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Too often, when it comes to electrical safety on the job site, it is assumed that the protection is only about electricians or those working around live wires. Unfortunately, this is a gross underestimation of the danger that electricity poses for everyone on a job site, even those who may not even be working currently. The following accident analysis discusses that kind of case.
On Aug. 17, 1990, a 53-year-old male was working the 7 a.m.–3 p.m. day shift at a major steel company; he was part of a four-man crew conducting normal daily activities. At about 9:50 a.m., the crew took a break, which was normal operating procedure (due to the hot working environment of the steel company, crew members were allowed a 15-minute break once an hour). The individual walked into the employee lunchroom and sat on a wooden bench to rest and cool off. The bench was placed next to a 30-inch-tall, floor-model air conditioner. A toaster oven for employee use was on top of the air conditioner and was plugged into a 120-volt electrical circuit.
Due to the extreme heat, the worker was sweating profusely; he was wearing a short-sleeve shirt. He rested his right arm on top of the air conditioner. This arm contacted the energized casing of the toaster oven at the same time his right calf was in contact with the grounded air conditioning unit. He began to shake violently, leading a coworker to suspect that he was being shocked. The coworker knocked the toaster oven off the air conditioner, resulting in the plug being disconnected from the receptacle. However, the circuit had been completed, and the current had traveled through the victim and exited his body where his leg was in contact with the grounded casing of the air conditioner.
A coworker laid the victim down on the bench and began pushing on the victim’s chest in an attempt to perform cardiopulmonary resuscitation (CPR), while waiting for the arrival of the plant’s emergency medical service (EMS) team. Arriving on-site about 15–20 minutes later, they provided advanced cardiac life support. The victim received additional treatment from the local EMS, and he was then transported by ambulance to the local emergency room where he was pronounced dead on arrival.
During the investigation, the toaster oven was found to have a nonpolarized plug that had been inversely inserted into a polarized receptacle. This caused a condition known as reverse polarity, which allowed electrical current to flow through the heating element without the switch being turned to the on position; this energized the toaster oven casing.
The cause of death was determined later to be arteriosclerotic cardiovascular disease complicated by electric shock. When the Maryland Occupational Safety and Health Administration (OSHA) compliance officer and National Institute for Occupational Safety and Health (NIOSH) completed their investigations, they made the following recommendations:
• Employers should periodically inspect all areas of the facility for electrical hazards and apply appropriate control measures. These inspections must include nonproduction areas, such as lunchrooms, break rooms, restrooms, and the like. These hazards may be as simple as using nonpolarized plugs or improper grounding of appliances located in these common areas.
• Employers should require that all appliances brought into the facility be tested for electrical integrity by a qualified person before they are placed in common areas and used by employees. This policy should be communicated to all supervisors and workers at the facility.
• Employers should periodically re-evaluate safety programs and reinforce any training that is related to worker recognition, avoidance and reporting of hazards. The investigation revealed that the victim and his coworkers were aware that the toaster oven presented an electrical shock hazard. On a number of occasions, workers—including the victim—had received electrical shocks from it. These incidents, although minor, should have been reported but were not. Simply reporting the indidents might have saved the victim’s life.
• Employers should provide CPR training to all workers, both management and labor. According to the American Heart Association, for best results, CPR should be started within four minutes. Had more employees been properly trained in CPR, this death may have been avoided. The more employees who are trained, the quicker the response time. CPR was initially administered by a coworker whose last CPR training occurred 15 years previous to the incident. The American Heart Association recommends that CPR training be repeated at least annually to ensure employees remember what to do and have the most up-to-date information.
Had at least some of these recommendations been in place on the day of the accident, this individual may have made it home safely instead of being killed.
Hopefully, this case will highlight that electricity can be a danger to everyone that steps foot on the site, not just those who are assigned to work with it.
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 [email protected]. Joe O’Connor edited this article.
About The Author
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 [email protected].