1、Designation: E1725 141An American National StandardStandard Test Methods forFire Tests of Fire-Resistive Barrier Systems for ElectricalSystem Components1This standard is issued under the fixed designation E1725; the number immediately following the designation indicates the year oforiginal adoption
2、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.1NOTESections were rearranged editorially in December 2016.1. Scope*1.1 These test method
3、s cover fire-test-response.1.2 These fire-test-response test methods provide informa-tion on the temperatures recorded on the electrical systemcomponent within a fire-resistive barrier system during theperiod of exposure.1.3 This standard is used to measure and describe theresponse of materials, pro
4、ducts, or assemblies to heat andflame under controlled conditions, but does not by itselfincorporate all factors required for fire hazard or fire riskassessment of the materials, products, or assemblies underactual fire conditions.1.4 Potentially important factors and fire characteristics notaddress
5、ed by these test methods include, but are not limited to:1.4.1 The performance of the fire-resistive barrier systemconstructed with components other than those tested.1.4.2 An evaluation of the functionality of the electricalsystem within the fire-resistive barrier system.1.4.3 An evaluation of the
6、ampacity of the electrical systemwithin the fire-resistive barrier system.1.4.4 An evaluation of the smoke, toxic gases, corrosivity,or other products of heating.1.4.5 A measurement of the flame spread characteristicsover the surface of the fire-resistive barrier system.1.4.6 An evaluation of throug
7、h-penetration sealing methods.1.4.7 Combustibility of materials in the fire-resistive barriersystem or of the electrical system components.1.4.8 The need for supports beyond those normally re-quired.1.4.9 Environmental conditions in the area of service.1.5 The values stated in inch-pound units are t
8、o be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of
9、 the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.7 Fire testing is inherently hazardous. Adequate safe-guards for personnel and property shall be employed inconducting these tests.2. Referenced
10、Documents2.1 ASTM Standards:2E119 Test Methods for Fire Tests of Building Constructionand MaterialsE1529 Test Methods for Determining Effects of Large Hy-drocarbon Pool Fires on Structural Members and Assem-blies3. Terminology3.1 Definitions:3.1.1 air droplengths of open run conductors or cablessupp
11、orted only at each end.3.1.2 electrical system componentscable trays, conduitsand other raceways, open run cables and conductors, cables,conductors, cabinets, and other components, as defined or usedin the National Electrical Code, and air drops as defined in3.1.1.3.1.3 fire-resistive barrier system
12、a specific construction ofdevices, materials, or coatings installed around, or applied to,the electrical system components.3.1.4 specimena construction consisting of electrical sys-tem components and a fire-resistive barrier system.1These test methods are under the jurisdiction of ASTM Committee E05
13、 on FireStandards and are the direct responsibility of Subcommittee E05.11 on FireResistance.Current edition approved July 1, 2014. Published August 2014. Originallyapproved in 1995. Last previous edition approved in 2008 as E172508. DOI:10.1520/E1725-14E01.2For referenced ASTM standards, visit the
14、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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr
15、 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recomme
16、ndations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.13.1.5 test assemblyhorizontal or vertical construction onwhich test specimens are to be mounted together with associ-ated instrumentation.4. Significance and Use4.1 These fire-test-response test methods eval
17、uate, under thespecified test conditions, the ability of a fire-resistive barriersystem to inhibit thermal transmission to the electrical systemcomponent within.4.2 In these procedures, the specimens are subjected to oneor more specific sets of laboratory test conditions. If differenttest conditions
18、 are substituted or the end-use conditions arechanged, it is not always possible by or from these test methodsto predict changes in the fire test response characteristicsmeasured. Therefore, the results are valid only for the fire testexposure conditions described in these procedures.4.3 These test
19、methods provide a measurement of thetransmission of heat to the electrical system components withinthe barrier system.4.4 These test methods provide qualification of a fireresis-tive barrier system as one element of an electrical systemdesigned to maintain continuous operation of critical functionsa
