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Post-Construction Modifications to Fire Protection, Life Safety, and Structural Systems of World Trade Center 7. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-1I) ***DRAFT for Public Comments***



R A. Grill, D A. Johnson, D A. Fanella


This report was prepared to support the analysis of building and fire codes and standards of the National Institute of Standards and Technology World Trade Center (WTC) Investigation. This report was prepared to support the overall objective of determining how and why WTC 7 collapsed. The purpose of this report is to document modifications and/or repairs of the fire protection, life safety, and structural framing systems of WTC 7.
National Construction Safety Team Act Reports (NIST NCSTAR) - 1-1
Report Number


World Trade Center, high rise buildings, building collapse, disasters, terrorists, terrorism, fire safety, fire investigations, construction, fire protection, life safety, structural systems, beams, fire alarm systems, sprinklers, floors, slabs (members), egress, pressurization, communication networks
Created September 1, 2005, Updated February 19, 2017