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The action of electric current

The electric shock may occur from the so-called voltage step. Defeat in this case happens when a man's feet touch two points of land with different electrical potentials. Step voltage occurs when you fall to the ground high-voltage wires, with grounding defective electrooborudovania, when discharge of lightning to the ground, etc. When getting under step voltage current passes from one foot to the other on the bottom of the loop". This path of current flow through the human body is less dangerous. In the same way, when a person because twitching muscles of the lower limb falls, lower loop becomes full, more dangerous. It is considered dangerous to log on to a distance 10 steps in the area of the fallen wire high-voltage network. However, the wider step, the greater the potential difference and those under more stress and gets people.
Lethal injury can occur from current small voltage, and Vice versa, a man can survive under the current very high voltage. The degree of defeat technical electricity to influence the path of current flow in the body. In the literature they are called conditionally loops current. The most dangerous is the path when an electric current passes through the brain or the heart that can occur when the electrical circuit left arm and left leg, right arm and left foot, left and right hands, chest or back and hands, head and legs or the arms and other electric current passes mainly through the tissues with the highest electrical conductivity and the least resistance.
The resistance of tissues electric current increases in the following sequence - the blood, the mucous membranes, liver, kidneys, muscles, the substance of the brain, lungs, tendons, cartilage, nerve, bone, skin. The greatest resistance has dry skin. Moist skin and excessive sweating contribute to the electric shock.
The condition of the body at the moment of impact of current importance. Persons suffering from diseases of the cardiovascular system, kidneys, endocrine glands and anemia, the elderly, children, pregnant women, as well as actors who are in a condition of alcoholic intoxication, especially exposed to electric current. Deep asphyxia, overheating reduce the body's resistance to electric current.
Electric energy has an impact not only at the site of contact, but also on the whole organism that may show different symptoms depending on the defeat of one or other organ systems. The mechanism of the overall impact of electricity is considered as a shock, leading to impairment of respiration and circulation.
The shock evolving as a result of the action of electric current, belongs to a group of pain. With a longer passage current shock occurs due to a sharp pain irritation of receptors, nerve trunks, painful muscle cramps and spasm of blood vessels (coronary heart pain).
When the spread in the body of the electric current significant intensity death occurs, as a rule, immediately resulting from primary cessation of breathing or heart problems. Sometimes there is the so-called slow death when the victim some time after the shock marked convulsions, he screams and tries to free himself from the current conductor. Often the victim is exempted from Explorer, but soon dies. The death of the victim may not come until after a considerable period of time after exposure to current. During the circuit of the electric current is the maximum expiratory, for power expiratory muscles more than vaihtelee. This greatly aggravates the course of electric shock, because the body is much reduced oxygen reserve.
Changes in the place of contact with the conductor during the current associated with the transition of the electricity into other forms of energy, which accounts for its warm, mechanical and physicochemical effects.