ASTM F2621-2012 Standard Practice for Determining Response Characteristics and Design Integrity of Arc Rated Finished Products in an Electric Arc Exposure《测定电弧辐照中电弧额定成品响应特性和设计完整性的标.pdf

1、Designation: F2621 12Standard Practice forDetermining Response Characteristics and Design Integrityof Arc Rated Finished Products in an Electric Arc Exposure1This standard is issued under the fixed designation F2621; the number immediately following the designation indicates the year oforiginal adop

2、tion or, in the 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 practice provides procedural guidelines for con-ducting arc testing

3、 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 to b

4、e studied by the tester.1.1.2 This practice is supplemental to Test Methods F1959/F1959M and F2178. Protective materials used to manufacturearc rated finished products shall be tested according to TestMethod F1959/F1959M prior to being tested according to thispractice, and face protective products s

5、hall be tested accordingto Test Method F2178 prior to being tested according to thispractice. Test Methods F1959/F1959M and F2178 providedefinitive numeric arc ratings for materials intended for use infinished products worn by workers exposed to electric arcs.1.1.2.1 DiscussionFace protective produc

6、ts such as faceshields and hoods are tested as finished products using TestMethod F2178. 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 The test spec

7、imens 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 hoodassemblies with hood

8、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 for incident re

9、enactment.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 testedunder this pra

10、ctice shall meet the requirements of SpecificationF1506.1.1.6 Rainwear materials, findings and closures tested underthis practice shall meet the requirements of SpecificationF1891.1.2 This practice shall be used to measure and describe theresponse characteristics or design integrity of arc-ratedmate

11、rials, products, or assemblies in the form of finishedproducts when exposed to radiant and convective energygenerated by an electric arc under controlled laboratory con-ditions.1.3 This practice can be used to determine the integrity ofclosures and seams, the protective performance of arc-ratedprodu

12、cts 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 whenincluded as

13、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 demonstrations and materi

14、al/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.1.7 This standard

15、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 assessmentof the f

16、ire hazard of a particular end use.1This 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 edition approved Oct. 1, 2012. Published November 2012. Originallyapproved

17、 in 2006. Last previous edition approved in 2006 as F2621-06. DOI:10.1520/F2621-12.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States11.8 This standard does not purport to describe or appraisethe effect of the electric arc fragmentation

18、explosion andsubsequent molten metal splatter, which involves the pressurewave containing molten metals and possible fragments of othermaterials except to the extent that evidence of projectiledamage is assessed and reported, and an optional determinationof the attenuation of sound or pressure wave,

19、 or both, due to thepresence of the finished product specimen may be reported.1.9 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 deter

20、mine the applica-bility of regulatory limitations prior to use. For specificprecautions, see Section 7.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD4391 Terminology Relating to The Burning Behavior ofTextilesF1494 Terminology Relating to Protective ClothingF1506 P

21、erformance Specification for Flame Resistant andArc Rated Textile Materials for Wearing Apparel for Useby Electrical Workers Exposed to Momentary ElectricArcand Related Thermal HazardsF1891 Specification for Arc and Flame Resistant RainwearF1958/F1958M Test Method for Determining the Ignitabil-ity o

22、f Non-flame-Resistant Materials for Clothing byElectric Arc Exposure Method Using MannequinsF1959/F1959M Test Method for Determining theArc Ratingof Materials for ClothingF2178 Test Method for Determining the Arc Rating andStandard Specification for Eye or Face Protective Prod-ucts3. Terminology3.1

23、For definitions of other textile terms used in thispractice, refer to Terminologies D123, D4391 and F1494.3.2 Definitions of Terms Specific to This Standard:3.2.1 afterflame, npersistent flaming of a material after theignition source has been removed.3.2.2 afterflame time, nthe length of time for wh

24、ich amaterial continues to flame after the ignition source has beenremoved.3.2.3 arc duration, ntime duration of the 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.

