Electrical Hazards
4. Effects of Electric Current
In summary, the effects of electric current may be divided into:
Direct effects
a) Functional alterations
Cardiac arrest: produced when a current passes through the heart and its effect on the organism translates as circulatory arrest due to cardiac arrest.
Asphyxia: produced when an electric current passes through the thorax. It impedes the action of the muscles of the lungs and breathing.
Burns: Internal or external burns due to a current passing through the body or due to the proximity of an electric arc.
Tetanization or muscular contraction: This consists in the annulment of the capacity of the muscles to react, thus impeding voluntary separation from the point of Contact.
As we have already seen, this phenomenon serves to define the concept of the limit current.
Ventricular fibrillation:This is produced when a current passes through the heart and its effect on the organism translates as circulatory arrest due to alteration of the cardiac rhythm.
It occurs at current intensities of around 10 mA.
Fibrillation is produced when the electric shock lasts for more than 0.15 seconds, i.e. 20% of the total duration of the average cardiac cycle in humans, which is 0.75 seconds.
Permanent injuries: Produced by destruction of the affected part of the nervous system (paralysis, permanent contractures, etc).
b) Secondary alterations
Burns.
Renal, ocular, auditory complications, etc.
Indirect effects
These are not caused by the current itself, but are due to involuntary acts on the part of affected individuals, such as knocks against objects, falls, etc., brought about after Contact with the current, which, although in itself causes no more than a shock or unpleasant sensation, may however cause the person to lose their balance followed by a fall onto the same or a different level and the hazard of injury, fractures or being hit by moving or immobile objects that may even result in death.
