WTC risk factors in evacuation

Fascinating piece here on Science Daily about the findings of Columbia University’s Mailman School of Public Health on factors that delayed the evacuation of the World Trade Center on 9/11.

The study concludes that there are three main issues: how long it takes to start the evacuation, how long it takes to complete the evacuation, and whether (and presumably how badly) people are injured.

In the case of the WTC the process of even beginning the evacuation was delayed by lack of awareness about and experience in evacuation procedures; people making phone calls; checking on colleagues; and concerns about one’s own physical ability to make it down multiple flights of stairs.

Sadly,
> Workers also delayed their evacuation because they were waiting for their supervisor’s permission to leave. The length of time for the entire evacuation process was lengthened by inappropriate footwear; confusion about where the staircases were located and where they terminated; and periodic congestion on stairs. Injuries were associated most often with physical disabilities (i.e., those with physical disabilities were more likely to be injured during the evacuation process).

I recall reading an account of an airline crash where those who survived were those who precisely did NOT heed the safety advices about staying calm and forming an orderly queue for the exit — they simply barged their way to the nearest hole in the plane and jumped out, while those queuing in the prescribed manner were mostly burned to death.

Social mores are, of course, the means by which we all live together in confined urban and social spaces. But it seems that they may have limited applicability in life-or-death situations, and it is those who revert to the id fastest who seem to survive.

The other moral of this story is: Wear sensible shoes to work. I’m not kidding.