how many flights of stairs for 9/11

The number of flights of stairs for 9 floors typically depends on the design of the building and local building codes, but generally, each floor corresponds to one flight of stairs. Therefore, for 9 floors, there would usually be about 9 flights of stairs. A flight of stairs usually contains between 12 to 17 steps, depending on ceiling height and other factors. For instance, a 9-foot ceiling often has around 15 to 17 steps per flight. This means climbing 9 floors roughly corresponds to climbing 9 flights of stairs, each having about 15 to 17 steps.