STP1376: Modern, Low Fire Hazard, Thin Wall Insulated Wire—A Complex Balance of Properties

    Gardner, D
    Senior Product Manager, Raychem Ltd, Dorcan, Swindon, Wiltshire

    Whiteley, RH
    Technical Fellow, Raychem Ltd, Dorcan, Swindon, Wiltshire

    Pages: 8    Published: Jan 2000


    The complexity of electrical systems required for modern mass transport systems have been increasing over recent years. The size and weight of wire and cable installations are now important issues. The technical solution to these issues has been to move from thick and medium wall insulations to thin wall insulations. In addition, increased safety levels with respect to fire hazard properties are now demanded by the industry. Ignition resistance and reaction to fire are now considered to be of critical importance, especially for underground transit systems. The production of smoke, acid/corrosive gases and toxic fire products must all be minimized.

    The functional properties of the wire, however, must not be compromised by these additional requirements of thin wall insulation and low fire hazard properties. A typical specification for such a wire therefore reflects a complex balance of properties.

    This paper describes the elements of such specifications and reviews some of the test methods used to define the properties of the wire.


    acid gas, cable, cone calorimeter, corrosivity, fire, fire hazard, flame propagation, flammability, heat release, heat release rate, insulation, low fire hazard, rail, railway, reaction to fire, rolling stock, safety, smoke, thin wall, wire

    Paper ID: STP13463S

    Committee/Subcommittee: D09.89

    DOI: 10.1520/STP13463S

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