The Effect of Exit Familiarity and Social Influence on Evacuation Behavior
The affiliative hypothesis and familiarity model propose that people tend to evacuate buildings through a familiar exit or with familiar people during an emergency (Sime, 1983). This behavior of ‘moving towards the familiar’ has been observed in case studies, but little experimental research has been done to test this phenomenon. The present study investigates the effect of exit familiarity, combined with the effect of social influence on fire evacuation in two experiments. Immersed in a virtual environment, twenty participants (in each experiment) entered a variety of virtual rooms (7.7 m x 7.7 m) through one of two doors (the familiar door). There were three door configurations and four social influence conditions: after the fire alarm was triggered, the virtual human(s) (VH(s)) exited via the familiar door, the unfamiliar door, remained passive and did not evacuate, or was not present (control condition). Across all trials, participants evacuated via the familiar door significantly more often than via the unfamiliar door. The results also showed that the VH(s) had a significant effect on the participant’s exit choice. Participants chose the familiar door more often in the VH Familiar Exit condition compared to the other experimental conditions and the unfamiliar door more often in the VH Unfamiliar Exit condition compared to the other experimental conditions. The familiarity effect was modulated by the virtual humans’ behavior; this pattern was stronger in Experiment 2 when two virtual humans were present. With this new experimental research, crowd and fire safety engineers can incorporate crowd psychology and affiliative behavior into the development of realistic and efficient evacuation strategies in the future.