Electrical Safety in Industrial Plants

Many who handle electrical equipment mistakenly believe their tolerance to electric shock is related to their ability to withstand the pain of the shock. Actually, the lethal incidence is a function of current passage through the heart region, where there are no sensory nerves to detect pain. Additionally, the onset of possibly lethal currents is only marginally higher than those ranked just painful and well within the range of industrial low-voltage power systems. While asphyxiation is the physiological result of the first zone of over-painful shock, the second zone results in heart ventricular fibrillation, or heart disfunction. Not only is the latter nonself-curing on cessation of the current, but it is generally lethal within about 3 minutes. Constant awareness and specific safety instructions to those involved with electrical or electrically driven equipment, together with vigilant policing of the safety aspects of the equipment, are hallmarks in preventing personnel shock.