Findings were recently released in the investigation of a July 2012 Arc Flash Accident in Shakopee, Minn. where four utilities workers were taken to the hospital due to injuries sustained while working on “inadvertently” charged power lines.
It was determined that a series of missteps by the SPU Crew contributed to the power line accident. The lineman were testing an underground power cable to the Shakopee women’s prison when the Arc Flash occurred, badly burning two workers, injuring others and causing a power outage.
Investigators determined that a pole lineman accidentally connected an underground cable to a hot wire instead of a neutral source on the street pole, causing arc flashes at both the pole and a transformer near the prison, where half of the crew was working. The men were not electrocuted; they were burned from the heat of the arc flashes.
An Arc Flash is when a powerful current of electricity leaves its intended path and travels through the air. The energy released during the Arc is destructive and can cause serious damage to both workers and equipment. An Arc Flash can cause severe burns and destruction of skin and tissue. It also can melt or set clothing on fire, causing more burns. The light and sound from an arc flash can cause retina damage and hearing loss. Breathing the molten vaporized gas caused by the Arc Flash event can also cause
damage to the lungs. Shrapnel and debris are also released durning the blast and can cause extensive harm and damage, as well.
To avoid/mitigate the risk of injury during an Arc Flash, crews are supposed to wear special protective clothing and use protective equipment (known in the industry as PPE). Sadly, one bystander told the FOX 9 news crew reporting on the incident that the worker kept repeating, “I should have put it on. Why didn’t I put it on?”
SPU was cited by OSHA for several violations related to the incident. The reasons included: the crew leader did not conduct a hazards briefing before the work commenced the morning of the accident. Crew members failed to wear all the recommended protective gear, which worsened the severity of their injuries. OSHA also concluded the crew did not fully assess the scene before beginning its work.
It is important to note, the procedure was common and the crew was lead by an employee with more than 25 years of experience. Although the crew goes through regular training and safety programs are there and in place, they were off their guard. Two workers did not wear long-sleeved shirts and one who did had his sleeves rolled up and was injured. Only one worker was wearing a protective face shield attached to his hard hat, but he did not have it swung down to protect his face.
The three citations amounted to $9,600 in fines and SPU had to discipline the crew members. Although this fine may seem minor, it is only a small portion of the cost of the damage and injury incurred. The pole lineman, who was working from his utility bucket, is unable to recall what occurred due to memory loss from the accident and the workers injuries were such that they delayed the investigation by months.
All of the injured lineman are back to work (one year later), although one is still on light duty having just returned to work a few weeks ago. He had spent a month in the burn unit at the local hospital just after the incident. Most of the workers suffered burn scars but thankfully, none are on permanent disability.
The accident affected half of the nine-member crew. Thankfully SPU employees cooked meals and took care of the household chores of the affected families as the workers recovered.
SPU Manager John Crooks said, “We don’t want this to happen to anybody else. It was horrible.”