Introduction :- Explosions are characterised by a shock-wave which can be heard as a bang and which can cause damage to buildings, breaking windows and ejecting missiles over distances of several hundred metres. The injuries and damage are in the first place caused by the shock-wave of the explosion itself. People are blown over or knocked down and buried under collapsed buildings or injured by flying glass. Although the effects of over-pressure can directly result in deaths, this would be likely to involve only those working in the direct vicinity of the explosion.The history of industrial explosions shows that the indirect effects of collapsing buildings, flying glass and debris cause far more loss of life and severe injuries. The effects of the shock-wave vary depending on the characteristics of the material, the quantity involved and the degree of confinement of the vapour cloud. The peak pressure in an explosion therefore vary between a slight over-pre...