1、Designation: D 5425 08An American National StandardStandard Guide forDevelopment of Fire Hazard Assessment Standards ofElectrotechnical Products1This standard is issued under the fixed designation D 5425; the number immediately following the designation indicates the year oforiginal adoption or, in
2、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. Scope*1.1 This guide provides guidance on the development of firehazard assessment standards
3、for electrotechnical products. Forthe purposes of this guide, products include materials, compo-nents, and end-use products.1.2 This guide is directed toward development of standardsthat will provide procedures for assessing fire hazards harmfulto people, animals, or property.1.3 This fire standard
4、cannot be used to provide quantitativemeasures.2. Referenced Documents2.1 ASTM Standards:2D 1711 Terminology Relating to Electrical InsulationE 176 Terminology of Fire StandardsE 603 Guide for Room Fire ExperimentsE 1546 Guide for Development of Fire-Hazard-AssessmentStandardsE 2061 Guide for Fire H
5、azardAssessment of Rail Transpor-tation VehiclesE 2067 Practice for Full-Scale Oxygen Consumption Calo-rimetry Fire Tests2.2 NFPA Codes and Standards:3NFPA555 Guide on Methods for Decreasing the Probabilityof FlashoverNFPA 901 Uniform Coding for Fire Protection2.3 International Electrotechnical Comm
6、ission (IEC) Stan-dards:4IEC 60695-1-1 Fire Hazard Testing - Part 1-1: Guidance forassessing the fire hazard of electrotechnical products -General guidelines2.4 International Organization for Standardization (ISO)Standards:5ISO 13943 Fire Safety: Vocabulary3. Terminology3.1 Use Terminology E 176, IS
7、O 13943, and IEC 60695-11, ed. 3, 199911 as the guides for terminology on fire issues(see 5.1). Where differences exist in definitions, use thosecontained in Terminology E 176.3.1.1 Terminology D 1711 should be used as the guide forterminology on issues associated with electrical or electronicinsula
8、ting materials.3.2 Use Terminology D 1711 as the guide for terminologyon issues associated with electrical and electronic insulatingmaterials.3.3 Definitions of Terms Specific to This Standard:3.3.1 electrotechnical product, nitem that generates oruses electrical power as a source of energy or that
9、is associatedwith the conduction or transmission of electrical signals orpower.3.3.1.1 DiscussionElectrotechnical products include thematerials insulating electrical wires and cables and the mate-rials enclosing other products that generate or are fed byelectricity, as well as the products themselve
10、s and all of theirparts.1This guide is under the jurisdiction of ASTM Committee D09 on Electrical andElectronic Insulating Materials and is the direct responsibility of SubcommitteeD09.21 on Fire Performance Standards.Current edition approved May 1, 2008. Published June 2008. Originallyapproved in 1
11、994. Last previous edition approved in 2002 as D 5425 02.2For 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.3Ava
12、ilable from National Fire Protection Association (NFPA), 1 BatterymarchPark, Quincy, MA 02169-7471, http:/www.nfpa.org.4Available from International Electrotechnical Commission (IEC), 3 rue deVaremb, Case postale 131, CH-1211, Geneva 20, Switzerland, http:/www.iec.ch.5Available from International Or
13、ganization for Standardization, P.O. Box 56,CH-1211, Geneva 20, Switzerland or from American National Standards Institute(ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr
14、 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.3.2 fire scenario, na detailed description of conditions,including environmental, of one or more of the stages frombefore ignition to the completion of combustion in an actualfire at specific location, or in a full-scale s
15、imulation.3.3.3 products, nmaterial, component, or end-use prod-uct.4. Significance and Use4.1 This guide is intended for use by those undertaking thedevelopment of fire hazard assessment standards for electro-technical products. Such standards are expected to be useful tomanufacturers, architects,
16、specification writers, and authoritieshaving jurisdiction.4.2 As a guide, this document provides information on anapproach to the development of a fire hazard assessmentstandard; fixed procedures are not established. Any limitationsin the availability of data, of appropriate test procedures, ofadequ
17、ate fire models, or in the advancement of scientificknowledge will place significant constraints upon the proce-dure for the assessment of fire hazard.4.3 The focus of this guide is on fire assessment standardsfor electrotechnical products. However, insofar as the conceptsin this guide are consisten
18、t with those of Guide E 1546, thegeneral concepts presented also may be applicable to pro-cesses, activities, occupancies, and buildings. Guide E 2061contains an example of how to use information on fire-test-response characteristics of electrotechnical products (electriccables) in a fire hazard ass
