Practice ladder safety near overhead power lines

March 1, 2010

Between 1992 and 2005 at least 154 workers were killed by electrocution when a metal ladder came into contact with overhead power wires, according to the most recent data available from the Bureau of Labor Statistics. NIOSH offers the following advice to employers and workers to help prevent such accidents.


  • Initial worksite surveys should include locating and identifying all overhead power lines. The heights of the wires and distance from the worksite should be noted on site diagrams so workers and supervisors are aware.
  • If work must be done near energized lines, contact the local utility company for assistance.
  • Ensure all workers keep conductive materials 10 feet away from unguarded, energized lines up to 50 kilovolts. For every 10 kV over 50, increase distance by an additional 4 inches of clearance.
  • Do not allow use of metal ladders in dangerous situations – provide appropriate American National Standards Institute-approved ladders for work near energized power lines.
  • Train all workers in emergency communication and proper techniques for providing aid to someone after an electrical accident.


  • Assume all power lines are energized; do not use metal ladders near them.
  • Follow the 1:4 rule: For every 4 feet between the ground and the peak of the ladder, set the ladder feet out 1 foot. For example, a ladder reaching 16 feet should be 4 feet from the edge.
  • Never touch or go near a person or equipment that is in contact with an overhead power line.