NIST: Fire caused the collapse of WTC 7

摘要

"Uncontrolled building fires-similar to fires experienced in other tall buildings-caused an extraordinary event, the collapse of World Trade Center 7 (WTC 7)," S. Shyam Sunder, lead investigator for the National Institute of Standards and Technology (NIST), reported at a news conference in August. This conclusion was reached, Sunder said, "by reconstructing the building, beam by beam, column by column, connection by connection into a computer model." The investigation results are included in a draft of the report and recommendations available online at http://wtc.nist. gov; NIST was accepting comments on the document up to September 15, 2008. The study took three years to complete.