ABSTRACT
An explosion is a sudden, violent release of energy. It is usually accompanied by a loud noise and an expanding pressure wave of gas. The pressure of the gas decreases with distance from the origin or "epicenter". Explosions caused by the sudden release of chemical energy are classified into two main types: deflagrating explosions and detonating explosions. Deflagrating explosions cause damage generally by pushing things about because of pressure differentials. Detonating explosions have higher fissile ability than deflagrations. It is this quality that makes them useful for blasting work. In addition to deflagrations and detonations there is a third category of explosion, which involves the sudden expansion of high-pressure gases, as might occur from a ruptured high pressure vessel or pipe. This category also includes the sudden expansion of pressurized liquids into gas, such as would occur when pressurized boiler feed water flashes into steam when the pressure is suddenly lowered.