25、5 arc gap, ndistance between the arc electrodes, cm(in.).3.2.6 arc rated finished product, na commercial productused 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 arcdischar

26、ge.3.2.7.1 DiscussionThe arc rating is expressed in cal/cm2and is derived from the determined value of ATPV or EBT(should a material system exhibit a breakopen response belowthe ATPV value).3.2.8 arc thermal performance value (ATPV), nthe inci-dent energy on a material or multilayer system of materi

27、als thatresults 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 Stoll curve,kW/m2cal/cm2.3.2.8.1 DiscussionThe ATPV is determined using TestMethod F1959/F1959M.3.2.9 arc voltage, nvoltage a

28、cross the gap caused by thecurrent flowing through the resistance created by the arc gap(V).3.2.10 asymmetrical 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 f

29、ield.3.2.12 breakopen, nin electric arc testing , a materialresponse evidenced by the formation of one or more 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

30、area orat least 2.5 cm (1.0 in.) in any dimension. Single threads acrossthe opening or hole do not reduce the 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 definiti

31、on.3.2.13 breakopen threshold energy (EBT),nthe incidentenergy on a material or system of materials that results in a 50% probability of breakopen.3.2.13.1 DiscussionThe EBTis determined using TestMethod F1959/F1959M.3.2.14 calorimeter, na device used in which the heatmeasured causes a change in sta

32、te.3.2.14.1 DiscussionThe determination of heat energy, as aconsequence of an electrical arc exposure, is 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 residu

33、e asthe result of pyrolysis or incomplete combustion.3.2.16 closure, nthe point on supply current wave fromwhere arc 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

34、othermelted material touches any part of the body.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 standards Document Summary page onthe ASTM website.F2621 1223.

35、2.18 dripping, nin electric arc testing , a materialresponse evidenced by flowing of a polymer and dropletsseparating from the material.3.2.18.1 DiscussionFor finished product protective cloth-ing and equipment, dripping can involve the fiber polymer,coatings, findings, the faceshield window materia

36、l or any othercomponent of the finished product.3.2.19 electric arc ignition, nin electric arc testing of arcrated finished products, the initiation of combustion as relatedto electric arc exposure, a response that causes the ignition ofthe test specimen material which is accompanied by heat andligh

37、t, and then subsequent burning for at least 5 s, andconsumption of at least 25 % of the test specimen area.3.2.19.1 DiscussionFor multilayer specimens, consump-tion of the innermost FR layer must be at least 25 %.3.2.20 garment closure, nin a finished product orgarment, the area in which two parts a

38、re joined with amechanical device.3.2.20.1 DiscussionExamples of closures are zippers,snaps, buttons or hook themethods and facilities for garment maintenance; the number oflaunderings or processings the garments have been subjectedto; and other factors that could impact the protective perfor-mance

39、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 variability of the arc exposure, differ-ent heat transmission values may result for individual sens

40、ors.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 exposure.6. Apparatus6.1 General Arrangement for Using Mannequin Torso andHead Sensors and Moni

41、tor SensorsThe test apparatus shallconsist of supply bus, arc controller, recorder, arc electrodes asdescribed in Test Methods F1958/F1958M and F2178, at leastone four-sensor mannequin torso as specified in Test MethodF1958/F1958M or at least one four-sensor head as specified inTest Method F2178, or

42、 both, and at least one set of incidentenergy monitoring sensors as specified in F1958/F1958M orF2178, or both.6.1.1 Additional sensors can be added to the mannequin onan optional basis.F2621 1246.1.2 Alower torso with legs can be added to the mannequinon an optional basis.6.1.3 Modify the vertical

43、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 thetorso, arms and legs but not the head, an area of interest is theclosure area on the

44、mannequin torso.6.1.3.2 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 torsoprotection, the torso closure areas, and the interface areabetween the coat and pant finished produ

45、cts.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 position of the monitorsensors, the electrodes or the electrode gap is modified relative to Test

46、Methods F1958/F1958M or F2178, 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 can be viewed.6.1.5 Mannequin ConstructionThe mannequin torso andhead shall be constructed as specifie

47、d in Test Methods F1958/F1958M and F2178. 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 themannequin torso in Test Method F1958/F1958M.6.2 Sensor Response:6.2.1 The copper slug calorimeter sens

48、or response is con-verted to incident energy of units cal/cm2as described in TestMethod F1959/F1959M.6.3 Sensor ConstructionThe sensors, sensor mounts andsensor surface conditioning shall be as described in TestMethod F1959/F1959M.6.4 ElectrodesThe electrode shall be as specified in TestMethod F2178

49、.6.4.1 Fuse WireThe wire shall be as specified in TestMethod F2178.6.5 Electric Supply The electric supply shall be as speci-fied in Test Method F2178.6.6 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 wave repeatable fromtest to test. The arc current, duration, and voltage shall bemeasured. The arc current, dur