Electricity is one of the most common causes of fire in homes and workplaces. Explosions have also resulted from electrical sources. OSHA’s electrical standard is designed to protect employees exposed to dangers such as electric shock, electrocution, fires, and explosions. OSHA’s General Industry electrical standards contained in 29 CFR 1910 Subpart S.
On average, a worker is electrocuted on the job every day. There are four main types of electrical injuries; electrocution, electrical shock, burns, and falls. Electrical shock is produced when a current passes through the body. Severity of the shock depends on the path of the current and the amount of current flowing through the body, and the length of time the body is in the circuit.
The difference between electrocution and electric shock is that electrocution ends with death. Electrocution causes death or severe injury when a high voltage electric current passes through the body. An electrical shock is when an electric current travels through the body, causing muscles to involuntarily seize. An electrical shock can occur even if there is no direct contact with the source of electricity, as it can travel through the air and come in contact with hair and skin. The human body has a low resistance to electricity causing it to act as a good conductor. The severity of damage from electric shock can range from skin burns, twitching of muscles, heart attack, to death, depending on the voltage of current that is present during the shock. A current can travel through the skin’s surface, then through the muscles, and into the body’s organs. Other injuries can include seizures, breathing problems, and broken bones.
Electrical accidents happen with a combination of unsafe equipment and/or installation, workplaces made unsafe by the environment, and unsafe work practices. Remember, low voltage does not mean low hazard. To avoid hazards:
- Look for overhead power lines and buried power line indicators. Post warning signs.
- Contact utilities for buried power line locations.
- Stay at least ten feet away from overhead power lines.
- Unless you know otherwise, assume that overhead lines are energized (live).
- De-energize and ground lines when working near them. Other protective measures include guarding or insulating the lines.
- Use non-conductive wood or fiberglass ladders when working near power lines.
- Use extra caution when working with electricity when water is present in the environment or on the skin. Pure water is a poor conductor, but small amounts of impurities, such as salt and acid (both found in perspiration), make it a ready conductor.
Definitions of common electrical verbiage:
- Current = the movement of electrical charge
- Resistance = opposition to current flow
- Voltage = a measure of electrical force
- Conductors = substances, such as metals, which have little resistance to electricity
- Insulators = substances, such as wood, rubber, and glass, which have high resistance to electricity
- Grounding = a conductive connection to the earth which acts as a protective measure