A technique for the quantification of material properties for fire hazard assessment of cables

A new technique has been developed for quantifying the fire propagation behaviour of cables under simulated large scale flame radiation conditions using the Factory Mutual Research Corporation's flammability apparatus. The cable fire propagation behaviour is quantified in terms of a fire propagation index (FPI), which is the ratio of the radiative component of the chemical heat release rate and the thermal response parameter. On the basis of the FPI values cables have been classified into three groups: group 1, for which fire propagation is not self-sustained (FPI < 10); group 2, for which fire is self-sustained, but the fire propagation rate is not rapid (20 < FPI ≥ 10); and group 3, for which fire is self-sustained and the fire propagation rate is very rapid (FPI ≥ 20). Application of cable group classifications and protection requirements are discussed. (author). 7 refs, 8 figs, 1 tab