1、Designation:F252212(Reapproved 2017)Standard Test Method forDetermining the Protective Performance of a ShieldAttached on Live Line Tools or on Racking Rods for ElectricArc Hazards1This standard is issued under the fixed designation F2522;the number immediately following the designation indicates th
2、e year oforiginal adoption 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 test method is used to determine the heat attenua-ti
3、on factor(HAF),the effective heat attenuation factor(EHAF),and the shields mechanical strength(SMS)of a shield attachedon live line tools or racking rods intended for protection ofworkers exposed to electric arcs.1.2 The materials used in this test method of workerprotection are in the form of a shi
4、eld attached on live line toolsor on the racking rods.1.3 The protective shield described in this test method shallbe transparent and shall be easily attached and removed fromlive line tools or from racking rods.1.4 The protective shield described in this test method has24-in.(0.61-m)diameter and ca
5、n be used for most applications,however for special cases,the shield can have different sizes tosuit the protective requirements of the application.1.5 This standard shall be used to measure and describe theproperties of materials,products,or assemblies in response toincident energies(thermal-convec
6、tive,and radiant and pressurewave)generated by an electric arc under controlled laboratoryconditions and does not purport to predict damage from light,resultant pressure impact other than the pressure and thermalaspects measured.1.6 The values stated in inch-pound units are to be regardedas standard
7、.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.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.Howev
8、er,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 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 t
9、heresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.Forspecific precautions,see Section 7.1.9 This international standard was developed in accor-dance with internatio
10、nally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D4391 Terminol
11、ogy Relating to The Burning Behavior ofTextilesF1959/F1959M Test Method for Determining theArc Ratingof Materials for Clothing3.Terminology3.1 Definitions:3.1.1 arc,nconductive path in air for the electric currentcaused by ionization of air between two electrodes.3.1.2 arc duration,ntime duration of
12、 the arc,s.3.1.3 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.3.1.4 arc gap,ndistance between the arc electrodes,cmin.3.1.5 arc voltage,nvoltage across the gap caused by thecur
13、rent flowing through the resistance created by the arc gap,V.See also Terminology D4391.1This test method is under the jurisdiction of ASTM Committee F18 onElectrical Protective Equipment for Workers and is the direct responsibility ofSubcommittee F18.35 on Tools&Equipment.Current edition approved N
14、ov.1,2017.Published December 2017.Originallyapproved in 2005.Last previous edition approved in 2012 as F2522-12.DOI:10.1520/F2522-12R17.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume inform
15、ation,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization esta
16、blished in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 3.1.6 asymmetrical arc current,nthe total arc currentproduced during closure;it includes a direct component and asymmetrical component,A.3.1.7 blowout,nthe extinguishing of the arc caused by amagnetic field.3.1.8 closure,npoint on supply current wave form wherearc is initiated.3.1.9 effective heat attenua