Does mobile equipment obstruct the movement of shoppers? Research in the field of fire safety

Most fire safety regulations require that the path to the emergency exit be wide and free of any obstructions in its path. Based on accepted standards, retailers often clear not only the path to the emergency exit, but also the normal, inter-section passageways, which often results in an ineffective retail space.

According to the law, the width of the main evacuation aisles in the sales area must be at least:

1.4 m - for retail area up to 100 m2;
1.6 m - for sales area of 100 to 150 m2;
2,0 m - for the sales area of 150 to 400 m2;
2,5 m - for the sales area of 400 sq.m. and more.

With such standards retail workers often have to give up some of the equipment in favor of visitor safety, which is certainly the right decision, but how do obstacles affect the movement of people in the flow?

How obstacles affect customer traffic

We decided to investigate this issue further and found a very interesting study being conducted by the University of Tokyo in Japan. This study showed that putting obstacles in the way of an emergency exit can help crowds to get out more efficiently. Let's now look at why this might be happening.

So, a team of researchers at the University of Tokyo found that when people follow an object-free emergency path, they clump together into one disorganized mass, where they push each other. These pushes translate into friction, slowing down the speed at which people can get out. Introducing the placement of obstacles on the path to the emergency exit and directly at the exit itself can reduce the number of people moving toward the exit at the same time, increasing the speed at which they can pass.

"We found that we could evacuate faster if we placed obstacles on the way to the exit," said Daiichi Yanagisawa, study leader from the University of Tokyo in Japan.

The researchers began their experiment by virtually simulating large crowds of people at small, unobstructed exits, and then placed obstacles that the crowd needed to overcome to get to the exit. In most cases, the obstacles reduced the number of people able to get out in a minute. Surprisingly, the experiment showed that more people were able to leave in less time when the obstacle was in the path of the emergency exit.

"Contrary to our intuition, the impassability caused by an obstacle, in a certain case, organizes a crowd because it reduces conflict between people moving in the same direction," Yanagisawa said.

Later, the results of the Japanese study were verified by National Geographic. The TV channel conducted an experiment involving 60 volunteers, who on signal exited through a narrow door. As a result of the experiment, the channel found that the behavior of the volunteers completely corresponded to the virtual simulation of the crowd. Similarly, when an obstacle was placed in the way of exit, people exited faster than when the path was completely free.

We have prepared for you a snippet with the experiment itself:

Placement of mobile equipment in the aisles of the sales area

Daiichi Yanagisawa's team was the first to come up with a theory and was able to prove it in hopes of improving fire safety and evacuation methods around the world. The National Geographic TV channel filmed a visual experiment, and even later the theory was tested and proven by the Swedish Royal Institute of Technology, publishing a report.