More than 90% of survivors of the 9/11 terror attacks on the World Trade Center in New York delayed evacuating the buildings in order to carry out tasks such as saving their work, shutting down computers, changing shoes, and visiting the bathroom. Interviews with 271 survivors who worked in the twin towers found that only 8.6% fled as soon as the alarm was raised. The vast majority — 91.4% — stayed behind waiting for information or carrying out at least one additional task, including phoning their families and collecting belongings. The majority delayed their escape by around 8 minutes, with some delaying as much as 30 minutes. People who tried to find out what was going on took between 1.5 and 2.6 times longer to respond to the alarm than those who didn’t. Researchers spent 3½ years interviewing former World Trade Center workers about the day of the attack, generating 6,000 pages of first-hand accounts of what it was like trying to leave the building. The report detailed how congestion on the stairs was the main cause of delay, despite the fact the towers were less than one-third full at the time of the attacks. Of those interviewed, 82% said they stopped at least once during their descent, with a small number stopping more than 20 times. Many were stopped by environmental conditions such as debris, smoke, heat or water on the stairs. Together, their stories paint a comprehensive picture of what happened and why, and what influenced the evacuees’ behavior. Researchers concluded that we need to train people that when you hear an alarm, you need to get out right now. The report has been given to the government for their efforts at improving the safety of tall buildings.
