The accidental electrocution Friday of a Virginia Department of Transportation electrician's helper points out the danger of working with electrical wires, even for professionals.

Darnell Allen Johnson, 25, of 677 50th Place SE in the District, was killed as he and a coworker were trying to restore electricity to a light pole along the southbound lane of I-395 in Arlington. Johnson had climbed into a small concrete box containing electrical wires that was located off the road when he collapsed.

"What happens in an electrocution is that someone becomes the shortest path to the ground," said William Dupler, Arlington's construction engineering supervisor for field inspections.

Dupler said that county inspection officials urge people to stay away from electrical wires.

"The point is, people shouldn't work on hot wires," he said. "It takes special training and it means taking special precautions."

Dupler said that the most important precaution to take when performing electrical work in a home is to turn off the main power supply to the house. But he cautioned that even turning off the main supply does not guarantee there will not be an electrical mishap.

Virginia Power officials also urge people to avoid working with electrical wires. "The bottom line is stay away from power lines," said Jim McDonald, a spokesman for the company.

"You have to treat all wires as if they're energized," said Maynard Guill, a division manager for Virginia Power, who has been with the company for nearly 30 years.

"There's an electrical potential between an electrical conductor and the ground, and any time there's a connection between those two, current flows," Guill said.

Virginia Power's tips to homeowners include:Never trim or remove trees near power lines. Use extreme caution when using metal ladders while cleaning gutters or housepainting. Do not climb utility poles. Call for assistance if an animal climbs a utility pole or a tree falls across a power line. Call a professional electrician to install appliances or light fixtures. Be sure to turn off the main power source before attempting any work yourself.

Virginia occupational safety and health officials, who are investigating Friday's accident, have handled 52 cases involving workplace deaths so far this year, 10 of which have been caused by electric shock.