Elevators are not air tight. That is why your ears "pop" when riding up or down in a tall building. Also, all elevators since WWII have an access hatch in the ceiling, (Remove the ceiling panels. It's there), and most have an emergency telephone or intercom.

To me, the biggest problem in getting trapped in an elevator is... where to "go". When Mother Nature calls, you can refuse to answer only so many times. <img src="/images/graemlins/blush.gif" alt="" /> Maybe those Zip-Loc bags we all carry round have other uses.......

.....CLIFF