Aerial Equipment & Electrical Hazards
Job Steps - Using aerial lifts to do tree work near utility lines.
- Non-insulated aerial lifts
- Electrically charged chippers
- Dirty insulated aerial lifts
Always know where the utility lines are in relation to you and your equipment. Never work with your back to electrical wires or move a bucket into position without looking where you are going. Maintain a safe working distance from electrical wires. Aerial booms can conduct electricity, creating a hazard for the operator as well as the people on the ground.
How Could This Accident Have Been Prevented?
An experienced qualified line clearance tree trimmer was removing a large poplar tree that was about 5 feet from a 35,000-volt line. He was working out of a 55-foot bucket truck that was fully insulated and had recently passed all of the necessary safety and maintenance inspections.
The bucket operator removed most of the tree and was working on the 45-foot high butt section. He was chunking down 10-foot sections when the top he was cutting settled down onto the saw, jamming it. Being unable to remove the saw and getting very frustrated - he maneuvered the bucket up higher to get better leverage while continuing to grasp the saw. His forehead (he was not wearing a hard hat) came into contact with the 35,000-volt line, killing him instantly.
Why was he killed even though he was in an insulated bucket?
This qualified line clearance tree trimmer was killed because he forgot where he was. He also forgot the first rule of electricity - electricity is always looking for a path to the ground - and while the electricity will not flow through an insulated piece of equipment such as an aerial lift, it will travel through a tree and you.
If any part of your body touches a grounded object such as a tree or a wet rope and you also come into contact - directly or indirectly - with an energized wire, you become a path to the ground.