1、Designation: F 2621 06Standard Practice forDetermining Response Characteristics and Design Integrityof Arc Rated Finished Products in an Electric Arc Exposure1This standard is issued under the fixed designation F 2621; the number immediately following the designation indicates the year oforiginal ad
2、option or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice provides procedural guidelines for con-ducting arc test
3、ing on finished products intended for use asthermal protection by workers who may be exposed to electricarcs.1.1.1 This practice is intended to provide procedural guide-lines to improve consistency across testing groups. Thispractice is not intended to define the end points, parameters, ormeasures t
4、o be studied by the tester.1.1.2 This practice is supplemental to Test Methods F 1959/F 1959M and F 2178. Protective materials used to manufacturearc rated finished products shall be tested according to TestMethod F 1959/F 1959M prior to being tested according to thispractice, and face protective pr
5、oducts shall be tested accordingto Test Method F 2178 prior to being tested according to thispractice. Test Methods F 1959/F 1959M and F 2178 providedefinitive numeric arc ratings for materials intended for use infinished products worn by workers exposed to electric arcs.1.1.2.1 DiscussionFace prote
6、ctive products such as faceshields and hoods are tested as finished products using TestMethod F 2178. These items may be subsequently tested usingthis practice in order to determine the performance of theinterface area between the face protective product and the arcflash PPE worn on the torso.1.1.3
7、The test specimens used in this practice shall be in theform of arc-rated finished products. These arc-rated finishedproducts may include, but are not limited to, single layergarments, multi-layer garments or ensembles, cooling vests,gloves, chaps, rainwear, balaclavas, faceshields, and hoodassembli
8、es with hood shield windows. Non-arc rated finishedproducts shall not be used except that flammable under-layersmay be included when part of a flame resistant system or fordetecting heat transmission level through the finished productand flammable finished products may in some cases beappropriate fo
9、r incident reenactment.1.1.4 The arc rated finished product specimens are newproducts as sold or products which have been used for theintended purpose for a designated time period.1.1.5 Fabrics, fabric layered systems, sewing thread, find-ings and closures used in arc rated finished products testedu
10、nder this practice shall meet the requirements of SpecificationF 1506.1.1.6 Rainwear materials, findings and closures tested underthis practice shall meet the requirements of SpecificationF 1891.1.2 This practice shall be used to measure and describe theresponse characteristics or design integrity o
11、f arc-rated mate-rials, products, or assemblies in the form of finished productswhen exposed to radiant and convective energy generated byan electric arc under controlled laboratory conditions.1.3 This practice can be used to determine the integrity ofclosures and seams, the protective performance o
12、f arc-ratedproducts in areas where garment overlap occurs or whereheraldry is used, and response characteristics such as after-flame time, melting, dripping, deformation, shrinkage, electricarc ignition, or other damage, or combination thereof, offabrics, systems of fabrics, flammable undergarments
13、whenincluded as part of a system, sewing thread, findings andclosures.1.4 This practice can be used to identify the effectiveness offinished product specimens in attenuating heat, sound orpressure waves, or combination thereof.1.5 This practice can be used for incident reenactment,training demonstra
14、tions and material/design comparisons.1.6 The values stated in either SI units or in other units shallbe regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each systemmust be used independently of the other, without combiningvalues in any way.1.
