Vertical Clearance

It would seem obvious that using portable metal ladders around live electrical components is dangerous. However, statistics indicate that not everyone gets it. The National Institute of Occupational Safety and Health (NIOSH) identified at least 154 electrocutions between 1992 and 2005 resulting from portable metal ladders that came in contact with overhead power lines. The vast majority of these electrocutions happened while raising, lowering or moving the ladder.

To illustrate how these accidents happened and prevent similar incidents, it’s helpful to look at two case studies of ladder-related fatalities.

The first case study involves a 32-year-old employee who was electrocuted when the metal ladder he was carrying contacted an overhead power line. His primary language was Spanish, but he spoke some English. The victim was part of a crew working at a residence. As the daily cleanup began, the victim picked up the 40-foot metal ladder he was using and lowered it to about 20 feet. As he carried the ladder to the company van, the foreman and a coworker yelled a warning in both English and Spanish about the power line, but the ladder contacted the 13,200-volt (V) line. The victim was taken to the local hospital by ambulance where he was pronounced dead at the emergency room.

The victim in the second case study was a 24-year-old laborer who was electrocuted while repositioning the metal ladder he was working on. While moving a 28-foot metal extension ladder that was extended to about 26 feet, it came in contact with a 24,000V overhead power line. The line was located 21 feet above ground at a distance of about 16 feet from the work area. The foreman heard a buzzing sound and turned to see the victim gripping the ladder before falling to the ground. He was pronounced dead at the emergency room.

Since the accidents were so similar, NIOSH’s recommendations were the same for both. OSHA regulations require or suggest many of the recommendations, both in the general industry and construction standards. These recommendations were divided into two sections, according to whom they applied: employers or employees.

The recommendations to employers dealt with how the workplace is set up and careful preplanning for ladder use.

• Eliminate the use of metal ladders near energized overhead power lines. The appropriate ANSI-approved nonconductive ladders should be used in the place of metal ladders.
• Overhead power line locations should be identified during initial work site surveys, especially when ladders will be used. The locations should be noted on site diagrams that will be used by supervisors and workers.
• When work is performed around overhead power lines, notify the local electric utility company for assistance.
• Consider ladder length, and allow room for ladder staging (raising, lowering and moving ladders).
• Never store materials or equipment near or below energized power lines.

Once on-site, put into effect many of the recommendations for planning.

• During the site safety program and orientation, use diagrams that include the position of overhead power lines to educate supervisors and workers about line placement and hazards.
• During safety training, or any training for that matter, consider the primary languages and reading levels of the workers. The training must clearly cite the risks and consequences of contacting power lines. The program can be first-rate, but if the workers don’t understand or remember it, the program is little more than an expensive waste of time. Providing hands-on practice in recognizing hazards and avoiding unsafe conditions with ladders and overhead power lines can go a long way toward increasing safety.
• Help ensure ladders can’t touch power lines by checking that they are stable, level and sufficiently supported.
• Workers need to have a way to contact emergency services in the case of a medical emergency. Training should also include how to approach injured workers and ways to provide aid during an electrical incident, including first aid, cardiopulmonary resuscitation and the use of automated external defibrillators.

During prejob meetings, safety toolbox talks or any safety training, it is essential to stress the importance of the workers noting the location of overhead power lines before they begin each job. Employees should also do the following:

• Assume all power lines are energized and dangerous.
• Never use metal ladders when working around or near power lines.
• Always lower ladders and carry them horizontally.
• Never touch or go near a person or equipment (such as a ladder) that is in contact with a power line.

Being aware of and learning from the hazards illustrated by these case studies can help to keep everyone who works with or is simply around electricity and power lines safe from harm.

KELLY is a safety and health specialist with Intec, a safety consulting, training and publishing firm that offers on-site assistance and produces manuals, training videos and software for contractors. She can be reached at 800.745.4818 and Joe O’Connor edited this article.

About the Author

Diane Kelly

Safety Columnist
Diane Kelly is a safety and health specialist with Intec, a safety consulting, training and publishing firm that offers on-site assistance and produces manuals, training videos and software for contractors. She can be reached at 800.745.4818 or dkell...

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