Fire Safety Science Digital Archive

The smouldering of cocoa and grass dusts under airflow conditions has been compared with that of beech and deal sawdusts described earlier. The dusts were formed into small trains and placed in a wind tunnel, and measurements were made of the effects of airflow and train size upon the rate of smouldering and of the effect of airflow on the minimum depth of dust layer necessary for sustained smouldering. Certain aspects of the behavior of cocoa and grass dusts smouldering under airflow conditions are similar to the behaviour of beech and deal sawdusts. In the presence of slight draughts, trains of grass dust only 3 mm deep can initiate smouldering in covering layers of wood shavings and newspaper, with the subsequent production of flame, thus showing that grass dust is particularly hazardous.