Power line safety must be checked and double checked when working with lines overhead or underground. Observe the 10 foot Circle Of Safety at any work site.
Dan Clark describes the hazards of equipment or vehicles making contact with power lines. Learn about the Circle Of Safety, step potential and touch potential.
Dan also gives important advice on how to hop and shuffle out of an area of land which has been energized.
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Dan Clark: Be careful! A high-voltage wire could be hiding in a tree or buried just beneath a backhoe. Watch out at work sites for power lines—overhead and underground.
Hi, I’m Dan Clark with The Safety Brief. We tackle health and safety hazards in today’s demanding industrial and construction worksites a service of Creative Safety Supply.
Power line safety isn’t just for utility company lineman. Overhead and underground power lines are in the orbit of the average Joe or Jane worker. People in construction, agriculture and landscaping can sometimes tangle with live lines, so here are a few tips.
• At the minimum, use the “10 foot Circle Of Safety” rule. The safe distance depends on the voltage of the line. Up to 50 kilovolts—that’s 50,000 volts—it’s 10 feet. As voltage increases, so does distance—up to 45 feet from 1000 kilovolts.
• Don’t guess. If you don’t know the voltage, contact the power company.
• If work must be done inside that “Circle Of Safety,” contact the power company and have them pull the switch. De-energize the lines.
• Call before you dig. If you think that possibly, just maybe, there are underground lines, the local utility company can do an underground locator service.
• Know how tall your equipment is at its maximum height and how close it could get to power lines. Equipment can be a dump truck, excavator or ladder.
• Aluminum ladders and power lines don’t mix. Fiberglass only, but even wet fiberglass can be conductive.
IF CONTACT OCCURS
If part of a vehicle or construction equipment touches an overhead or underground power line, it and the ground surrounding it can become energized.
If you could see the energy in the ground you would see concentric rings, like ripples in a pond. These rings decrease in voltage farther out. This is called step potential.
If a person tries to walk away normally with two or three feet between each foot, each leg would come in contact with different voltages, leading to electricity traveling through the body. It’s important to hop or shuffle away. More on that in a moment.
If possible, have the operator move the equipment away so it’s not contacting lines.
If that’s not possible, assess the situation. If no one’s in immediate danger, everyone should stay put. Have someone call the electric company to shut off the lines.
If moving people is necessary before power is shut off, drivers or operators should jump out of the vehicle or equipment, landing on both feet. Make sure not to touch the vehicle and ground at the same time. With both feet together, hop away from the vehicle. The higher the voltage, the farther you’ll have to hop. Then shuffle away at least 30 feet. Shuffling means move your feet slowly, never more than toe to heal—no large strides.
Nearby workers should never rush in to try and help someone near electrified equipment. They’ll be victims of touch potential, providing a path for the electricity to travel to the ground.
That’s all for this episode, Power Line Safety At Work Sites. Join me again for more ways to stay safety compliant in today’s ever-changing landscape of safety requirements. I’m Dan Clark of The Safety Brief, a service of Creative Safety Supply. Save 10 percent off your entire order at creativesafetysupply.com with coupon code BIG10.
See this video on power line safety from OSHA:
Shocked man by Tom Cheney © ℗ 2015Creative Safety Supply; crane by PEO ACWA U.S. Army, public domain; power poles, explosion and concentric waves © ℗ 2015 Pixabay / OpenClipartVectors; composite © ℗ 2015 Creative Safety Supply, LLC, 7737 SW Cirrus Dr., Beaverton, Oregon 97008. All Rights Reserved; fruit picker illustration © ℗ 2015 ESFI