Four years later, there are a host of unanswered questions about the events of 9/11, including the unexplained and unprecedented architectural collapses of three office towers, and the extent of toxicity in the air of Lower Manhattan.
"Why Did WTC 7 Fall? [WTC 7]was...probably the first steel skyscraper anywhere to collapse solely because of fire. We still don't know why...according to FEMA's report on the collapse [the fire hypothesis] "has only a low probability of occurrence."
"How did the twin towers fall? Many FDNY personnel who saw the south tower collapse reported explosions at the lower levels as the top began collapsing. These reports, as well as "squibs" of smoke seen on video of the collapses, have led to theories that the towers were brought down in controlled explosions."
"Conspiracy theorists aren't the only ones who dispute [the official]version: Some fire scientists also take issue with [it]...And the point isn't just historical. The lessons learned from the WTC collapse will inform decisions about the safety of other modern office towers."
FULL STORY: Open and Shut
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