by Rich McCrea
Exposure to lightning during firefighting is very common, and there really is no place in the outdoors that is safe when a thunderstorm is in the area.
Wildland firefighters are especially more susceptible to being struck by lightning since they work long shifts outdoors during hot weather, when thunderstorms usually occur. Fire crews spend a great deal of time working or traveling along ridge tops, which can increase the exposure to lightning hazards.
Firefighters also carry a variety of metal objects including hand tools, chainsaws, radios and other items. Long metal objects, in particular, are very good conductors of electricity; there is additional danger in carrying small metal objects, which can cause burns if a person is impacted by a lightning strike. In addition, fire crews also work around large metal objects such as vehicles, water pumps, helicopters and dozers. Even a wet rope can conduct electricity from a lightning strike and can be regarded as the equivalent risk to a metal wire.
A LOOK AT LIGHTNING
Lightning is an electrostatic discharge accompanied by thunder, which occurs during thunderstorms, and sometimes during dust storms and volcanic eruptions. A bolt of lightning can travel at speeds of 140,000 mph and reach temperatures approaching 54,000°F. Lightning strikes fast, and the entire process can take less than one-tenth of a second.
Lightning usually strikes directly below the base of a thunderstorm, but many strikes occur well away from the storm and the shaft of rain. This is a real safety concern because you don’t have to be directly under the cloud to be in danger.
A lightning strike typically hits a primary target, and the electric current dissipates through the ground. Generally, a lightning strike is hazardous out to roughly 30 feet from the strike point. Some people occasionally get injured 50 to 100 feet from a strike.
SMART MOVES
Lightning injuries are caused by electrical shock, secondary heat production and explosive force [reference 1]. Electric currents can affect the heart or breathing. The heart will often restart itself, but it takes longer for a person’s breathing to recover.
If you are caught in a lightning storm and cannot move to a safe refuge, remember the “lightning position.” Put your feet together to reduce the effects of ground current, and crouch down to slightly reduce the effects of a lightning bolt actually striking you. Avoid the prone position. The lightning position reduces your chances of being injured, but the best course of action is to move to safer ground or a structure or vehicle when you hear thunder. If you are in a group, have everyone spread apart at least 20 feet to reduce the chances of multiple injuries.
To reduce risk during lightning storms, there are some basic steps fire crews should take. These include:
- Obtain fire weather forecasts that include the possibility of lightning storms at the beginning of your shift. Arrange your schedule during the day to avoid high risk areas, if possible.
- Post a lookout to watch for thunderstorms, as needed.
- Find safer terrain if you hear thunder.
- Stay away from trees and long conductors once lightning gets close.
- Get in the lightning position if lightning is striking nearby.
- Move away from metal objects such as dozers, fire tools, chainsaws and pumps.
Wildland fire managers need to become well-versed in lightning hazards, methods of avoiding these hazards, potential injuries that may result from being struck and first aid for victims. For more information concerning managing lightning risk, review “Backcountry Lightning Risk Management,” a good source of information written by Dr. John Gookin of the National Outdoor Leadership School [reference 2].
References
1 Cooper, M.A., Andrews, C.J., Holle, R.L., “Lightning Injuries,” Wilderness Medicine, 5th ed., 2007.
2 Gookin, John, “Backcountry Lightning Risk Management,” presented at the 21st International Lightning Detection Conference, Orlando, Florida, April 19—20, 2010. Read and download Dr. John Gookin’s guide to  “Backcountry Lightning Risk Management”.
About the Author
Rich McCrea works as a wildland fire management consultant. Outfitted with a BS in Forestry, he started his career as a seasonal employee with the Forest Service, and then moved on to permanent positions with the Bureau of Indian Affairs as a Fire Management Officer. In 2008 Rich retired from the federal government after a 32 year career in fire.