19、essment for a specific occupancy(rail transportation vehicle).4.4 A standard developed following this guide should notattempt to set a safety threshold or other pass/fail criteria. Sucha standard should specify all steps required to determine firehazard measures for which safety thresholds or pass/f
20、ailcriteria can be meaningfully set by authorities having jurisdic-tion.5. General Concepts5.1 It is important to understand and maintain the differ-ences between fire hazard and fire risk.5.1.1 Fire hazard is defined in Terminology E 176 as:5.1.1.1 fire hazard, nthe potential for harm associatedwit
21、h fire.5.1.2 DiscussionA fire may pose one or more types ofhazard to people, animals, or property. These hazards areassociated with the environment and with a number of fire testresponse characteristics of materials, products, or assembliesincluding, but not limited to, ease of ignition, flame sprea
22、d, rateof heat release, smoke generation and obscuration, toxicity ofcombustion products and ease of extinguishment.5.1.3 Fire hazard is defined in IEC 60695-11, ed. 3,199911 as:5.1.3.1 fire hazard, nthe possible danger of personalinjury or damage to property by fire.5.1.4 Fire risk is defined in Te
23、rminology E 176 as:5.1.4.1 fire risk, nan estimation of expected fire loss thatcombines the potential for harm in various fire scenarios thatcan occur with the probabilities of occurrence of those sce-narios.5.1.5 DiscussionRisk may be defined as the probability ofhaving a certain type of fire, wher
24、e the type of fire may bedefined in whole or in part by the degree of potential harmassociated with it or as potential for harm weighted byassociated probabilities. However it is defined, no risk scaleimplies a single value of acceptable risk. Different individualspresented with the same risk situat
25、ion may have differentopinions on its acceptability.5.1.6 Fire risk is defined in IEC 60695-11, ed. 3, 199911as:5.1.6.1 fire risk, nthe probability of fire.5.1.7 DiscussionThe risk is described in terms of prob-ability, combining the frequency of occurrence of an undesiredevent to be expected in a g
26、iven technical operation or state, andthe extent of damage to be expected on the occurrence of theevent.5.2 The primary concern in the fire hazard assessment ofelectrotechnical products is to minimize the fire hazard result-ing when such products ignite. Should a fire start, it is thendesirable to l
27、imit the fire propagation. Give consideration toexternal events, such as the outbreak of a fire in the environ-ment. In general, however, disregard deliberate misuse of anelectrotechnical product, in the fire hazard assessment.5.3 Give consideration also to heat release (both rate andamount) and opa
28、city, toxicity and corrosivity of the smokefrom a burning product and any necessary ability to functionunder fire conditions. These hazards are directly related to theignition and fire propagation. The emission of gases may also,under certain circumstances, lead to the possibility of explo-sion.5.4
29、Certain electrotechnical products such as large enclo-sures, insulated cables, and conduits, may in fact replace largeportions of surfaces and finishing materials of building con-struction or may penetrate fire-resisting walls. In these circum-stances, the requirements for fire performance of the el
30、ectro-technical products, when exposed to an external fire, mustensure that they do not contribute to the hazard of fire to agreater degree than is permitted by the building materials orstructures that are replaced.5.5 Following a detailed review of all of the expectedhazards as related to a specifi
31、c fire scenario, the final hazardassessment standards, as drafted, should include a series oftests or a single test, as appropriate, to address the specifichazard(s) defined. Single test standards are acceptable if theyaddress the major hazard(s) defined or are interrelated to thevarious components
32、involved.5.6 In order to design electrotechnical products with accept-able characteristics for minimizing fire hazard, pay carefulattention to the permissible mechanical, electrical and thermalstresses. This should minimize the fire hazard under allconditions of use: normal operation, foreseeable de
33、viationsfrom normal use and faulty operation conditions. The desiredlevel of fire hazard is achievable by the procedures in 5.6.1-5.6.3:5.6.1 The use of parts or circuit design and protection, orboth, which, under overload or failure, are not likely to igniteor to cause ignition;D54250825.6.2 The us
34、e of parts, including enclosures, which aresufficiently resistant to probable ignition sources and heatwithin an electrotechnical product; or,5.6.3 The use of designs that will adequately resist thepropagation of fire spread and surface spread by fire.6. Types of Fire Tests6.1 Technical committees e
