Did you know you can still be struck by lightning even when the center of a thunderstorm is 10 miles (16 kilometers) away? No place outside is safe when thunderstorms are in your area, according to the National Oceanic & Atmospheric Administration (NOAA) National Weather Service.

“When thunder roars, go indoors,” advises NOAA, adding that if you can hear thunder, lighting is close enough to strike you. Anyone working outdoors needs to immediately move to a substantial building with electricity or plumbing or an enclosed, metal-topped vehicle with windows up, and stay inside that shelter for at least 30 minutes after they hear the last sound of thunder.

If you are caught outside in a thunderstorm with no safe shelter anywhere nearby, immediately get off elevated areas such as hills, mountain ridges or peaks. Get out and away from ponds, lakes and other bodies of water. Never lie on the ground or take shelter under an isolated tree. Also, never use a cliff or rocky overhang for shelter. Finally, stay away from objects that conduct electricity, including wire fences, power lines and windmills.

People who work in open spaces or near tall objects risk being struck by lightning. These include:

  • Loggers,
  • People handling or storing explosives,
  • Heavy equipment operators,
  • Plumbers or pipefitters,
  • Construction and building maintenance workers,
  • Farmers and field laborers,
  • Telecommunication field repair workers, and
  • Power utility field repair workers.

NOAA says that when thunderstorms are threatening, workers should not start any work project that they cannot quickly shut down. Workers need to be proactive by listening to weather forecasts and also watching out for signs of thunderstorms, including high winds, dark clouds, rain, distant thunder or lightning. If these signs are evident, workers should not start tasks that will take significant time to finish.

During thunderstorms, workers are advised to:

  • Stay off or away from anything tall or high, including rooftops, scaffolding, ladders, utility poles, trees and large equipment such as bulldozers, cranes, backhoes, track loaders and tractors.
  • Not touch materials or surfaces that can conduct electricity, including metal scaffolding, metal equipment, utility lines, water, water pipes and plumbing.
  • Leave areas containing explosives or munitions.
  • Call 9-1-1 if a co-worker is struck by lightning. Victims do not carry an electrical charge, so it is safe to approach them afterwards. If the victim isn’t breathing or has no pulse, start cardiopulmonary resuscitation immediately and continue until paramedics arrive.

People working indoors during a thunderstorm are also at risk of being struck by lightning. NOAA says indoor workers should:

  • Stay off corded phones, computers and other electrical equipment that puts them in direct contact with electricity.
  • Avoid using plumbing fixtures, including sinks and faucets.
  • Stay away from windows and doors and off porches.
  • Never lean against concrete walls or lie on concrete floors.