Breaking Out of a WTC Elevator
The New York Times tells the story of six men who escaped from an express elevator in the World Trade Center by breaking through a sheetrock and tile wall, and walking down an escape stairwell from the 50th floor. One of the men in the elevator was a window washer, so they used the edge of his squeegee to dig through the sheetrock.
Apparently, the wall between the elevator shaft and the bathroom consisted of three one-inch thick layers of sheetrock and tile. The men were able to dig through two layers of sheetrock with the aid of the squeegee edge. This is an amazing story of survival and well worth reading.