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Post-Construction Modification to Fire Protection and Life Safety Systems of the World Trade Center Towers. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-1H) ***DRAFT for Public Comments***



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. The purpose of this report is to document the Port Authority of New York and New Jersey guidelines for inspection, repair, and modifications to fire protection and egress systems in WTC 1, 2 and 7. This includes guidelines governing the inspection and upgrading of fire alarm and fire suppression systems; the reapplication of fireproofing; and the upgrading of elevators, hoistways, and elevator lobbies. This report also documents repairs and modifications made to the fire protection and life safety systems on the affected floors of WTC 1 and WTC2.
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, compartments, elevators (lifts), fire alarm systems, fire protection, sprinklers, inspection, interior finishes, egress, pressurization, venting, communication networks
Created September 1, 2005, Updated February 19, 2017