reporter: this video of moore tornado was taken through a crack in one of these. a safe room. researchers have shown us that houses can t show up to tornado wind. safe rooms above ground built into your house or underground in the backyard can save your life. the safe rooms are subjected to their own tests to with stand winds up to 250 mile an hour. canon fired wood. one company dropped bricks, lumber and a car on its shelter. there are above ground and below storm shelters that offer near absolute occupant protection from the worst case tornado. reporter: many homes don t have basements because of loose clay soil or they flood easily. they have doors that open inward, making is easier to be opened by debris. many schools have no safe rooms. right now only alabama requires