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Structural Fire Response and Probable Collapse Sequence of World Trade Center Building 7 (Volume 2). Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-9) ***DRAFT for Public Comments***



Therese P. McAllister, Richard G. Gann, Jason D. Averill, John L. Gross, William L. Grosshandler, James R. Lawson, Kevin B. McGrattan, William M. Pitts, Kuldeep R. Prasad, Fahim Sadek, Harold E. Nelson


This is the primary technical report on the National Institute of Standards and Technology (NIST) investigation of the collapse of World Trade Center Building 7 (WTC 7), conducted under the National Construction Safety Team Act. The investigation objectives were to determine (1) why and how WTC 7 collapsed, (2) all technical aspects of fire protection, occupant behavior, evacuation, and emergency response, (3) what practices and procedures were used in the design construction, operation and maintenance of WTC 7, and (4) areas in current building and fire codes, standards, and practices that warrant revision. Objectives 1, 2, and 3 are addressed in this report. Objective 4 is addressed in the WTC 7 summary report, NIST NCSTAR 1-1A. This report provides technical details of all aspects of the investigation.
National Construction Safety Team Act Reports (NIST NCSTAR) - 1-9
Report Number


building evacuation, emergency response, fire safety, structural collapse, tall buildings World Trade Center
Created August 1, 2008, Updated February 19, 2017