The Effect Of Scale On Smoke Emission

Abstract

Parallel instrumentation for measuring fire smoke aerosols have been developed in bench scale as part of the Cone Calorimeter, and in large scale in a specially built measuring rig. Since the principles of design were similar, data could be directly compared. For solid and liquid combustibles, it was found that large-scale smoke emission rates could be well represented from Cone Calorimeter data if the specimen mass loss rates per unit area, were matched for the two cases. The matching of the mass loss rates was accomplished in bench scale by exposing the specimen to a suitable level of external irradiance. The results are presented in terms of the specific extinction area, which is defined as the smoke extinction cross-section, per unit mass. The specific extinction area, when computed on a smoke particulate mass basis, was seen to be independent of fuel type and of the conditions of test.