Numerical analysis on the hazards of open stairwell doors in high-rise residential buildings

Abstract

High-rise buildings have unique risks associated with fire as egress is often limited to stairwells. Protecting these vertical paths from the infiltration of smoke is essential for safe evacuation. Passive fire safety strategies have addressed this by using fire-rated compartmentation. Fire-rated stairwell doors are commonly compromised in residential buildings, as observations have found them propped open or failing to close correctly. Many recent fire tragedies have demonstrated the spread of smoke into the stairwell can render egress paths untenable and carry smoke throughout the building. The consequence of stairwell door openings on smoke spread in high-rise multi-unit residential buildings is evaluated in this study. The smoke spread is predicted within a 10-storey multi-unit residential building using computational fluid dynamics. Tenability predictions in the stairwells determine available safe egress time for an array of leakage and door parameters. This illustrates the relative hazard to egress where stairwell doors are not properly closed.