Walls keep fire contained--if they are there

Firefighters have trouble battling blazes in areas larger than 7,500 square feet. But the Freedom Tower will have the open plan favored by corporate tenants: 35,000 to 52,000 square feet (depending on the floor), broken only by a central corridor. Designers in China have an innovative solution to this conflict between safety and the flexibility businesses require: fireproof partitions housed in the ceiling that lower automatically in case of fire.