Electric Hazards and the Human Body

There are two known hazards of electricity — thermal and shock. A thermal hazard is one where excessive electric power causes undesired thermal effects. A classic example of this is the short circuit, insulation on wires leading to an appliance has worn through allowing the two wires to come into contact. This could start a fire in the wall of a house.

A shock hazard occurs when electric current passes through a person. Electrical currents through people produce tremendously varied effects. An electrical current can even be used for positive effects like to block back pain. The possibility of using electrical current to stimulate muscle action in paralyzed limbs, perhaps allowing paraplegics to walk, is also under study. Still, many in the general public think of electric current running through the body as both dangerous and potentially fatal. The major factors upon which the effects of electrical shock depend are the amount of current, the path taken by the current, the duration of the current, and the strength of the current.