The release of the revised report on the original Seven World Trade Center in New York City marks the end of the $16-million investigation into the World Trade Center. The investigation was triggered by the destruction of the complex on Sept. 11, 2001, by terrorists.
Based on feedback, Gaithersburg, Md.-based National Institute of Standards and Technology made several changes to the draft final report on the 47-story steel-framed tower, which collapsed on Sept. 11 after burning unattended for some seven hours. The report was released for public comment on Aug. 21. The revisions did not alter the investigation team’s major findings. According to NIST, the fire heated floor beams and girders, causing a critical column to fail.