Occupancy separations and atria

In the past, where the separated-occupancy concept was used, the occupancies needed to be separated by fire barriers. The 2015 edition allows an atrium to serve as an occupancy separation on a story-by-story basis, provided the atrium is separated from other areas by construction equivalent to the requirements for smoke partitions and the use of the provision is permitted by the applicable occupancy chapter (Section 6.1.14.4.6). The doors in the smoke partitions are required to be provided with positive-latching hardware. Lastly, the provisions require that all other requirements for new atria are met.