Most of the value and type of current determine the nature of the defeat. In electrical systems up to 500 V AC mains frequency (50 Hz) is more dangerous to humans than permanent. This is due to complex biological processes in human cells. With increasing frequency, the current danger of decreasing. At a frequency of several hundred kilohertz electric shocks are not observed.

Currents depending on the value of their effects on the human body can be divided into tangible, and do not let fibrillyatsiopnye. Measurable currents - currents that cause the body as it passes through tangible irritation. Man begins to feel the effects of alternating current (50 Hz) for values ​​ranging from 0.5 to 1.5 mA and DC - from 5 to 7 mA. Within these values, there are slight trembling fingers, the heating of the skin (direct current). Such currents are called tangible threshold currents. Not dispensed currents cause muscle twitching her current value at which a person cannot take his hands from the live parts. AC is a value ranging from 10 to 15 mA. With a further increase in the current begins damage the cardiovascular system. Difficult, and then stops breathing, heart function changes. As a result of fibrillation of the heart blood does not reach the vital organs and mainly affects blood flow to the brain. The human brain is deprived of blood flow for 5-8 minutes, die, so in this case is very important to quickly and promptly provide first victim. Values ​​fibrillyatsionnyh currents ranging from 80 to 5000 mA.