Combustibility of Electrical Wire and Cable for Rail Rapid Transit Systems: Volume I: Flammability

Volpe National Transportation Systems Center, Technical Reference Centerhttps://doi.org/10.21949/15267581983PDFTech ReportTewarson, A.Khan, M. M.Steciak, J.Factory Mutual Research CorporationJohn A. Volpe National Transportation Systems Center (U.S.)United States. Department of Transportation. Research and Special Programs Administration. Transportation Systems CenterUnited States. Department of Transportation. Urban Mass Transportation Administration. Office of Technical AssistanceUnited States. Department of Transportation. Urban Mass Transportation AdministrationUnited StatesFiresFlammabilityInsulating materialsElectric insulating materialsRapid transitTestingSafetyCablesCombustionToxicityWiringCombustibilityDOT-TSC-UMTA-83-4.1;UMTA-MA-06-0025-83-6DTRS-57-80-C-00073Mr. Milton HolzmanThe objective of this study was to examine the flammability of wires and cables used in rapid rail transit systems. The overall goal of the study was to quantify the fire properties of wires and cables in a manner so that the relative fire hazards could be assessed under various fire scenarios expected in rapid rail systems. In this study, the following items were investigated: 1) a literature review of wire and cable fires; 2) selection of test method for combustibility evaluations of wires and cables; 3) testing of wires and cables; and 4) evaluation of ranking of wires and cables. Basically, this report is organized in three parts: an overall summary of the report; experimental details, results and discussion; and appendices providing detailed calculations for determining the different parameters used in the report. The combustibility of 31 wire and cable samples submitted by 12 manufacturers was evaluated using the Factory Mutual Small-Scale Combustibility Apparatus under simulated external radiation for large-scale fire conditions. Samples of wire and cable were ranked according to 7 parameters: ignition/surface flame spread; electrical failure; corrosivity of the fire products; generation of fuel vapors; generation of heat; generation of gaseous compounds; and light obscuration. The report states that the hazards expected in wire and cable fires depend not only on the generic nature of the insulation/jacket materials, but also on the additives, size, and construction of the wire and cable. An increase in the size of the wire and cable sample is expected to reduce the fire hazard with the degree of hazard reduction dependent on the generic nature of the insulation/jacket materials.138