20、nd processes for a specific fire resistance rating.4.4.1 In addition to the temperature data provided by thesetest methods, numerous other factors, such as referenced in 1.4shall be considered in specifying such a system.5. Control of Fire Test5.1 Fire Test Exposure Conditions:5.1.1 Time-Temperature
21、 CurveMaintain the fire environ-ment within the furnace in accordance with the standardtime-temperature curve shown in Test Method E119 or therapid temperature rise curve shown in Test Method E1529.5.2 Furnace Temperatures:5.2.1 The temperature fixed by the curve shall be theaverage temperature obta
22、ined from readings of thermocouplesdistributed within the test furnace. Disperse the thermocouplesas symmetrically as possible within the furnace to measure thetemperature near all exterior surfaces of the specimen. Do notplace the thermocouples at locations where temperature read-ings would be effe
23、cted by drafts within the furnace.5.2.2 Measure and report the temperatures at intervals notexceeding 1 min.5.3 Furnace Thermocouples:5.3.1 Test Method E119:5.3.1.1 Enclose the thermocouples in sealed protectiontubes of such materials and dimensions that the time constantof the protected thermocoupl
24、e assembly lies within the rangefrom 300 to 400 s3. The exposed length of the pyrometer tubeand thermocouple in the furnace chamber shall be not less than12 in. (305 mm).5.3.2 Test Methods E1529:5.3.2.1 Measure the temperature of the gases adjacent to andimpinging on the test specimens using factory
25、 manufactured0.25-in. (6-mm) outside diameter (OD), Inconel-sheathed,Type K, chromel-alumel thermocouples. The time constant, inair, of the thermocouple assemblies shall be less than 60 s. Usestandard calibration thermocouples with an accuracy of60.75 %. A minimum length of 20 diameters (125 mm) of
26、thesheathed junction end of the thermocouple shall be mountedparallel to the surface of the test specimen.5.4 Furnace Thermocouple LocationsPosition the furnacecontrol thermocouples before the start of the fire exposure test.It shall be permitted to move the thermocouple to avoidtouching the specime
27、n as a result of its deflection during thetest.5.4.1 Place the junction of each thermocouple 12 6 1 in.(305 6 25 mm) from the surface of horizontal constructions or12 6 1 in. from the surface of specimens mounted in horizontalconstructions.5.4.2 Place the junction of each thermocouple 6 6 1 in. (152
28、6 25 mm) from the surface of vertical constructions or 6 6 1in. from the surface of specimens mounted in vertical construc-tions.5.4.3 Use a minimum of three thermocouples.5.4.3.1 For specimens mounted in horizontal constructions,there shall be no less than five thermocouples per 100 ft2(9 m2)of exp
29、osed area. Calculate the exposed area to be the sum ofthe exterior surface area of the fire-resistive barrier system plusthe area of the horizontal construction exposed to the furnacefire.5.4.3.2 For specimens mounted in vertical constructions,there shall be no less than nine thermocouples per 100 f
30、t2(9m2) of exposed area. Calculate the exposed area to be the sumof the exterior surface area of the fire resistive barrier systemplus the area of the vertical construction exposed to the furnacefire.5.5 Furnace Control:5.5.1 Test Method E119 Time-Temperature Curve:5.5.1.1 The control of the furnace
31、 control shall be such thatthe area under the time-temperature curve, obtained by aver-aging the results from the furnace thermocouple readings, is3A typical thermocouple meeting these time-constant requirements may befabricated by fusion-welding the twisted ends of No. 18 B that is, each side rail
32、equals one set, one bareNo. 8 AWG equals one set.7.3 Temperature measurements are allowed to be made atlocations in addition to those described in 7.1 for the purposeof providing additional information on the performance of thefire-resistive barrier system.7.4 Measure temperatures on the surfaces of
33、 the compo-nents with thermojunctions screwed, riveted, welded, orpeened to the surface. The thermocouple leads shall be nolarger than No. 24 AWG and electrically insulated with heat-and moisture-resistive coverings capable of withstanding aminimum single-exposure temperature of 600F (316C).7.5 Meas
34、ure temperatures on the bare No. 8 AWG strandedcopper wire with thermojunction placed in direct contact withthe copper wire. Attach the thermocouples mechanically to thebare No. 8 AWG stranded copper wire.4The thermocoupleleads shall be no larger than No. 24 AWG and electricallyinsulated with heat-
