rgency systems were knocked out. For several hours, nearly 35,000 occupants were trapped in offices and elevators. Moreover, the center's towers partially filled with cold smoke. These gases rose up through the core and into offices through open stairwell doors and leaking elevators. The building's smoke purge systems weren't capable clearing all floors at once. Obviously, operations at the center' 825-room New York Vista Hotel were severely affected (9:9-15).
After the World Trade Center blast, the quasiautonomous, bistate Port Authority of New York and New Jersey--which owns and operates the towers--instituted numerous safety measures (7:83-84). For example, 1600 battery-powered lights were installed on elevators and stairwell landings. In addition, phosphorescent signs were added to the elevators to mark the location of intercoms. Also, six new satellite fire communications centers equipped with two-way radios, bullhorns, and flashlights were created. These centers are designed to provide the system with redundancy and portability (7:8
...