If you see lightning or hear even a distant rumble of thunder, it’s time to take cover. One of the biggest mistakes people make is not taking shelter soon enough—if you can see lightning, it’s close enough to strike you! Another mistake? Not staying inside long enough. Experts recommend you stay inside at least 30 minutes after the last lightning strike you see.

Lightning kills an average of 67 people per year in the U.S. So far in 2012, there have been 14 reported deaths, and none in Virginia. But this is only part of the story. Did you know only about 10 percent of people who are struck by lightning are killed? The other 90 percent—several hundred people each year—are left with varying levels of disability, from minor injuries to major trauma.

The best place to take shelter is inside a substantial protective structure, grounded with plumbing and electrical, and fully enclosed with a roof, walls, and a floor—like your home or office. Small structures, like the stand-alone restrooms at many public pools, or partially open areas, like carports, picnic pavilions, and baseball dugouts, are not good choices.

If you can’t get to a substantial structure, a car with a metal roof and sides is the next best option. Convertibles, golf carts, and boats without cabins are not considered safe shelters from lightning.

What if you get caught outside and can’t get to a shelter or vehicle? The best thing to do is move to the lowest elevation possible, avoid large open spaces where you’re the tallest object, and stay away from trees and light posts. If you can, crouch down with your feet together, tuck your head to your chest or between your knees, and cover your ears with your hands.

Stay lightning safe this summer: Keep your eye on the weather, try to schedule outdoor activities when you can minimize your risk of storms, and think ahead to what you might do if a storm catches you by surprise.