35、ngaged in the preparation ofrequirements and test specifications with regard to fire involv-ing electrotechnical products should recognize the followingtypes of tests:6.1.1 Fire Simulation Tests:6.1.1.1 These tests examine the reaction to fire of electro-technical products, in a way as representativ
36、e as possible of theuse of the product in practice.6.1.1.2 When the actual conditions of use (including fore-seeable abnormal use, malfunction, or failure) of a product aresimulated as closely as possible, and the design of the testprocedure is related to the actual fire hazard, such tests arelikely
37、 to assess one or more relevant aspects of the fire hazardassociated with the use of the product under consideration in aspecific scenario. The results of this type of test are thus wellsuited for use as elements of a fire hazard assessment that takesinto account all the factors pertinent to an asse
38、ssment of the firehazard of the electrotechnical product in a particular end use.6.1.1.3 Do not use the results of fire simulation tests for firehazard assessment when a change of product design is made, orwhen conditions of use are changed from those simulated in thetest.6.1.1.4 Since such tests ar
39、e designed specifically for adetailed fire scenario, they often do not become test standards.6.1.2 Fire Resistance Tests:6.1.2.1 These tests are intended to assess the ability of anelectrotechnical product, or one of its parts, to preserve thevarious properties necessary for its use, under specified
40、 condi-tions of exposure to fire and for a stated period of time. In otherwords, these tests measure continuity of operation.6.1.2.2 They are intended to provide data on the electricalbehavior and performance of an electrotechnical product, orfinished assembly, under a particular condition of exposu
41、re toheat or flame.6.1.2.3 Recent studies show a need for very careful consid-eration of the test conditions and comparison with the actualfire situation and to the possible effect of any uncontrolledvariables, such as the environment in which the product isplaced.6.1.2.4 It is unlikely that the res
42、ults of fire resistance testsare directly applicable to fire hazard assessment of the corre-sponding electrotechnical product.6.1.3 Combustion Characteristic Tests:6.1.3.1 These tests examine the reaction to fire of smallstandardized specimens under controlled conditions. Thesetests are used to give
43、 data on properties related to the burningbehavior of the materials, components or end-use productstested. They are also useful for comparative evaluations. Thefire properties measured include, but are not limited to,flammability, ignitability, flame spread rate, smoke density, fireeffluent generati
44、on, and heat release rate. Examples of suchtests include the application of a number of fire-test-responsestandards to electrotechnical products.6.1.3.2 The data provided by such tests are usually notrepresentative of fire performance under conditions other thanthose to which the specimen is subject
45、ed. Combustion charac-teristic tests are most useful when designed to simulate asclosely as possible the situation to which materials, compo-nents, or end-use products may be exposed in actual use. Theymay then lead to the proper selection of materials, components,and end-use products, which will me
46、et the appropriate require-ment when testing the complete product.6.1.3.3 These tests measure responses of electrotechnicalmaterials, components, or end-use products to heat or flameunder controlled laboratory conditions. They are a step furtheraway from real fire conditions when compared to fire si
47、mula-tion tests. However, when done appropriately, results fromthese tests, in combination with those from other tests, may beuseful as elements of the fire hazard assessment of an electro-technical product in a particular end use once all the pertinentfactors are taken into account.6.1.4 “Basic Pro
48、perty” Tests:6.1.4.1 These tests are designed to measure one basicphysical or chemical property of a material. They yieldinformation that is, at least to some extent, independent of thetesting method. Some examples of such properties are: heat ofcombustion, heat of vaporization, thermal conductivity
49、, ormelting point.6.1.4.2 In a real fire situation, a number of such propertiescollectively affect the fire behavior of the electrotechnicalproduct. However, a single basic property measurement will, atmost, define only a single aspect of the fire hazard associatedwith a system. Thus, it is unlikely that the results of these basicproperty tests are useful elements of a fire hazard assessment.6.1.4.3 However, eventually, after fire safety engineeringdevelops a firmer technical base, the hope is that the results ofcombustion characteristic tests may be used to asse
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