Are you on the correct forum? You expect facts from us liars?!Real honest to God facts.
http://www.tornadostormshelters.com/Shelter.htm
Read the post where one of the members mentioned doors missing from most of the shelters, including the one he occupied, but there was no sucking like in the movie (ok it's a movie and we know not to believe everything we see in movies). I am certainly glad to know that the doors may not be a critical component. My basement shelter, though it has a slab roof has just a normal stairway down and hollow core door. When this took some water the insurance company sent an engineer out to look at the shelter, his comment to me was it was built like a bomb shelter. Hope it will be safe enough for the weather we get around here.