Why They Knew WTC 7 Would Collapse and Why They Pulled The Firemen Back:
"The major concern at that time at that particular location was number Seven, building number seven, which had taken a big hit from the north tower. When it fell, it ripped steel out from between the third and sixth floors across the facade on Vesey Street. We were concerned that the fires on several floors and the missing steel would result in the building collapsing.
So for the next five or six hours we kept firefighters from working anywhere near that building, which included the whole north side of the World Trade Center complex. Eventually around 5:00 or a little after, building number seven came down." - Chief Frank Fellini
"The biggest decision we had to make on the first day was to clear the area and create a collapse zone around the severely damaged 7 World Trade Center, a 47-story building heavily involved in fire. A number of fire officers and companies assessed the damage to the building. The appraisals indicated that the building's integrity was in serious doubt. I issued the orders to pull back the firefighters and define the collapse zone. It was a critical decision; we could not lose any more firefighters. It took a lot of time to pull everyone out, given the emotionalism of the day, communications difficulties, and the collapse terrain." - Fire Chief Daniel Nigro "Report from the Chief of Department," Fire Engineering, 2002, VOL 155; PART 9, pages 56-59