Laborer/rigger electrocuted during an aerial lift of equipment.
NIOSH 2000 Jan; :1-14
A 38-year old laborer/rigger was electrocuted when a cable attached to a helicopter contacted an overhead power transmission line. The laborer/rigger (the victim) and a coworker had completed their assignment of testing new foundation anchors, located below a set of three transmission lines energized to 69 kV. They had just finished moving and attaching rigging cables to two steel beams. The ground crew used a radio in a truck on a nearby access road to request the aerial lift. The transport staging area was 15-20 feet east of the north-south running transmission lines. A helicopter with an attached non-retractable 111-foot cable arrived and hovered. The wind direction was from the east, placing the helicopter upwind from the lines. As the helicopter maintained a heading nearly parallel to the lines, it descended to place the hook and 5-7 feet of the cable on the ground approximately 10 feet south of the load. The co-worker picked up the hook and brought it underneath the helicopter to the beams where the victim was holding the attached rigging cables. Once attached, the co-worker turned to move away from the load and the helicopter. He heard a crack after taking a few steps. He turned and saw the victim stagger away from the beams and collapse. Simultaneously, the helicopter crew heard a crack and saw a flash. The pilot moved the helicopter away from the lines, lifting the load and dropping it nearby. The co-worker then went to assist the victim. Unable to get any response, he ran to a truck to radio for help. Another co-worker standing near the truck went back to the victim and started CPR. After landing the helicopter a short distance away, the pilot exited the aircraft to check the victim's condition. The co-pilot took command of the helicopter and went to retrieve an emergency medical technician (EMT) employed by the company. Several minutes later, the helicopter returned with the EMT. The co-pilot then flew to a refueling area to bring a helicopter with a transport litter to the incident site. The victim was transported to a local medical facility where he was pronounced dead. Based on the findings of the investigation, to prevent similar occurrences, the employer should: 1. Ensure that all aerial lift staging areas are located outside a 20-foot safety zone around overhead power lines and are clearly marked; 2. Ensure that an extended safety zone is used when aerial lifts cannot be done downwind of energized overhead power lines; 3. Ensure that workers are provided with two-way radios for communicating with the helicopter pilot during aerial lifts; 4. Ensure that a spotter is present to provide directions to the helicopter pilot during aerial lift operations and that they (the spotter and pilot) are familiar with both verbal commands and hand signals; 5. Ensure that workers use insulated footwear and gloves while working near power lines; 6. Ensure first aid plans minimize response times during emergencies. In addition, helicopter operators and the helicopter aviation industry should: 1. Consider using non-conductive cables when airlifting loads near overhead power lines; 2. Consider developing and implementing safe operation guidelines for aerial lifts near overhead power lines.
Accident-analysis; Accident-potential; Accident-prevention; Accidents; Injuries; Injury-prevention; Safety-education; Safety-practices; Safety-measures; Traumatic-injuries; Region-10; Work-practices; Work-analysis; Work-environment; Training; Electrical-hazards; Electrical-safety; Electrical-systems; Electricity; Electrocutions; Safety-clothing
Field Studies; Fatality Assessment and Control Evaluation
NTIS Accession No.
National Institute for Occupational Safety and Health
Alaska Department of Health and Social Services