1、Designation: F2178 17F2178 17aStandard 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 specif
3、y 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 kWm2 2 to 600 cal/cm2s. Products are tested as sold.1.2 This test method determines an arc rating for eye or face protective products.
4、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 ANSIZ87.1
5、) 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 te
6、sted 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 the design of face protection products suchas in hood, neck guards, balaclava, sha
7、ll meet the requirements of Specification F1506. When fabrics are designed into theprotection provided for eye or face protective products, the arc rating of fabric system shall be determined first by Test MethodF1959/F1959M.1.3.2 The arc rating of the eye or face protective product which requires f
8、abric to provide protection to the face or head willnot be higher than the lower arc rating of either the fabric system or the shield/visor assembly.1.4 This test method shall be used to measure and describe the properties of materials, products, or assemblies in response toconvective and radiant en
9、ergy 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 stated in SI units shall be regarded as standard except as noted. Within the text, alternate units are shown inbrackets. Th
10、e values stated in each system may not be exact equivalents; therefore, alternate systems must be used independentlyof the other. Combining values from the systems described in the text may result in nonconformance with the method.1.6 This standard does not purport to describe or appraise the effect
11、 of the electric arc fragmentation explosion and subsequentmolten metal splatter, which involves the pressure wave containing molten metals and possible fragments of other materials exceptto the extent that heat energy transmission due to these arc explosion phenomena is reduced by test specimens.1.
12、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 this test may be used as elements of a fire assessment which takes into account all ofthe factors which are pertinent to an as
13、sessment 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 responsibilityof the user of this standard to establish appropriate safety, health, and environmental practices and determine the a
14、pplicability ofregulatory limitations prior to use.For specific precautions, see Section 7.1.9 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards
15、, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.1 This test 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.C
16、urrent edition approved July 1, 2017Sept. 1, 2017. Published August 2017October 2017. Originally approved in 2002. Last previous edition approved in 20122017 asF2178 12.F2178 17. DOI: 10.1520/F2178-17.10.1520/F2178-17A.This document is not an ASTM standard and is intended only to provide the user of
17、 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 recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as pub
18、lished 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 States12. Referenced Documents2.1 ASTM Standards:2C177 Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Prop
19、erties 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 for Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) Calorim
20、eterF1494 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 Related Thermal HazardsF1958/F1958M Test Method for Determining the Ignitabili
21、ty 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 of Electrical and Electronics Terms3ANSI Z87.1-2003 Practice for Occupatio
22、nal 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 Electrical and Electronics Terms.3.2 Definitions of Terms Specific to This St
23、andard: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.3.2.3 arc duration, ntime duration of the arc, s.3.2.4 arc energy, vi dt
24、, 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 rating, nvalue attributed to materials that describes their performance to
25、 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 below the ATPV value).3.2.7 arc thermal performance value (ATPV), nthe i
26、ncident 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/cm2.53.2.8 arc voltage, nvoltage across the gap caused by the current flowi
27、ng 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 extinguishing of the arc caused by a magnetic field.3.2.11 breakopen, nin electric ar
28、c 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 Discussion2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual
29、 Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 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 S
30、tandards Institute (ANSI), 25 W. 43rd St., 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
31、Transfer through Fabrics as Related to Thermal Injury,” TransactionsNew York Academy of Sciences, Vol 33 (7), Nov. 1971,pp. 649-670.F2178 17a2The specimen is considered to exhibit breakopen when any hole in the material or fabric is at least 1.6 cm2 0.5 in.2 in area orat least 2.5 cm 1.0 in. in any
32、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 specimens, if some of the layers are ignitable, breakopen occurswhen these layers are exposed.3.2.12 breakopen threshold energy (EBT),
33、 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 logistic regression analysis representing the energy at which breakopenof the layer occurred.3.2.13 deformation, nfor electric arc te
34、sting 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 body.3.2.14 dripping, nin electric arc testing, a material response evidenced by flowing of a specimens material of composition.3.2.1
35、4.1 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 ignition, nin electric arc testing of eye or face protective products, the initiation of combustion as relatedto electric arc exposure, a re
36、sponse 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 of at least 25 % of the test specimen area.3.2.15.1 DiscussionFor multilayer specimens, consumption of the innermost FR layer must be
37、 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.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
38、 of the instantaneous arc current values squared multiplied 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
39、energy (Ei), nin arc testing, the total incident energy delivered 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 re
40、spective two monitor sensors adjacent to the test specimen.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
41、response evidenced by softening of the material.3.2.23 peak 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 si
42、ze.3.2.26 Stoll curve, nan empirical predicted second-degree skin burn injury model, also commonly referred to as the StollResponse.3.2.27 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
43、 of decay of any DC offset.Alarge X/R ratio corresponds 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 tra
44、nsport response is assessed versus the Stoll curve, an approximate human tissue tolerancepredictive model that projects the onset of a second-degree burn injury.F2178 17a34.1.1 Products are mounted on the standard mannequin head containing copper slug calorimeters inserted in the eyes, mouth,and chi
45、n positions. During this procedure, the amount of heat energy 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 slugcalorim
46、eters. The change in temperature versus time is used, along 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
47、 for this procedure are determined by comparing the amount 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 recor
48、ding the observed effects of the electric arc exposure onthe 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
49、arcs.5.1.1 Because of the variability of the arc exposure, 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
