Engineering Standards in Electric Shock

Abstract When an electrical current passes through human tissue, it can cause lesions to the skin, trauma to the organs, and sometimes death. The severity of the result is dependent on several electrical factors: current, voltage, resistance of the tissue, and the time that the voltage is applied. The key parameter in this discussion is electrical current . The basic principle of Ohm's Law is extremely important. It is frequently misunderstood or misrepresented in court documents. As with any electrical component, when the human body is subjected to an applied voltage , because it has a characteristic parameter known as resistance , there will be a current flow through the body, provided there are two points of electrical contact and the points have a voltage difference between them. As an example, assume that a 120 V potential exists at the first contact point on the right hand and 0 V, the ground or reference for measuring the 120 V, at the second contact point on the left hand, as shown in the Fig. 6.1. If there is a good electrical connection at the two points on the body, an estimate for the resistance can be taken as 1000 Ω. Ohm's Law yields, from the division of 120 V by 1000 Ω, 0.120 A as the current flowing through the body. In the field of electricity/electronics, the 0.120 A is expressed as 120 mA. The question then becomes: Just what are the effects of the current on the human body?