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Federal Building and Fire Safety Investigation of the World Trade Center Disaster.



S S. Sunder


A major scientifically based investigation of the WTC disaster was completed recently by NIST. The investigations establish the technical causes of building failures and evaluate the technical aspects of response and evacuation. NIST is a neutral investigator, as it is not a regulatory agency and does not issue standards or codes. The primary objectives of the investigation of the WTC disaster were to determine: DT why and how the WTC buildings collapsed after the initial impact of the aircraft DT why the injuries and fatalities were so low or high depending on location DT what were the procedures/practices used in design, construction, operation, and maintenance of the WTC DT which building and fire safety practices, standards, and codes warrant revision. This session will discuss the investigation efforts to make buildings, occupants, and responders safer, specifically: DT Each tower's probable collapse sequence after the aircraft impact and subsequent fires on September 11, 2001 DT The rigorous and detailed methodology used to analyze the aircraft impacts, fire dynamics, structural thermal response, and collapse due to the effects of aircraft impact and fire damage DT The study of evacuation and emergency response that included nearly 1,200 first-person interviews of building occupants, first responders, and families of victims DT Specific recommendations for improvements to building and fire codes, standards, and practices, including improvements to structural integrity, fire protection, building evacuation, and emergency response.
Proceedings Title
Renewing the Urban Landscape. 7th World Congress
Conference Dates
October 16-19, 2005
Conference Location
New York City, NY
Conference Title


high rise buildings, urban habitat, World Trade Center, fire safety, fire investigations, fire investigators, disasters, building collapse, evacuation


Sunder, S. (2005), Federal Building and Fire Safety Investigation of the World Trade Center Disaster., Renewing the Urban Landscape. 7th World Congress, New York City, NY, [online], (Accessed July 13, 2024)


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Created October 16, 2005, Updated February 19, 2017