Proper maintenance and inspection of equipment is a critical part of any electrical contracting company's operations. However, keeping records of maintenance performed can be just as important — especially in the event of a serious accident, such as one that claimed the life of one Ohio electrical contractor.
The victim, a 45-year-old male who was part-owner of his firm, fell to his death after the articulating boom of the aerial lift truck he was working from collapsed. Working at a height of approximately 35 feet, the man was changing lamps on overhead streetlights along a state highway. After replacing a bulb, he began lowering the boom when the upper boom actuating chain (connecting the upper and lower boom) broke. The upper structure collapsed, hitting the truck bed and ejecting the man from the bucket. The victim struck the back of his head and neck on the truck before coming to rest on the road surface. Although he wore a 6-foot lanyard, it did not prevent him from colliding with the truck, because the distance from the lanyard's anchorage point to the truck bed was less than 6 feet. A coworker on the ground who witnessed the accident found the man unresponsive and immediately began resuscitation efforts, while a passing motorist called emergency medical service personnel. The victim was rushed to a local hospital, where he was pronounced dead. The cause of death was massive head trauma.
According to a crew member, the victim had spoken about the boom making a funny noise earlier in the day. Post-incident inspection of the articulating boom revealed that the boom actuating chain had separated, resulting in the catastrophic collapse of the upper boom. To avoid similar tragedies, NIOSH recommends the following:
Employers should direct employees to immediately cease use of an aerial lift when it emits any unusual sounds, exhibits unusual motions, or fails to properly respond to controls. This guidance should be written into company policy and included in worker training.
Employers should strictly adhere to the manufacturers' recommendations for maintenance and lubrication of aerial lift operating mechanisms. The manufacturer's operation and maintenance manual recommended that the roller chains, which included the upper boom actuating chain, be lubricated at 30-day intervals using recommended penetrating oils. Although investigators were not able to examine the aerial lift or broken chain, close examination of photos of the broken chain and roller pins revealed a dull reddish brown discoloration near the fracture area, indicating corrosion and a lack of lubrication
Employers should ensure that qualified repair personnel conduct regular maintenance and inspections of aerial lifts. The aerial lift involved in this incident was 18 years old. Company records documented periodic maintenance on the truck's engine and chassis, but no records were available to support an ongoing maintenance program and inspection on the boom structure or other assemblies of the aerial lift.
Employers should maintain accurate records for boom inspection, maintenance, and repair on aerial lifts. Proper record keeping enables employees to keep track of all repairs and adherence to the manufacturer's recommended maintenance and inspection timelines, which should help ensure safe operating conditions of the aerial lift.
Aerial lift operators should ensure that work crews using aerial lifts include at least one ground person with the ability to contact emergency assistance, if needed. This guidance should be written into company policy and included in worker training.
Reprinted with permission from the National Institute for Occupational Safety and Health (NIOSH), Division of Safety Research (DSR). All electrical-related FACE reports can be viewed in their entirety at www.cdc.gov/niosh/face/default.html.