Almost people hurt or die because of heavy smoke when the building fires. This is the reason that the current codes in many countries require that the smoke layer in an atrium be maintained above the highest means of egress in the space. The smoke exhaust capacity needed to maintain the smoke layer above the highest level of the means of egress can be substantial if that level is near the top of a tall atrium. In spite of this, there are a number of situations that may affect the effectiveness of a mechanical exhaust system used for atrium smoke management and make this problem to become a real puzzle.
