Modeling Pressurized Stairwells with Open Doors

Abstract

Stairwells are essential to occupant exiting from tall (high-rise) buildings. In order to maintain tenable environments in the stairwells, modeling building and fire codes allow the use of a stair pressurization system to pressurize the shaft in order to keep smoke and toxic gases from entering the exit stairwell. Thus, allowing building occupants to exit the facility in a safe manner. Model building and fire codes require that stair pressurization systems are sized for all stairwell doors being closed, when during an actual emergency one or multiple doors could be open for various periods of time during a building evacuation. This research project will look at the impact of open stairwell doors on the stair pressurization system fan size based on experimental criteria reported in two American Society of Heating Refrigerating and Air Conditioning Engineers (ASHRAE) projects, RP-1203 and RP-1447, along with some additional modeling methods.