Blast injuries extremity

An electric arc flash is the result of an arc fault that superheats the air around it, expanding and creating a pressure wave within an electrical enclosure. This massive heat and energy wave can inflict serious injuries. Extreme temperatures reach up to 35,000 degrees Fahrenheit — almost four times the surface temperature of the sun. And the pressure wave from the blast can equal that of a hand grenade. 

Figure 53.3 summarizes injury mechanisms associated with torso impact deformation. For low speeds of deformation, the limiting factor is crush injury from compression of the body (C). This occurs at C = 35-40% depending on the contact area and orientation of loading. For deformation speeds above 3 m/sec, injury is related to a peak viscous response of VC = 1.0 m/sec. In a particular situation, injury can occur by a compression or viscous responses, or both, as these responses occur at different times in an impact. At extreme rates of loading, such as in a blast-wave exposure, injury occurs with less than 10 15% compression by high-energy transfer to viscous elements of the body. 

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