Thermal radiation hazards from releases of LPG from pressurised storage

When a flammable liquid with a vapour pressure greater than atmospheric is released from pressurised storage, flash evaporation occurs. The ignition of such a release is likely to create a fireball which creates a short lived, but intense, source of thermal radiation.The influences of the flash evaporation process on the mechanism of flammable cloud formation and the subsequent burning of the cloud are discussed. Published information is reviewed to provide insight into those features of fireball behaviour that are influenced by the initial degree of flash evaporation and those that are not. Correlations are presented that represent consensus views on the influence of mass of flammable substance in the release on fireball diameter, duration, and radiation output.