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Reconstruction of the Fires in the World Trade Center Towers. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-5) ***DRAFT for Public Comments***



Richard G. Gann, Anthony P. Hamins, Kevin B. McGrattan, George W. Mulholland, Harold E. Nelson, Thomas J. Ohlemiller, William M. Pitts, Kuldeep R. Prasad


The collapses of the World Trade Center towers on September 11, 2001, resulted from a combination of aircraft impact damage and the ensuing fires. This report documents: The information obtained on the factors that affected the nature, duration and location of the fires and how this was obtained; The development and validation of the fire model used to simulate the fires; Descriptions of the most likely fires, as they were reconstructed; and The modeling and validation of the heat transfer from the fires to the buildings' structural members.
National Construction Safety Team Act Reports (NIST NCSTAR) - 1-5
Report Number


World Trade Center, high rise buildings, building collapse, disasters, fire safety, fire investigations, terrorists, terrorism, reconstruction, fire models, validation, fire tests, combustibles, interior finishes, interior furnishings, heat transfer, simulation, thermal response
Created September 1, 2005, Updated February 19, 2017