The impact of people with mobility limitations on exit choice

Demographic trends and advances in accessibility have led to more heterogeneous populations in public buildings. While providing accessible evacuation, it may be necessary to direct evacuees to different evacuation paths depending on functional capacity. The presence of people with mobility limitations (e.g., wheelchair users) may affect the evacuation of others, possibly influencing the decision making of neighbouring evacuees. This study investigates how exit choice of people is influenced by the functional capacity of other evacuees and the design of the exit. Virtual Reality was used to design a discrete choice experiment in which participants were exposed to multiple choice situations and a mixed logit model was fitted to the data. Results from 40 participants indicate that exit choice was positively influenced by other people choosing the exit, and a larger effect was found when the other person was a wheelchair user. The design of the exit also influenced the exit choice of the participants. Large inter-person differences existed. Strategies reported by the participants in the subsequent questionnaire included altruistic behaviour. These results can inform fire safety engineers when outlining evacuation strategies and evacuation model users in their assumptions concerning exit choice in building evacuation.