Inside Knowledge: When lightning strikes
Knowledge Magazine is the official safety magazine of the U.S. Army.

Spring is just weeks away and, as the weather gets warmer, most training activities will move outdoors. Numerous hazards are associated with outdoor training during the spring and summer months, most notably heat injury. Sometimes, however, Soldiers fall victim to a dangerous force of nature - lightning, which is just as lethal as heatstroke but much less predictable.

Of weather-related fatalities, only floods kill more people annually in the United States than lightning. According to the National Oceanic and Atmospheric Administration (NOAA), more than 400 people are stuck by lightning each year. About 60 of those strike victims die, and many more are left with permanent disabilities.

Although each of the U.S. armed forces usually reports some personnel- or equipment-related lightning strikes each year, the Army has the highest casualty rate. Military personnel, especially infantry and artillery Soldiers, are at risk for lightning injury and death due to the nature of their training and operational activities. Many of these activities take place outdoors in all types of weather and within lightning-prone areas such as the southern U.S. and the open deserts of Iraq.

Lightning-related incidents reported in the Army often involve a single strike that causes multiple personnel injuries. This is because exercises and operations frequently involve groups of Soldiers working as teams, and these clusters form a larger target. Examples of incidents where multiple injuries might result include lightning striking metal or wet equipment, flash lightning exploding from a target or lightning currents traveling along the ground.

Here are a couple of examples to illustrate this phenomenon. At Fort Irwin, Calif., three Opposing Force Soldiers were struck by lightning on a hilltop. Several years before that incident, eight Soldiers were injured at Camp Grayling, Mich., when lightning struck some trees 50 feet away. The Soldiers sought shelter under a tarp when the thunderstorm appeared and were hit when the lightning current traveled at ground level to their location.

There's no single action that eliminates the risk of lightning, but you can reduce your probability of being struck by following a few simple rules. For instance, avoid high-elevation areas, open fields, isolated trees, communication towers, flagpoles, open-top vehicles and water during thunderstorms. It doesn't matter if the storm appears to be far away - thunder signals approaching lightning, and you should take cover as quickly as possible.

If a thunderstorm approaches and a building or closed-top vehicle isn't available, seek shelter under the smallest tree in a group of several large trees, but never under a single tree. Stay at least six feet away from the trunk to minimize the risk of a side strike. If you're caught in an open area without trees or other shelter, assume the lightning safety position: crouch with your feet as close together as possible with the heels together and place your hands over your ears. Do not lie flat on the ground!

If you're training or operating in the open and see lightning or hear thunder, use the "30/30 rule" to determine when to seek shelter. When you see lightning, count the seconds between the flash and thunderclap. If it's 30 seconds or less, seek shelter immediately. Then, wait at least 30 minutes after the last thunderclap before leaving your shelter. Don't be fooled by a blue sky, either. About 75 percent of lightning injuries occur very early or very late in a storm's life, and strikes have been recorded from as far away as 56 nautical miles.

Leaders play a vital role in preventing lightning casualties among their Soldiers. During outdoor training missions, they should designate a weather guard to alert personnel of impending bad weather. Leaders also must decide beforehand when to modify or suspend outdoor training and where to seek shelter in the event of thunderstorm activity.

No one can control the weather, but you can control your risk of becoming a lightning casualty. Spring and summer thunderstorms are just around the corner, so be prepared when lightning strikes.

For more information on lightning safety, visit the National Weather Service Web site at www.weather.gov/os/lightning/index.htm.

Page last updated Fri July 22nd, 2011 at 12:16