Stairs in an emergency

Some 911 survivors described getting out of the 60+'th floor by going down the tower stairs, of which there were 4 sets, one per corner. Obviously it took a while to do that, but they'd been required to do drills so they knew what to do and where to go.

It didn't take nearly as long as I'd have guessed, though, given my own experience at Fermilab. The high-rise is only 15 floors. The building looks like an ice cream sandwich that fell and opened up. It also has 4 stairwells, but the atrium set were forbidden during the tornado drill--exposed to flying glass. So during the drill, 15 floors worth of people descended through 2 enclosed stairwells. I was on the 15'th floor. (There's a 16'th too, but almost nobody is there.)

It took about 30 minutes for us all to reach the basement. If a real tornado had been heading at us, it would have caught us with our pants down. I didn't even get into the stairwell for over 10 minutes.

4 times as many floors, and more people...