Flying debris and raging fire from the collapsed World Trade Center towers impacted nearby buildings. Seven hours after the Twin Towers fell, the 47-story WTC building 7 collapsed.
After years of investigations, the National Institute of Standards and Technology (NIST) found that the intense heat on the floor beams and girders weakened a critical support column in WTC Building 7.
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September 11, 2001:
Destruction, Reconstruction, and Monuments
