Wall-following searching or area coverage searching? Simulation study of the panic evacuation considering the guidance of a single rescuer

The guidance strategy for a single rescuer plays a vital role in evacuation management which has yet to be thoroughly studied. Hence, one factor of panic evacuation involving the guidance of a single rescuer is investigated by an extended cellular automaton (CA) model in this paper. The effects of the global panic factor, the hazard position and the environmental familiarity on pedestrians’ evacuation under different guidance strategies are discussed. The analysis of simulation results demonstrates that the panic makes a great impact on the pedestrians’ evacuation process and their sensitivity to hazards increases consequently. When pedestrians’ panic degree is relatively high, a wall-following searching (WFS) strategy should be adopted by a rescuer, otherwise an area coverage searching (ACS) strategy is a good choice. In addition, the position of the hazard hitting in the room significantly affects the pedestrians’ panic evacuation process. When the hazard position is closer to the exit, the evacuation time lengthens without a rescuer present. Both ACS strategy and WFS strategy are helpful to increase the evacuation efficiency wherever the hazard is located, and WFS strategy works better. Furthermore, the pedestrians’ environmental familiarity has a greater impact on their evacuation process. The better the environmental familiarity, the faster the pedestrian flow rate is. In the early stage of evacuation, the pedestrian flow rate is higher under the ACS strategy, while in the later period, the rate is higher under WFS strategy. For the entire stage of the evacuation, WFS strategy is always more useful than ACS strategy whether evacuees are familiar with the room or not. The study contributes to understanding the importance of the guidance strategy in pedestrians’ evacuation and to developing an efficient evacuation strategy for evacuation management.