(8:46 a.m.) September 11, 2001: Janitor Hears Explosion from WTC Basement
According to a WTC janitor, there is an explosion in the basement of the North Tower just before the plane hits up above. William Rodriguez has worked at the World Trade Center for 20 years, including the time of the 1993 bombing , and is responsible for cleaning three stairwells in the North Tower. He is talking to his supervisor in an office in the B-1 level in the basement when, he says, “I heard this massive explosion below, on level B-2 or 3.” He says, “The floor vibrated. We were all thrown upwards, then everyone in the office started screaming.” Then, “seconds later, there was another explosion way above, which made the building sway from side to side. And this, we later discovered, was the first plane hitting the North Tower on the 90th floor.”
A man then runs into the office, shouting, “Explosion! Explosion!” The man, Felipe David, had been standing in front of a nearby lift when a fireball had burst from the lift shaft, severely burning him. Rodriguez will later question, “Now you tell me how an explosion from a jet liner could have burnt a man 90 floors down within seconds of impact?”
The National Institute of Standards and Technology will suggest that the basement explosion Rodriguez heard might have been caused by a fireball traveling from the aircraft down the central lift shaft. However, some time after hearing it, Rodriguez rescues two people trapped in a lift. He will therefore doubt NIST’s claim, saying that if it were true, “Why were the two people [I] rescued from the lift not burnt to death?” 
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