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RESEARCH, EDUCATION & MEDICINE // F I E L D M E D I C I N E

a vehicle with a metal top and the windows rolled up is probably the next best option. Contrary to popular belief, it is not the rubber tires that make cars reasonably safe during lightning storms, but the metal structure. When lightning hits a a car, the current is generally able to reach the ground fastest by moving around the sides of the vehicle rather than moving through the inside. Rubber tires could not provide adequate insulation against the 30,000 amps lightning strikes commonly deliver.

If you’re out in the backcountry and cannot get to a building or a vehicle, the safest places to find shelter are among low, rolling hills or in areas of forest where the trees are of roughly equal height. Since lightning is most likely to strike the highest object in a particular area, stay away from open areas to avoid being the tallest object. You don’t want to be close to the tallest object either, so keep away from isolated towers or lone trees as ground current and splash are responsible for the vast majority of lightning injuries. High peaks and exposed ridges are bad places to be. Also keep clear of areas where one type of terrain or ground cover borders another such as shorelines and the edges between forests and fields. Finally, avoid long conductors, too; fences, cables, railroad tracks and even wet ropes can conduct current significant distances. Make sure to consider lightning risk when picking a campsite.

While finding a safe location is the priority when a thunderstorm approaches, there may also be some benefit to getting into a lightning position. Squat down to minimize

your height, and limit your contact with the ground to as small an area as possible. A few feet of height reduction can be sufficient to lower your risk of being struck. Minimize your contact with the ground by keeping your feet close together; this can reduce your risk of being injured by ground current. Some sources advise placing your hands over your ears to reduce the risk of ear injury from blasts. Members of a group should separate at least 50 feet apart to reduce the likelihood of multiple victims. Although lightning position can be uncomfortable, it is best to stay in it when outdoors during a thunderstorm that is within six or eight miles. On a boat, go below decks or, if possible, into the cabin. Avoid tall objects such as masts, outriggers and antennas; these should be lowered if possible and if there is time to do so safely. Move toward the center of the vessel, as far as possible from electrical equipment, the water and anything metal. Stay off the radio unless there is an emergency; if you’re holding the handset, your body may be the shortest path between the antenna and the ground. Some boats, sailboats in particular, are equipped with a lightning protection system designed to act as a conduit for a strike. Such systems reduce the risk of injury to people and damage to the vessel by presenting an unobstructed path from the highest point onboard down through the hull into the water. If a lightning protection system is present, don’t touch any of its components.

Avoid diving or being in the water during a storm. It’s hard not to be the tallest object around if you’re on the water, and current can travel significant distances over

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