Fire hazard assessment of polypropylene wall linings subjected to small ignition sources

ABSTRACT: The fire hazards associated with polypropylene wall linings sub-jected to small ignition sources, were evaluated using large scale experiments and cone calorimetry. A series of seven ignition sources with increasing sever-ity as recommended in BS 5852 were used in the tests. The results obtained in-dicate that ignition of the polypropylene linings is likely when exposed to igni-tion sources 5 to 7 as defined in BS 5852. It was observed that the melting behaviour of the polypropylene wall linings significantly affected the burning behaviour. A pool fire, consisting of melted polymer, formed at the base of the wall which then controlled the fire growth processes. The rate of flame spread on the lining surface which depended on the growth of the pool fire was slow because the thin polymer sheet could only supply a limited amount of melted polymer to the pool. The estimated heat release rates from the pool fire were close to the values measured in the cone calorimeter at the heat flux level of 25 kW m-2. KEY WORDS: polypropylene, cone calorimeter, heat release rate, pool fire, flame spread, ignition, small ignition source. *Author to whom correspondence should be addressed