Electrical Hazards...An Overview
An electrical hazard is a situation where a worker makes direct contact with electricity from an energized source or a conductor in contact with an energized source. From that contact, the worker may sustain an electrical shock, which can cause injuries ranging from surficial burns to death. Whether dynamic or static, all electrical systems have the potential to injure workers.
Dynamic electricity is the uniform motion of electrons through a conductor. This type of electricity is also known as an electric current. Conductors materials that allow the flow of electrons to move through them. Examples of good conductors include metals, sea water and the human body. Some sources of dynamic electricity on the jobsite include:
- Live wires exposed during digging or excavation activities;
- Exposed electrical parts during electrical work activities;
- Improperly grounded power tools;
- Overhead power lines;
- Damaged wire insulation; and,
- Wet conditions around electrical equipment.
Some methods to mitigate dynamic electrical hazards include:
- Ensure power tools are properly grounded during use;
- Inspect electrical cords for fraying or other damage prior to use;
- Unless it’s designed for wet use, always use power tools in dry areas; and
- Limit the use of extension cords and avoid using multiple extension cords on the same equipment.
Static electricity results from an imbalance of negative and positive charges in an object. As charges accumulate on the surface of an object, they can be released or discharged when they find a circuit, such as a person. Some examples of dangerous static electricity on the jobsite include:
- Static electricity can create a spark, which could ignite a flammable materials, such as when fueling a vehicle;
- Dust clouds of combustible materials can build up a static charge, which could ignite the cloud; and,
- Lightning strikes.
Some methods to mitigate static electrical hazards include:
- Avoid getting in and out of your vehicle during refueling to prevent the buildup of a static charge;
- Use dust-collection methods to prevent the accumulation of combustible dust clouds; and,
- Stay indoors during a lightning storm. If not, avoid objects that conduct electricity.