Fire Safety Science Digital Archive

The published data on the pressures developed in vented dust explosions has been reassessed in an attempt to bring it together and form a basis for discussion. Nine basic assumptions are listed, the most important being that at some instant in a severe explosion the combustion could be taking place throughout the whole volume of the vessel. The assumptions have led to the derivation of equations relating the explosion pressure to the area of vent, the volume of vessel, and explosion parameters of the dusts. Calculated explosion pressures have been compared with the published data. Only unrestricted vents have been considered. The severe conditions of explosion would be of most interest in practice, to the design engineer, but modified calculations could be made for less severe conditions. The present ad hoc procedure for stipulating vent area has been compared with calculation, and appeared to be reasonable. The gaps in the published data were listed, and attention drawn to those aspects where further information is particularly required.