35、and moisture-resistive coverings capableof withstanding a minimum single-exposure temperature of600F (316C).NOTE 1PTFE-insulated thermocouple wire has been found suitablefor this purpose.8. Calibration and Standardization8.1 Furnace Calibration:8.1.1 Test Method E119 does not contain a calibrationpr
36、ocedure.4Buchanan Splice Caps No. 2006S, crimped with a Buchanan C-24 pres-SURE-tool have been found suitable for this purpose (Buchanan Construction Products,Inc., Hackettstown, NJ 07840). The cylindrical splice caps are constructed of thincopper and result in a very secure and robust attachment wi
37、th the addition of aminimal thermal mass.FIG. 6 Vertical and Horizontal Air Drop AssemblyE1725 14178.1.2 Test Method E1529 contains a calibration procedure,that is described in the following sections.8.1.2.1 Expose the test specimen to heat flux and tempera-ture conditions representative of total co
38、ntinuous engulfment inthe luminous flame regime of a large free-burning fluid-hydrocarbon-fueled pool fire. Use calibration assemblies todemonstrate that the required heat flux and temperature levelsare generated in the fire test facility.8.1.2.2 Measure the total heat flux using a circular foil hea
39、tflux gage (often called a Gardon gage after the developer).8.1.2.3 The test setup will provide an average total cold wallheat flux on all exposed surfaces of the test specimen of 50 000FIG. 7 Specimen ThermocouplesE1725 14186 2500 Btu/ft2h (158 6 8kW/m2). The total cold wall heatflux can be control
40、led by varying the flow of fuel and air.Attainthe cold heat flux of 50 000 Btu/ft2h within the first 5 min ofthe test exposure; maintain this heat flux for the duration of thetest.8.1.2.4 The temperature of the environment that generatesthe heat flux of 50 000 Btu/ft2h shall be at least 1500F(815C)
41、after the first 3 min of the test and shall be between1850F (1010C) and 2150F (1180C) at all times after thefirst 5 min of the test.9. Conditioning9.1 Establish a moisture equilibrium resulting from thedrying of the specimen(s) and test assembly in air having 50 65 % relative humidity at 73 6 5F (23
42、 6 3C) prior to testing.When impractical to achieve this condition, the tests arepermitted to be conducted when the dampest portion of thefire-resistive barrier system or test assembly has achieved anequilibrium moisture condition corresponding to drying in airhaving 50 6 5 % relative humidity at 73
43、 6 5F (23 6 3C).The specimen is permitted to be conditioned independently ofthe assembly. Various methods can be utilized to determinemoisture equilibrium, such as periodic moisture meter readingsor weight determinations of the specimen or representativepieces of similar materials.9.2 ExceptionThese
44、 moisture requirements are permittedto be waived when:9.2.1 The required moisture condition is not achievedwithin a twelve month conditioning period or,9.2.2 The construction is such that drying of the interior ofthe specimen is prevented by hermetic sealing of the construc-tion materials.10. Proced
45、ure10.1 Air TemperatureThe average temperature inside thefire-resistive barrier system at the beginning of the test shall notbe less than 50F (10C). Protect the test equipment and testassembly undergoing the fire test from any condition of windor weather that might lead to abnormal results.10.2 Fire
46、 Test:10.2.1 After the first 10 min, control the furnace pressure soas to position the neutral pressure plane as specified in 5.6.10.2.2 Continue the test at least until the desired evaluationperiod is reached, the conditions of performance are satisfied,or until failure occurs.10.2.3 Measure and re
47、port temperatures and furnace pres-sures at intervals not exceeding 1 min.11. Conditions of Acceptance11.1 Determine the fire resistance rating of a fire-resistivebarrier system for a specific electrical system component as themaximum time before which one of the following conditionsoccurs:11.1.1 Th
48、e average temperature of any set of thermocouplesfor the electrical system component is raised more than 250F(139C) above the initial temperature, or11.1.2 The temperature of any one thermocouple of the setfor each electrical system component is raised more than 325F(181C) above the initial temperat
49、ure.11.1.3 Systems reaching the criteria of 11.1.1 or 11.1.2,orwhich are terminated, at times other than even-hour timeperiods shall be rated to the 15-min increment immediatelypreceding the time at which the criteria condition or termina-tion occurred.12. Report12.1 Report the following information:12.1.1 A description and identification of the fire-resistivebarrier system, the electrical system components, and the testassembly, including drawings depicting geometry, size (length,width, and thickness), and location of test specimen(s) withinth