15、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 to an as
16、sessmentof the fire hazard of a particular end use.1.8 This standard does not purport to describe or appraisethe effect of the electric arc fragmentation explosion andsubsequent molten metal splatter, which involves the pressurewave containing molten metals and possible fragments of othermaterials e
17、xcept to the extent that evidence of projectiledamage is assessed and reported, and an optional determination1This practice is under the jurisdiction of ASTM Committee F18 on ElectricalProtective Equipment for Workers and is the direct responsibility of SubcommitteeF18.65 on Wearing Apparel.Current
18、edition approved Nov. 15, 2006. Published December 2006.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.of the attenuation of sound or pressure wave, or both, due to thepresence of the finished product specimen may be reported.1.9 Th
19、is 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 prior to use. For specificprecauti
20、ons, see Section 7.2. Referenced Documents2.1 ASTM Standards:2D 123 Terminology Relating to TextilesD 4391 Terminology Relating to The Burning Behavior ofTextilesF 1494 Terminology Relating to Protective ClothingF 1506 Performance Specification for Flame Resistant Tex-tile Materials for Wearing Appa
21、rel for Use by ElectricalWorkers Exposed to Momentary Electric Arc and RelatedThermal HazardsF 1891 Specification for Arc and Flame Resistant RainwearF 1958/F 1958M Test Method for Determining the Ignit-ability of Non-flame-Resistant Materials for Clothing byElectric Arc Exposure Method Using Manneq
22、uinsF 1959/F 1959M Test Method for Determining the ArcRating of Materials for ClothingF 2178 Test Method for Determining The Arc Rating OfFace Protective Products3. Terminology3.1 For definitions of other textile terms used in thispractice, refer to Terminologies D 123, D 4391 and F 1494.3.2 Definit
23、ions of Terms Specific to This Standard:3.2.1 afterflame, npersistent flaming of a material afterthe ignition source has been removed.3.2.2 afterflame time, nthe length of time for which amaterial continues to flame after the ignition source has beenremoved.3.2.3 arc duration, ntime duration of the
24、arc, s.3.2.4 arc energy, nsum of the instantaneous arc voltagevalues 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 rated finished product, na commercial productused
25、for arc flash protection in the form as it is sold and used.3.2.7 arc rating, nvalue attributed to materials that de-scribes their performance to an exposure to an electric arcdischarge.3.2.7.1 DiscussionThe arc rating is expressed in cal/cm2and is derived from the determined value of ATPV or EBT(sh
26、ould a material system exhibit a breakopen response belowthe ATPV value).3.2.8 arc thermal performance value (ATPV), nin arctesting, the incident energy on a material or multilayer systemof materials that results in a 50 % probability that sufficientheat transfer through the tested specimen is predi
27、cted to causethe onset of a second-degree skin burn injury based on the Stollcurve, cal/cm2.3.2.8.1 DiscussionThe ATPV is determined using TestMethod F 1959/F 1959M.3.2.9 arc voltage, nvoltage across the gap caused by thecurrent flowing through the resistance created by the arc gap(V).3.2.10 asymmet
28、rical arc current, nthe total arc currentproduced during closure; it includes a direct component and asymmetrical component, A.3.2.11 blowout, nthe extinguishing of the arc caused by amagnetic field.3.2.12 breakopen, nin electric arc testing, a materialresponse evidenced by the formation of one or m
29、ore holes inthe material which may allow thermal energy to pass throughmaterial.3.2.12.1 DiscussionThe specimen is considered to exhibitbreakopen when any hole is at least 1.6 cm2(0.5 in.2) in area orat least 2.5 cm (1.0 in.) in any dimension. Single threads acrossthe opening or hole do not reduce t
30、he size of the hole for thepurpose of this practice. In multiple layer finished productspecimens of flame resistant materials, all the layers mustexhibit breakopen in order to meet the definition.3.2.13 breakopen threshold energy (EBT), nthe incidentenergy on a material or system of materials that r
31、esults in a 50% probability of breakopen.3.2.13.1 DiscussionThe EBTis determined using TestMethod F 1959/F 1959M.3.2.14 calorimeter, na device used in which the heatmeasured causes a change in state.3.2.14.1 DiscussionThe determination of heat energy, as aconsequence of an electrical arc exposure, i
32、s made in thisprocedure by measuring the change in temperature of anexposed copper slug of specific geometry and mass duringfinite time intervals.3.2.15 charring, nformation of carbonaceous residue asthe result of pyrolysis or incomplete combustion.3.2.16 closure, nin initiating the arc current with
33、 anelectrical switch, the point on supply current wave from wherearc is initiated.3.2.17 deformation, nfor electric arc testing of finishedproducts, the sagging of material greater than 3 in. or meltingin any manner that the faceshield, hood window or othermelted material touches any part of the bod
34、y.3.2.18 delta peak temperature, ndifference between themaximum temperatures and the initial temperature of thesensor during the test, C.3.2.19 dripping, nin electric arc testing, a material re-sponse evidenced by flowing of a polymer and dropletsseparating from the material.3.2.19.1 DiscussionFor f
35、inished product protective cloth-ing and equipment, dripping can involve the fiber polymer,coatings, findings, the faceshield window material or any othercomponent of the finished product.3.2.20 electric arc ignition, nin electric arc testing of arcrated finished products, the initiation of combusti
36、on as related2For 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 Document Summary page onthe ASTM website.F2621062to electric arc exposure, a response tha
37、t causes the ignition ofthe test specimen material which is accompanied by heat andlight, and then subsequent burning for at least 5 s, andconsumption of at least 25 % of the test specimen area.3.2.20.1 DiscussionFor multilayer specimens, consump-tion of the innermost FR layer must be at least 25 %.
