Ant behaviour helps with escape route design

In designing exits that function more effectively during evacuations of large buildings and sporting arenas, engineers have studied the movement of ants. Crowd safety is emerging as an important issue worldwide following numerous incidents in which crowd panic has resulted in injuries and death.

The most recent incident occurred in the Kiss nightclub fire in Brazil earlier this year where 242 people died. In research published in Transportation Research Part C: Emerging technologies, engineers at Monash University in Melbourne used a “bio-inspired approach” to better understand human traffic flow and, potentially, save lives in large-scale emergency situations.

Given the global trend towards mass urbanisation and increasing incidence of mega-events, terrorism and natural disasters, office buildings, railway stations and sports arenas needed to be better designed to provide smooth emergency evacuations, said Dr Majid Sarvi, a co-author of the paper.

“With the large numbers of people who attend events, work in ever increasing tall buildings and use our transport systems, it is important buildings are designed to allow for quick and efficient evacuation should the need arise,” Sarvi said.

In the study with ants, the researchers examined several exit options: in the middle of a wall; at the corner; at the midpoint of a wall with a partial obstruction near the exit; and at the corner with a partial obstruction near the exit. They found the ants evacuated rooms faster when the exits were located in corners rather than in the middle of hallways.

“The location of the exit at the corner was 93.5% more effective in reducing the evacuation time than when the exit was positioned in the middle of the wall,” Sarvi said, adding that the increased effectiveness of the corner exit could be due to the minimisation of conflict points at the evacuation point.

“With the middle exit, ants escaping along both sides of the wall had to change their direction at the exit in order to evacuate. This created conflict with the ants moving straight towards the exit. However, with the corner exit scenario, there were comparatively fewer conflicts with the ants moving straight towards the exit and those escaping from the side walls.”

The researchers then simulated a human evacuation scenario and found the ant model prediction accurately predicted human traffic flow. But they noted that there was a need to further examine the physical and behavioural similarities and dissimilarities among different animals to decide how this could help with design solutions to enhance crowd safety.