Fire Safety Science Digital Archive

This paper presents a simplified reliability assessment of vertical egress provisions in high-rise residential buildings (height >25 m). The assessment evaluates the impact of the building’s height, floor area and external assistance on the resulting fire risk to occupants and relates the required egress reliability to the tolerable societal risk from fire in buildings. The applied assessment puts the problem of egress reliability into perspective by developing relationships on which performance-based alternative design solutions in residential high-rise buildings can be formulated. This paper also assesses some frequently used precautions and evaluates them in the format that permits their comparison against the risk-based acceptance criteria, or alternatively – if such are not practical - against the prescriptive solutions. The potential difficulties are discussed with some such precautions and advice is provided on how to avoid them. The paper aims at improving understanding of the egress problem in high-rise buildings to facilitate performance-based building design.