityof the user of this standard to establish appropriate safety safety, health and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.For specific precautions, see Section 7.1.9 This international standard was developed in accordance with internati
13、onally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:21 This test
14、 method is under the jurisdiction of ASTM Committee F18 on Electrical Protective Equipment for Workers and is the direct responsibility of SubcommitteeF18.65 on Wearing Apparel.Current edition approved Oct. 1, 2012July 1, 2017. Published November 2012August 2017. Originally approved in 2002. Last pr
15、evious edition approved in 20082012 asF2178 08.F2178 12. DOI: 10.1520/F2178-12.10.1520/F2178-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Documen
16、t 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 indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM reco
17、mmends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1C177 Test Met
18、hod for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of theGuarded-Hot-Plate ApparatusD123 Terminology Relating to TextilesD3776 Test Methods for Mass Per Unit Area (Weight) of FabricD4391 Terminology Relating to The Burning Behavior of TextilesE457 Test Method fo
19、r Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) CalorimeterF1494 Terminology Relating to Protective ClothingF1506 Performance Specification for Flame Resistant andArc Rated Textile Materials for WearingApparel for Use by ElectricalWorkers Exposed to Momentary Electric Arc and Relat
20、ed Thermal HazardsF1958/F1958M Test Method for Determining the Ignitability of Non-flame-Resistant Materials for Clothing by Electric ArcExposure Method Using MannequinsF1959/F1959M Test Method for Determining the Arc Rating of Materials for Clothing2.2 ANSI/IEEE Standards:IEEE Standard Dictionary o
21、f Electrical and Electronics Terms3ANSI Z87.1-2003 Practice for Occupational and Educational Eye and Face Protection43. Terminology3.1 DefinitionsFor definitions of other textile terms used in this method, refer to terminology in Terminology D123, D4391,F1494 and the IEEE Standard Dictionary of Elec
22、trical and Electronics Terms.3.2 Definitions of Terms Specific to This Standard:3.2.1 afterflame, npersistent flaming of a material after the ignition source has been removed.3.2.2 afterflame time, nthe length of time for which a material continues to flame after the ignition source has been removed
23、.3.2.3 arc duration, ntime duration of the arc, s.3.2.4 arc energy, vi dt, nsum of the instantaneous arc voltage values multiplied by the instantaneous arc current valuesmultiplied by the incremental time values during the arc, J.3.2.5 arc gap, ndistance between the arc electrodes, cm in.3.2.6 arc r
24、ating, nvalue attributed to materials that describes their performance to exposure to an electric arc discharge,J/cm2 (calcm2).3.2.6.1 DiscussionThe arc rating is expressed in J/cm2 (calcm2) and is derived from the determined value of ATPV or EBT (should a material systemexhibit a breakopen response
25、 below the ATPV value).3.2.7 arc thermal performance value (ATPV), nthe incident energy of a fabric or material that results in 50 % probability thatsufficient heat transfer through the specimen is predicted to cause the onset of a second-degree skin burn injury based on the Stollcurve, kW/m2 cal/cm
26、2.53.2.8 arc voltage, nvoltage across the gap caused by the current flowing through the resistance created by the arc gap (V).3.2.9 asymmetrical arc current, nthe total arc current produced during closure; it includes a direct component and asymmetrical component, A.3.2.10 blowout, nthe extinguishin
27、g of the arc caused by a magnetic field.3.2.11 breakopen, nin electric arc testing, a material response evidenced by the formation of one or more holes in the materialwhich may allow thermal energy to pass through material.3.2.11.1 DiscussionThe specimen is considered to exhibit breakopen when any h
28、ole in the material or fabric is at least 1.6 cm2 0.5 in.2 in area or3 Available from Institute of Electrical and Electronics Engineers, Inc. (IEEE), 445 Hoes Ln., P.O. Box 1331, Piscataway, NJ 08854-1331, http:/www.ieee.org.4 Available from American National Standards Institute (ANSI), 25 W. 43rd S
29、t., 4th Floor, New York, NY 10036, http:/www.ansi.org.5 Derived from Stoll, A. M., and Chianta, M. A., “Method and Rating System for Evaluations of Thermal Protection,” Aerospace Medicine , Vol 40, 1969, pp. 1232-1238and Stoll, A. M., and Chianta, M. A., “Heat Transfer through Fabrics as Related to
30、Thermal Injury,” TransactionsNew York Academy of Sciences, Vol 33 (7), Nov. 1971,pp. 649-670.F2178 172at least 2.5 cm 1.0 in. in any dimension. For textile materials, single threads across the opening or hole do not reduce the sizeof the hole for the purposes of this test method. In multiple layer s
31、pecimens, if some of the layers are ignitable, breakopen occurswhen these layers are exposed.3.2.12 breakopen threshold energy (EBT), nthe incident energy on a fabric or material that results in a 50 % probability ofbreakopen.3.2.12.1 DiscussionThis is the value in J/cm2 calcm2 determined by use of
32、logistic regression analysis representing the energy at which breakopenof the layer occurred.3.2.13 deformation, nfor electric arc testing of eye or face protective products, the sagging of material greater than 7.6 cm3 in. or melting in any manner that the faceshield/window touches any part of the
33、body.3.2.14 dripping, nin electric arc testing, a material response evidenced by flowing of a specimens material of composition.3.2.14.1 DiscussionDripping is exhibited by either the fabric material or faceshield material, or other parts of eye or face protective products.3.2.15 electric arc ignitio
34、n, nin electric arc testing of eye or face protective products, the initiation of combustion as relatedto electric arc exposure, a response that causes the ignition of textile test specimen material which is accompanied by heat and light,and then subsequent burning for at least 5 s, and consumption
35、of at least 25 % of the test specimen area.3.2.15.1 DiscussionFor multilayer specimens, consumption of the innermost FR layer must be at least 25 %.3.2.16 faceshield, na protective device commonly intended to shield the wearers face, or portions thereof, in addition to theeyes, from certain hazards.
