August 31, 2006

Most studies that have been conducted to test the structural integrity of the Twin Towers, such as last year’s comprehensive report by the National Institute of Standards and Technology (NIST), utilize computer simulation and materials analysis. One British research project, still underway, relies solely on interviews with people who escaped the buildings.

Ed Galea, a professor of fire safety engineering at University of Greenwich, England, oversees HEED, or High-Rise Evacuation Evaluation Database. He is investigating whether or not the World Trade Center buildings were well suited for a quick evacuation, and why evacuees left the building in the manner that they did. The project, funded by a $2.75 million grant from the British Engineering and Physical Sciences Research Council (EPSRC), began in September 2004 and will continue through next year. To date more than 300 interviews have been conducted, and Galea hopes the total will reach 1,000.

“It’s a fairly unique project in that we’re looking at a mix of psychology and engineering,” says Galea, who also is working with scholars from the universities of Ulster and Greenwich. Interview queries broach the processes by which people left the buildings, their reasons for responding to fire alarms at varying speeds, why they might have moved slowly down stairs, and whether or not they yielded to evacuees entering at lower floors, listened to building superintendents’ commands, and considered exiting the building to be a risk. There is no video footage of stairwell evacuation.

Galea says that the results of the study, to be released in November 2007, will encourage faster fire-alarm response and evacuations. He also predicts the research will result in better building codes and more accurate evacuation-simulation software.

The exhaustive interviews can require as much as two hours. Data are broken down into categories such as “response times” and “motivating factors for leaving.” “People in the building who evacuated are the experts,” Galea says; similar investigations, like the NIST effort, use questionnaires, which limit the range of responses. After the project is complete, full interview transcripts as well as researchers’ analysis will be distributed to engineers and made accessible to the public on wtc-evacuation.com. Interview candidates can also consult this site to learn more about participating in the study. 

Sam Lubell