Here is a product that can be used to greatly reduce or eliminate the need for a smoke control system in an atrium. In section 404 of your building code you will find that it states when an atrium is three stories or more it is required to have a smoke control system.
In this case the architect chose to use this textile enclosure strategy to reduce the amount of air volume exhausted from the atria. By having one of these fire rated enclosures positioned to deploy just on the third floor they were able to save a significant amount of money and time in mechanical ductwork, controls and equipment.
The stairway that was included in the three story atrium was not an issue in this case either because anyone in the stairway could easily exit by continuing down the stairs to an exit floor. Foldable curtains like these can be designed in intricate shapes and protect very unique spaces. In this example the smoke curtain has seven sides with various angles to make a complete enclosure. It takes up very little space in the ceiling and only comes down if there’s an actual fire where smoke is detected in the building.
Most visitors that come into this building will not even know there is a fire rated smoke curtain secretly positioned above the ceiling for their safety in the event of a fire emergency. It’s unobtrusive and extremely effective. If you’d like more information about atrium smoke control or textile enclosures like this one please feel free to contact me.