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Fire Protection and Life Safety Provisions Applied to the Design and Construction of WTC 1, 2 and 7 and Post-Construction Provisions Applied After Occupancy. Federal Building and Fire Safety Investigation of the World Trade Center (NIST NCSTAR 1-1D) ***DR



R A. Grill, D A. Johnson


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. To best analyze the performance of WTC 1,2, and 7 in response to the September 11,2001, attacks, the provisions of the design and construction of the buildings must first be understood. The purpose of this report is to summarize the fire protection (both passive and active) and life safety provisions that were used to design and construct WTC 1, 2, and 7 and to document the changes in building code regulations that occurred after their construction. Determination of the applicable building provisions was a multi-step task. First, documentation (such as drawings, memoranda, and New York City building regulations) was analyzed to identify the initial construction provisions at the times of construction of the three buildings. Second, New York City building regulations, published since the time of construction, were analyzed to identify the new and amended building provisions. Third, the building provisions were analyzed to determine their applicability to the building characteristics of WTC 1, 2, and 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 protection, life safety, fire safety, building design, building construction, construction, compartments, elevators (lifts), power supplied, fire alarm systems, sprinklers, inspection, interior finishes, egress, pressurization, vents, communication networks, fire suppression, fire detection
Created September 1, 2005, Updated February 19, 2017