Your car plunges into a river.
Wrong response: Wait until the water pressure is equalized, when water has covered the door, before trying to get out.
Smart move: Every minute is precious, so don't wait, says Pete Gannon, president of Dive Rescue International, which provides water-rescue training. As soon as you hit the water, unfasten your seat belt and try to open a door or window. Even if you have power windows and automatic door locks, hit the button, because they'll probably still open for a few minutes. If you can't open anything, focus on breaking a window by hitting it in the corner. "Most car windows are tempered, so if you hit them in the corner, they will shatter into small pieces," says Gannon. Use a hard shoe, a soda bottle, one key poking out of your fist, or, better yet, keep a small LifeHammer (which can also cut seat belts off) in your glove compartment. It's true that it will be easier to open the door once the pressure has equalized, but it could be too late or the door could be jammed.