The Kentucky Fatality Assessment and Control Evaluation (FACE) Program is tasked with investigating fatalities and making recommendations to ensure they do not occur again. This is one of their recent cases.
On Monday, Sept. 10, 2018, at 8:00 a.m., a 16-year-old male roofer arrived at the worksite to begin roofing work on a private residential home. The homeowners, a husband and wife, contacted a local general contractor to replace the roof on their home. The owner of the general contracting company hired a subcontractor to perform the work, a process he informed authorities that he performs regularly. The crew began work on the back of the house and quickly worked together to complete the task.
At approximately 12:00 p.m., the 16-year-old victim gathered a model D1828-2EQ Werner aluminum extension ladder and moved to the front of the house to begin work there while the other three men moved on to the side of the house. At the front of the house, there were two 4 ft. x 4 ft. boxwood bushes planted 3 feet from the home’s exterior wall at the point where the victim was attempting to access the roof.
There were no witnesses, but it is believed that because of the bushes, the victim was having trouble accessing the roof. With the ladder still fully extended, the victim attempted to move it closer by lifting the ladder and walking between the bushes to find a suitable base. The ladder became unstable, causing the victim to lose his balance falling backwards.
As the victim and ladder were falling, the ladder fell into a top phase power line carrying 7.2 kilovolts (7,200 volts). Because the victim was still in contact with the highly conductive aluminum ladder when it struck the power line, electricity was able to travel through the metal and into the young worker. He was immediately electrocuted.
After hearing a noise from the front of the home, the owner of the subcontracting company went to investigate and found the victim lying unresponsive on the ground. He immediately knocked on the home’s front door and frantically tried to communicate to the wife what had happened and asked for help. The homeowner called 911 at 12:15 p.m. When EMS arrived eight minutes later, they observed the victim lying on the ground facing upwards. Both of the worker’s boots had burn holes near the fifth toe; burn marks were also present on the stomach area. He was pronounced dead by the county coroner minutes later.
In an interview with the county sheriff’s office with the help of a translator, the coworkers stated that they were on the side of the home and did not observe this incident. The owner of the subcontracting company acknowledged that he had instructed the victim to move to the front of the house to continue work there. Both coworkers were aware that the victim was putting up a ladder to access the front roof and that the victim had not asked for assistance.
Cause of Death
The cause of death was high voltage electrocution.
Contributing Factors
Occupational injuries and fatalities are often the result of one or more contributing factors or key events in a larger sequence of events that ultimately result in the injury or fatality. National Institute Occupational Safety and Health (NIOSH) investigators identified the following unrecognized hazards as key contributing factors in this incident:
- Work performed outside youth employment regulations
- Lack of hazard recognition and safety training
- Use of a conductive ladder around high voltage lines
- Transporting an extension ladder in the vertical position
Recommendations
Employers should perform a job hazard analysis prior to performing a new task.
In this incident, the employees were exposed to working at heights, working from ladders, and close proximity to high voltage power lines. A job hazard analysis would recognize the numerous hazards that the roofing workforce was being exposed to so that necessary safety precautions could be undertaken.
Employers should become familiar with and comply with all federal, state, and local regulations associated with youth employment, including safety training and hazard recognition.
Due to the high injury rate of minors in the workplace, the Commonwealth of Kentucky has very specific child labor laws, providing guidelines on how many hours per week young workers are permitted to work, what times of the day they are allowed to work, and what occupations are prohibited for minors under the age of 185. The Kentucky Labor Cabinet lists 19 occupations that are prohibited for minors, including #16: “Roofing operations and all work on or about a roof.” Subcontractors and contractors should familiarize themselves with Kentucky child labor laws and Federal child labor laws before employing youths in specific occupations. In addition federal laws apply Hazardous Occupations from the US department of labor: Eighteen is the minimum age for employment in non-agricultural occupations declared hazardous by the Secretary of Labor. The rules prohibiting working in hazardous occupations (HO) apply either on an industry basis, or on an occupational basis no matter what industry the job is in. Parents employing their own children are subject to these same rules. General exemptions apply to all of these occupations, while limited apprentice/student-learner exemptions apply to those occupations marked with an *.
These rules prohibit work in, or with the following:
HO 16.
Roofing operations and all work on or about a roof.
Employers should consider using non-conductive ladders when working near electrical lines.
At the time of the incident, the victim was using an aluminum ladder to access the roof. Because of its extremely low resistivity and extremely high conductivity, aluminum is one of the best electrical conducting metals, behind only silver, copper, annealed copper, and gold. As the ladder contacted the overhead power line, 7,200 volts and 16 amperes (amps) travelled through ladder, into the victim, and exited his body via the stomach and each foot’s fifth (pinky) toe. At values as low as 100 milliamps (.1 amps), death can occur. Due to the high amount of amperes that entered the victim’s body, cardiac arrest occurred instantly.
In order to prevent similar incidents, the employer should consider using a non-conductive ladder, such as those made of a fiberglass-reinforced polymer, when working around live power lines. Due to its low electrical conductivity and high resistance to corrosion, these ladders would make a safe and practical choice when working outdoors around electricity. However, employers should ensure that these fiberglass ladders are maintained properly as required by 29 CFR 1926.1053. Unmaintained ladders may accumulate excess dirt or moisture that can conduct electricity in the event it encounters a high voltage line.
Employees should always lower the extended section and transport ladders horizontally.
The victim was moving a model D1828-2EQ Werner aluminum extension ladder that weighed approximately 56 lbs. When collapsed, the ladder was 14 feet tall and had a maximum open extended length of 25 feet. At the time of the incident, the victim, who measured 5’10” tall and weighed 165 lbs., was moving the ladder, which was extended to the maximum length of 25 ft. As the ladder became unstable and began to fall, the victim may have been unable to support the ladder’s top-heavy design while standing on uneven terrain, which allowed it to contact the power line.
In instances where an extension ladder needs to be relocated, employees should lower the extended portion of the ladder until it is appropriately collapsed, carefully lay the ladder down, and transport it horizontally while grasping the ladder’s middle section with both hands in order to safety manage its weight. Once the ladder is placed in the necessary area, ensure the base is secure and re-extend the ladder to the appropriate height. Had the ladder been lowered and transported horizontally, the high voltage line could have been avoided.
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This case report was developed to draw the attention of employers and employees to a serious safety hazard and is based on preliminary data only. This publication does not represent final determinations regarding the nature of the incident, cause of the injury, or fault of employer, employee, or any party involved.