36、3.2.17 heat attenuation factor, HAF, nin electric arc testing, the average of the percent of the incident energy that is blockedby a material.3.2.17.1 DiscussionIn arc testing of eye or face protective products,HAF (face) is based on the highest sensor reading among the four head sensorsfor each hea
37、d exposure. HAF (eye) is based on the highest sensor reading among the two eye sensors for each head exposure.3.2.17 heat flux, nthe thermal intensity indicated by the amount of energy transmitted per area and time W/m2 calcm2s.3.2.18 i2t,nsum of the instantaneous arc current values squared multipli
38、ed by the incremental time values during the arc,A2/s.3.2.19 incident energy monitoring sensors, nsensors mounted on each side of each head, using calorimeters, not covered byspecimens, used to measure incident energy.3.2.20 incident exposure energy (Ei), nin arc testing, the total incident energy d
39、elivered to monitor calorimeter sensors as aresult of the arc exposure, J/cm2 calcm 2.3.2.20.1 DiscussionIn an arc test exposure, incident exposure energy for a specimen is determined from the average of the measured incident energyfrom the respective two monitor sensors adjacent to the test specime
40、n.3.2.21 material response, nmaterial response to an electric arc is indicated by the following terms: breakopen, melting,dripping, deformation, afterflame time, shrinkage, and electric arc ignition.3.2.22 melting, nin arc testing, a material response evidenced by softening of the material.3.2.23 pe
41、ak arc current, nmaximum value of the AC arc current, A.3.2.24 RMS arc current, nroot mean square of the AC arc current, A.3.2.25 shrinkage, nin testing eye or face protective products, a material response evidenced by reduction in specimen size.3.2.26 Stoll curve, nan empirical predicted second-deg
42、ree skin burn injury model, also commonly referred to as the StollResponse.F2178 1733.2.27 X/R ratio, nthe ratio of system inductive reactance to resistance. It is proportional to the L/R ratio of time constant,and is, therefore, indicative of the rate of decay of any DC offset.Alarge X/R ratio corr
43、esponds to a large time constant and a slowrate of decay.4. Summary of Test Method4.1 This test method determines the heat transport response across a material, fabric, or fabric system when exposed to the heatenergy from an electric arc. This heat transport response is assessed versus the Stoll cur
44、ve, an approximate human tissue tolerancepredictive model that projects the onset of a second-degree burn injury.4.1.1 Products are mounted on the standard mannequin head containing copper slug calorimeters inserted in the eyes, mouth,and chin positions. During this procedure, the amount of heat ene
45、rgy transferred by the specimen eye or face protective productsis measured during and after exposure to an electric arc.4.1.2 The thermal energy exposure and heat transport response of the test specimen(s) are measured with copper slugcalorimeters. The change in temperature versus time is used, alon
46、g with the known thermo-physical properties of copper todetermine the respective thermal energies delivered to and through the specimen(s).4.2 This procedure incorporates incident energy monitoring sensors.4.3 Product and material performance for this procedure are determined by comparing the amount
47、 of thermal energy generatedby the arc flash on monitor sensors with the energy transferred by or through the test specimen(s) and measured by sensors on themannequin head.4.4 Product and material responses shall be further described by recording the observed effects of the electric arc exposure ont
48、he specimens using the terms in the Report section.5. Significance and Use5.1 This test method is intended for the determination of the arc rating of a product/design, intended for use as eye or faceprotection for workers exposed to electric arcs.5.1.1 Because of the variability of the arc exposure,
49、 different heat transmission values may be observed at individual sensors.The results of each sensor are evaluated in accordance with Section 12.5.2 This test method maintains the specimen in a static, vertical position and does not involve movement except that resultingfrom the exposure.5.3 This test method specifies a standard set of exposure conditions. Different exposure conditions may produce different results.5.4 This specification covers the minimum performance criteria for arc resistance and other requir
copyright@ 2008-2019 麦多课文库（www.mydoc123.com）网站版权所有
备案/许可证编号：苏ICP备17064731号-1