Fireball 4 : Burning of a flammable gas or vapour cloud. The buoyancy of the hot combustion products may lift the cloud from the ground, forming a mushroom shape. Hazard is primarily due to thermal effects
Cabinet Office, Lexicon of UK Civil Protection: A developing single point of reference for UK Civil Protection Terminology - Version 2.0.1, Emergency Responder Interoperability Lexicon, London, UK 2011. http://www.cabinetoffice.gov.uk/cplexicon, (Emr Mgt - Brit) {545}