Accidents involving electricity are common. All electricians should review the basic electrical hazard accident--prevention measures. It’s important to ensure the following five protective methods are in place.
Provide ground-fault protection
There are two options for a job site: using ground-fault circuit interrupters (GFCIs) or an assured equipment-grounding conductor program (AEGCP).
A GFCI will detect an imbalance between the energized conductor and the return neutral conductor. An imbalance occurs, for instance, when the current leaks from a tool through the body of a person who is grounded. At this point, the GFCI would trip and immediately stop the flow. GFCIs are available as portable devices or can be installed in a circuit.
An AEGCP is a written company procedure that requires periodic testing of all equipment-grounding conductors of cord sets and of those connected to receptacles to ensure no faults will occur. The company must keep records of the tests. Moreover, one or more designated people must continuously enforce the AEGCP at the site.
Ensure proper insulation
A simple (yet often overlooked) method that provides protection from electrical accidents is to check the insulation of conductors each day. Any cable with exposed wires or scuffed or cut insulation should be removed from service. Depending on the task at hand, employees may need to use insulated shoes, gloves and hand tools.
Observe guarding requirements
Regulations protect employees by limiting access to energized conductors and equipment by location, such as when working under overhead lines, or by the installation of covers or other permanent barriers. Whenever it’s necessary to work in these areas, on scaffolding or on lifts, employees should know the minimum approach distances and necessary personal protective equipment.
Grounding may be the most fundamental element of electrical protection. That third neutral conductor in cables we often ignore is critical to ensuring employees are protected from electric shock, the likelihood of fire is minimized and electrical equipment is protected from damage. Employees must check all cables and equipment to ensure the ground is in place. Qualified electricians must also ensure grounds are properly applied when de-energizing to perform repairs.
Prevent current overload
Devices, such as fuses or circuit breakers, are available to protect circuits that function by limiting or cutting off the flow of electricity when a short circuit or overload occurs. They can also prevent accidents by protecting conductors and equipment from overheating. Ensure the proper device has been installed or has not been circumvented. For example, homeowners often use an extension cord that is not made for the current it needs to carry. If the load does not exceed the breaker, disaster may result. To ensure safety, verify that wiring and breakers are compatible with the work to be performed.
Even when these safe practices are carefully followed, accidents happen, resulting in serious injuries or death. Electrical shock injuries occur when some part of an employee’s body becomes part of a circuit. The current enters the body at one point and exits at another. Other common hazards from electricity include burns, arc blasts, explosions and fires.
Shocks can occur when the following conditions are met:
• Both wires of an electric circuit are touched.
• The employee touches one wire of the circuit and contacts the ground.
• An employee is in contact with a metallic part that is “hot” when touching an energized wire and the ground.
Shocks can range in severity from a tingle to loss of muscular control to severe burns, cardiac arrest and death. The seriousness of the injury depends on how much electricity passes through the body, the path the electricity takes and how long the body is part of the circuit. The electric current passes through the body’s internal structures, so much of the damage isn’t visible; however, destruction of tissues, muscles, nerves and other internal organs occurs along the current’s path. Secondary injuries, such as falls, cuts, broken bones and burns, are likely to occur from the initial shock.
The most common types of burns are electrical, arc and thermal contact. Electrical burns are the result of current moving through the body, generating heat and damaging the involved tissues. These burns typically require immediate medical attention. Arc or flash burns occur when an electric arc or explosion results in very high temperatures near the body. Thermal contact burns occur when skin comes in contact with hot surfaces of overheated electrical components.
Another danger results when high-energy arcs cause fires or explosions, sending metal fragments flying in all directions.
Electricity is necessary at every job site, so the potential dangers and injuries must be acknowledged and care taken to minimize their occurrence. Even a minor electrical mishap can result in a fatality.
KELLY is a safety and health specialist with Intec, a safety consulting, training and publishing firm that offers on-site assistance and produces manuals, training videos and software for contractors. She can be reached at 800.745.4818 and firstname.lastname@example.org. Joe O’Connor edited this article.