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Technical Documentation for Survey Administration: Questionnaires, Interviews, and Focus Groups. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-7B)



Johanna Zmud


This report describes the occupant evacuation of World Trade Center (WTC) 1 and WTC 2 on September 11, 2001. Multiple sources of information were collected and analyzed: over 1,000 new interviews with survivors (including 803 telephone interviews, 225 face-to-face interviews, and 5 focus groups); over 700 published interviews; 9-1-1 emergency calls; transcripts of emergency communications, historical building design drawings, memoranda, and calculations; formal complaints filed with the Occupational Safety and Health Administration; and other relevant materials. The egress system, including stairwells and elevators, was described and compared to requirement of both contemporary and current code requirements. This report documents the emergency procedures, both as they were designed to be implemented, as well as how they were actually implemented on September 11, 2001.
National Construction Safety Team Act Reports (NIST NCSTAR) - 1-7
Report Number
Created December 1, 2005, Updated February 19, 2017