38、3.2.21 garment closure, nin a finished product or gar-ment, the area in which two parts are joined with a mechanicaldevice.3.2.21.1 DiscussionExamples of closures are zippers,snaps, buttons or hook themethods and facilities for garment maintenance; the number oflaunderings or processings the garment
39、s have been subjectedto; and other factors that could impact the protective perfor-mance of different garments. Test results from specific usedgarments should be considered only an approximation ofresults that might be obtained from other used garments of thesame type.5.1.2 Because of the variabilit
40、y of the arc exposure, differ-ent heat transmission values may result for individual sensors.The results of each sensor are evaluated in accordance withSection 12.5.2 This practice maintains the specimen in a static, verticalposition and does not involve movement except that resultingfrom the exposu
41、re.6. Apparatus6.1 General Arrangement for Using Mannequin Torso andHead Sensors and Monitor SensorsThe test apparatus shallconsist of supply bus, arc controller, recorder, arc electrodes asdescribed in Test Methods F 1958/F 1958M and F 2178,atleast one four-sensor mannequin torso as specified in Te
42、stMethod F 1958/F 1958M or at least one four-sensor head asspecified in Test Method F 2178, or both, and at least one setof incident energy monitoring sensors as specified in F 1958/F 1958M or F 2178, or both.6.1.1 Additional sensors can be added to the mannequin onan optional basis.6.1.2 Alower tor
43、so with legs can be added to the mannequinon an optional basis.6.1.3 Modify the vertical position of the electrodes and theelectrode gap on an optional basis in order to create an arcexposure on any area of the mannequin of particular interest.6.1.3.1 For finished products that provide protection to
44、 thetorso, arms and legs but not the head, an area of interest is theclosure area on the mannequin torso.F26210646.1.3.2 For finished products that provide face protectionand protection to the torso, arms and legs, areas of interest arethe interface area between the face protection and upper torsopr
45、otection, the torso closure areas, and the interface areabetween the coat and pant finished products.NOTE 1If additional sensors are used, specify the locations and typesof these additional sensors in the report. If a lower torso with legs is addedto the mannequin, specify this in the report. If the
46、 position of the monitorsensors, the electrodes or the electrode gap is modified relative to TestMethods F 1958/F 1958M or F 2178, specify this in the report.6.1.4 Video CamerasOne or more video cameras shall beused to view the tests. One video camera shall be placed so thatthe front of mannequin ca
47、n be viewed.6.1.5 Mannequin ConstructionThe mannequin torso andhead shall be constructed as specified in Test Methods F 1958/F 1958M and F 2178. If a lower torso and legs are added to themannequin, this shall be constructed from the same non-conductive, heat-resistant material as is described for th
48、emannequin torso in Test Method F 1958/F 1958M.6.2 Sensor Response:6.2.1 The copper slug calorimeter sensor response is con-verted to incident energy of units cal/cm2as described in TestMethod F 1959/F 1959M.6.3 Sensor ConstructionThe sensors, sensor mounts andsensor surface conditioning shall be as
49、 described in TestMethod F 1959/F 1959M.6.4 ElectrodesThe electrode shall be as specified in TestMethod F 2178.6.4.1 Fuse WireThe wire shall be as specified in TestMethod F 2178.6.5 Electric SupplyThe electric supply shall be as speci-fied in Test Method F 2178.6.6 Test Circuit ControlRepeat exposures of the arc cur-rents shall not deviate more than 2 % per test from the selectedtest level. The make switch shall be capable of point on waveclosing within 0.2 cycles from test to test such that the closingangle will produce a symmetrical current wav
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