dr william grosshandler building and fire research laboratory national institute of standards technology us department commerce october 3 2005 federal safety investigation the world trade center disaster international workshop on mutual recognition agreements mra for telecommunications equipment nist wtc objectives determine why how towers collapsed following initial impact aircraft 47 story 7 numbers injuries fatalities were so low or high depending location including technical aspects protection occupant behavior evacuation emergency response procedures practices used in design construction operation maintenance buildings identify specific areas current model codes that warrant revision credit noaa september 23 2001 underground car park total capacity 2000 110 stor ies 1362 f t north 1368 south 6 services skylobby express elevators local plaza level representative elevation open plan office 208 ft
