Exploring the Influence of Emergency Broadcasts on Human Evacuation Behavior during Building Emergencies Using Virtual Reality Technology

Abstract

Emergency broadcasts are one of the most widely used measures to disseminate emergency information among building occupants and guide their evacuation behaviors during building emergencies. This study aimed to assess the effectiveness of emergency broadcasts in information dissemination and behavioral intervention during a building evacuation, with the presence of competing and even conflicting sources of information. Moreover, it aimed to examine whether and how such effects of the emergency broadcast are influenced by its two attributes, namely, the speed rate at which it is broadcasted and the amount of information embedded in it. To achieve these goals, a virtual reality (VR)-based experiment was conducted in which the participants needed to evacuate from a virtual metro station when a fire broke out in the station. During the evacuation, the participants could hear emergency broadcasts that contained different amounts of information and were broadcasted at different speech rates. The results showed that the large majority of participants who received and understood the information conveyed by the emergency broadcast made their wayfinding decisions based on this information, even when it contrasted with their own prior spatial knowledge about the station. The participants also reported in a postexperiment questionnaire that the information conveyed by the emergency broadcast was more important than other sources of information, such as spatial memory and visual cues, for them to complete the evacuation task. In addition, the results revealed that the speech rate affected the participants’ skin conductance level and perceived sense of caution while not causing a significant difference in their wayfinding decision-making or evacuation performance. The amount of information, on the other hand, significantly affected participants’ wayfinding decision-making and evacuation performance. The information overload phenomenon was observed, which negatively impacted how the participants perceived and responded to the emergency broadcast. These findings are expected to advance the understanding of the role that emergency broadcast plays in building emergency evacuation. The implications of these findings to building emergency management practices are also discussed in the paper.