Why Building 7 Fell, according to NIST

On Sep. 11, 2001 three skyscrapers collapsed at the World Trade Center complex. The third one was WTC 7 which was not hit by a jet and only after years did the National Institute of Standards and Technology(NIST) address trying to explain why it fell. A high school physics teacher was able to convince NIST that the building fell at free fall speed after they had missed that. What gives? See if you can fathom NIST's explanation as Kathy McGrade, professional career materials scientist, presents a graphic demonstration. Might there be a more plausible explanation for its collapse that NIST is censoring? Got standards?