Why do people make risky decisions during a fire evacuation? Study on the effect of smoke level, individual risk preference, and neighbor behavior

People make risky decisions during fire evacuations such as moving through smoke. However, the reasons behind such risk-taking decisions have not been investigated in controlled experiments. Using an immersive virtual reality (VR)-based controlled experiment, this study investigated the effect of smoke level, individual risk preference, and neighbor behavior on individual risky decisions to take a smoky shortcut for evacuations. In the present experiment, participants’ risk tolerance was measured using questionnaires, and their route choices were recorded when they evacuated from a virtual building under different smoke scenarios. A high density of smoke reduced the use of a smoky shortcut but did not prevent some participants from using the shortcut. Participants with high-risk tolerance were more likely to take a risky shortcut. However, individual attitude towards risk is unstable; hence, the risk preference revealed in daily behaviors under a low-danger context may not reveal individual risky decisions in face of high hazards. Moreover, neighbor behavior also had a significant impact on participants’ risky decisions. The implications of our findings on evacuation training and management and evacuation simulation models were also discussed. © 2021