Electric Shock is a condition that occurs when there is a flow of electricity through the body. It is usually caused by contact with poorly insulated wires or ungrounded electrical equipment, by using electrical equipment while in contact with water, or by being struck by lightning. The severity and effects of electric shock depend mostly on the amount of current passing through the body and the duration of contact.
A slight, harmless shock produces only a jarring or startling sensation. Severe shocks produce muscle contractions, which lead to muscular spasms, paralysis, unconsciousness, or death. A fatal electric shock is called electrocution. Burns may occur where the current enters and leaves the body.
The chart below shows the general relationship between the degree of injury and amount of current for a 60-cycle hand-to-foot path of one second's duration of shock. While reading this chart, keep in mind that most electrical circuits can provide, under normal conditions, up to 20,000 milliamperes of current flow.
1 Milliampere Perception level
5 Milliamperes Slight shock felt; not painful but disturbing
6-30 Milliamperes Painful shock; "let-go" range
50-150 Milliamperes Extreme pain, respiratory arrest, severe muscular contraction
1000-4,300 Milliamperes Ventricular fibrillation
10,000+ Milliamperes Cardiac arrest, severe burns and probable death
When an electric shock is caused by contact with electrical wires or equipment, the victim should be freed from the source of current immediately—either by shutting off the source (as by pulling a circuit breaker) or by separating the victim from the point of contact. Since the human body is a good conductor of electricity, the victim should not be touched with bare hands; dry, insulated gloves or a dry, nonconductive material (such as rubber or wood) should be used to push or pull the victim away from the source of current. In addition, the rescuer should stand on something dry and nonconductive.
A survivor of electric shock is often panicky with fear and is pale, trembling, and sweating. A doctor should be called immediately. First aid includes keeping the victim warm and in a horizontal position. If the victim stops breathing, mouth-to-mouth resuscitation should be given. Professional medical treatment may include treatment for burns and the administration of drugs and oxygen.
In most cases electric shock can be prevented by taking certain precautions, especially around the home.
There are various ways of protecting people from the hazards caused by electricity, including insulation, guarding, grounding, and electrical protective devices. Workers can significantly reduce electrical hazards by following some basic precautions:
- Inspect wiring of equipment before each use. Replace damaged or frayed electrical cords immediately.
- Use safe work practices every time electrical equipment is used.
- Know the location and how to operate shut-off switches and/or circuit breaker panels. Use these devices to shut off equipment in the event of a fire or electrocution.
- Limit the use of extension cords. Use only for temporary operations. In all other cases, request installation of a new electrical outlet.
- Use only multi-plug adapters equipped with circuit breakers or fuses.
- Minimize the potential for water or chemical spills on or near electrical equipment.
- Only trained and certified electricians must attempt repairs on electrical equipment.
- Do not tamper with electrical equipment.
- Obey all warning signs especially around high voltage electrical equipment