OSHA lays out the facts on working safely with electricity, downed power lines
Posted March 13, 2018
OSHA recently released two fact sheets that describe the hazards of working with electricity and downed electrical lines. Working Safely with Electricity provides information to engineers, linemen electricians, and others who work directly or indirectly with electricity. Topics covered include:
- Never operate a generator indoors and ensure proper ventilation so the exhaust from generators placed outdoors does not enter a home or building.
- Be sure to turn off the main circuit breaker and lock it out before starting any generator to prevent the inadvertent energization of power lines from backfeed energy.
- Turn off generators and allow them to cool before refueling.
- Power lines;
- Know where overhead and buried power lines are located.
- Stay at least 10 feet away from overhead power lines and assume they are energized.
- De-energize and ground lines when working near them.
- Use ladders made of non-conducting materials when working near power lines.
- Extension cords;
- Only use equipment that is approved by a nationally recognized testing laboratory.
- Do not modify cords or use them incorrectly.
- Do use factory-assembled cord sets and cords that are 3-wire type.
- Use cords, connection devices, and fittings equipped with strain relief.
- When removing cords from receptacles, pull on the plugs, not the cords.
- Use double-insulated tolls and equipment that is distinctively marked.
- Visually inspect all electrical equipment before use and remove from service any equipment with frayed cords, missing ground prongs, cracked tool casings, etc.
- Electrical incidents;
- Ground all power supply systems, electrical circuits, and electrical equipment.
- Inspect electrical systems frequently to ensure a continuous path to ground.
- Use double-insulated tools and ground all exposed metal parts of equipment.
- Avoid standing in wet areas when using portable electrical tools.
Working Safely Around Downed Electrical Wires is designed for workers involved in cleanup and recovery efforts following major disasters and weather emergencies. Downed and low-handing electrical wires can present life-threatening dangers to workers, as these wires can still be energized following a storm.
OSHA says workers should always consider all electrical equipment, lines, and conductors to be energized, because circuits do not automatically turn off every time a power line falls into a tree or onto the ground. These lines can be an electrocution hazard if someone touches them or the ground nearby.
Another potential hazard created by downed lines is energized objects. Downed wires can energize fences, water pipes, bushes and trees, telephone and fiber optic cables, and other nearby objects. OSHA points out that even manhole castings and reinforcement bars in pavement can became energized by downed wires.
Backfeed from the improper connection of portable generators to a building’s electrical systems is yet another hazard electrical workers need to be aware of. Backfeed is a dangerous condition created when temporary sources of electricity are connected to the damaged permanent system which causes electricity to flow inside and outside a structure through connected lines and equipment. To avoid backfeed, OSHA reminds workers to always ensure the proper lockout/tagout procedures are followed and to avoid connecting two electrical sources to the same circuit.
The fact sheet lists the following eight “Rules to Live By”:
- Do not assume that a downed power line is safe simply because it is on the ground or it is not sparking.
- Do not assume that any wire is a harmless telephone, television, or fiber-optic cable, and does not carry lethal current.
- Treat everything electrical as energized until tested and proven to be de-energized.
- Never go near a downed or fallen electric power line.
- Electricity can spread outward through the ground in a circular shape from the point of contact. As you move away from the center, large differences in voltages can be created.
- Never drive over downed power lines. Assume that they are energized.
- If contact is made with an energized power line while you are in a vehicle, remain calm and do not get out unless the vehicle is on fire. If possible, call for help.
- If you must exit any equipment because of fire or other safety reasons, try to jump completely clear, making sure that you do not touch the equipment and the ground at the same time. Land with both feet together and shuffle away in small steps to minimize the path of electric current and avoid electrical shock. Be careful to maintain your balance.
J. J. Keller's Electrical Safety: Training for Unqualified Employees - DVD Training helps train unqualified employees on safety regulations.
J. J. Keller's FREE Workplace SafetyClicks™ email newsletter brings quick-read workplace safety and compliance news right to your email box.