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A probabilistic approach for the analysis of stair evacuation movement data



Enrico Ronchi, Erica D. Kuligowski, Richard D. Peacock, Paul A. Reneke


This paper presents an innovative method to study stair evacuation data based on a probabilistic analysis of occupant travel paths. This type of approach relies on a detailed video analysis of people movement and pattern reconstruction. Conditional probabilities for the evacuee population are calculated for travel path trajectories on landings, walking speeds, and physical area occupied on stair landings. The present work questions the traditional deterministic methods adopted in stair evacuation calculations by introducing alternative concepts based on probabilities, here termed the probable travel path (PTP), the probable walking speed (PWS) and the probable effective area (PEA). The proposed new concepts have been applied for a case study using data from a stair evacuation drill performed in a six-story building. The evacuation drill was filmed and occupant’s behaviours in stairs have been analysed using the new method. The benefits gained from the use of the new probabilistic approach are discussed, including 1) the identification of the limitations associated with the use of a deterministic approach (e.g., effective width) if compared with the new probabilistic concepts, 2) the possibility to work on evacuation calculation methods directly based on experimental data, i.e., there is no need for modelling assumptions and theoretical hypotheses on travel distances and areas, and 3) a more accurate approach to provide stair evacuation data for model validation studies.
Fire Safety Journal


Stair evacuation, Pedestrian Movement, Probabilistic approach, Effective width, Conditional probabilities


Ronchi, E. , Kuligowski, E. , Peacock, R. and Reneke, P. (2014), A probabilistic approach for the analysis of stair evacuation movement data, Fire Safety Journal, [online], (Accessed July 17, 2024)


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Created January 1, 2014, Updated November 10, 2018