Blast waves in free air

The equations presented for the calculation of blast wave peak overpressure and positive phase impulse approximate values, for the case of military explosives detonated in a free atmosphere, may be found useful for the simple design of protective systems and the estimation of the amount of explosive required to achieve a desired effect. A section is devoted to the derivation of simple equations characterizing blast wave damage as a function of charge weight and distance. The three main causes of damage effect are peak overpressure, pressure impulse, and the product of the peak overpressure multiplied by intermediate range impulse.