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Driller's helper electrocuted when mast of drill rig contacted overhead power lines.

Alaska Department of Health and Social Services
Morgantown, WV: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, FACE 99AK019, 2000 Jul; :1-12
On June 17, 1999, a 32-year-old male drill truck operator's helper (the victim) was electrocuted when the mast of a drill rig contacted two-7,200-volt overhead power lines. The victim was assisting a drill rig operator to drill for a local environmental engineering contractor. They had relocated the truck to the front of an industrial lot to drill the last hole. A small flag indicating the well's position marked the location. The marker was near a fence separating the lot from an adjacent road. Above the marker were four power lines that ran parallel to the road. After extending the truck's front outrigger, the operator began raising the drill rig mast to position it over the marker. The victim was standing near the rear of the driver's side of the truck unloading equipment when the mast contacted the high voltage power line. Two workers employed by the contractor were standing several feet from the driver's side of the truck and heard a noise. They saw the victim and the operator frozen to and then collapse away from the truck. One worker went into a nearby building to call 911 as the other worker went to check both men. A worker from the building and a passerby arrived at the site as the first worker returned. Two teams were coordinated and CPR was started on the victim and operator. Emergency medical services arrived minutes later. The victim and the operator were transported to a nearby medical center where the victim was pronounced dead. The operator survived, but was unable to recall details of the incident. Based on the findings of the investigation, to prevent similar occurrences, employers should: 1. Ensure that a hazard assessment has been completed to identify all hazardous conditions that may affect operation of equipment; 2. Ensure that equipment is not operated where any part is within 20 feet of electric power lines unless the lines have been de-energized and either grounded or insulation barriers have been installed; and, 3. Ensure that a safety checklist is included in the written standard operating procedures (SOP) and is used prior to the start of any drill activity for each work site. In addition, all companies responsible for marking drill sites should: 1. Maintain a minimum 20-foot safety zone and be knowledgeable of all applicable OSHA requirements for work near utilities and electric power supplies; and, 2. Communicate to all parties involved in drilling activities the location of both above and below ground utility and electric power supplies near a drill marker that are within a distance equal to the height or extension of the drill equipment plus 20 feet. To help prevent or reduce the severity of injury in emergency situations, all drill rig owners and operators should ensure that all operator's controls are in good working condition and are clearly labeled.
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
Publication Date
Document Type
Field Studies; Fatality Assessment and Control Evaluation
Funding Type
Cooperative Agreement
Fiscal Year
NTIS Accession No.
NTIS Price
Identifying No.
FACE-99AK019; Cooperative-Agreement-Number-U60-CCU-007089
SIC Code
Source Name
National Institute for Occupational Safety and Health
Performing Organization
Alaska Department of Health and Social Services
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division