The World Trade Center evacuation study: Factors associated with initiation and length of time for evacuation

Robyn R.M. Gershon, Lori A. Magda, Halley E.M. Riley, Martin F. Sherman

Research output: Contribution to journalArticlepeer-review


On 11 September 2001, one of the largest workplace evacuations in the U.S. history took place. The evacuation was largely successful: an estimated 87% of all occupants in World Trade Center (WTC) Towers 1 and 2 exited in less than two hours. Evacuation times, however, were highly variable and not entirely explained by the engineering parameters of the buildings. To understand the complexity of factors that potentially influenced the evacuation time on 11 September, 2001, an interdisciplinary research study was conducted by public health scientists from the Mailman School of Public Health at the Columbia University in the New York City. Analysis of survey data collected from a sample of 1444 evacuees identified several facilitators and barriers to length of time to initiate and fully evacuate from WTC Towers 1 and 2. At the individual level, these included sociodemographic and occupational variables, health status, sensory cues, risk perception, delaying behaviors, and following a group or an emergent leader. At the organizational level, factors included emergency preparedness safety climate variables. Structural (environmental) factors included egress route barriers, poor signage, congestion, and communication system failures. Many factors identified in the study are modifiable. Therefore, these data have the potential to inform high-rise preparedness and response policies and procedures.

Original languageEnglish (US)
Pages (from-to)481-500
Number of pages20
JournalFire and Materials
Issue number5-6
StatePublished - Aug 2012


  • emergency preparedness
  • evacuation time
  • high-rise evacuation
  • organizational safety climate
  • pre-evacuation delay

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • General Chemistry
  • Polymers and Plastics
  • Metals and Alloys


Dive into the research topics of 'The World Trade Center evacuation study: Factors associated with initiation and length of time for evacuation'. Together they form a unique fingerprint.

Cite this