Have you ever tried to find the best escape route from your room to the outside in a big hotel? If so, you’ve probably been a bit confused at one time or another, because neither the escape plan on the room door nor the signs are always clear. The same applies to office and other large buildings. Tim Wächter, a doctoral student at the Institute for Intelligent Buildings (InfinteG) at Bielefeld University of Applied Sciences, Germany, has investigated in his doctoral project how escape route guidance can be improved in the event of a fire and thus save lives.
Currently, escape route signs and plans are focused on showing the shortest route out or to a safe area. However, this escape route may lead straight to the source of the fire. Or it may be blocked and people are trapped. In addition, escape route maps must first be noticed, studied and internalized to have a positive effect, Wächter points out. And even if the correct route is memorized, it can be easy to forget it at the moment of real danger and under stress. Escape route signs that are obscured by thick smoke are then of no help either.
An autonomous system for escape route control
According to Wächter, these issues should not be a problem at all given the current state of technology. With his work, funded entirely by the Ministry of Culture and Science of the State of North Rhine-Westphalia, he would like to contribute to eliminating the shortcomings of a static escape route control system as far as possible. His idea is an autonomous escape route control system “that can access architectural information (for example, lengths and widths of corridors and stairwells) and current sensory information (for example, temperature, carbon dioxide content and light intensity), process it and calculate as quickly as possible which escape route is the best one.”
Since such a building evacuation system could precisely locate the sources of the fire itself, it would always prescribe escape routes that lead around the danger point, explains the computer science graduate. “The escape routes could be indicated with the help of highly visible LED strips in the floor or on the wall, whose wandering light points would indicate the direction of escape.”
But Tim Wächter and Professor Martin Hoffmann, who is supervising him in his research project, would like to go one step further. They want to take other important parameters into account and incorporate them into the algorithm that controls such an intelligent system. “Evaluating the structural conditions of a corridor based on fire safety criteria is very important to be able to analyze escape conditions in as differentiated a manner as possible,” says Wächter, explaining his approach. “For example, steps or poor lighting can significantly impair an escape route. That’s why, together with civil engineers* here at the Minden campus, we have compiled a list of 56 questions covering a wide range of aspects of fire protection. The greater the evaluation value resulting from their assessment, the better the quality of the escape route.”
First prototype has proven itself
An initial prototype for simulating dynamic fire scenes has already proven itself. The system recognized the fire points and selected – for the same escape route length – the route with the better evaluation value. As a result, it performed about ten percent better than the static system. Based on these evaluation values, the dynamic escape route guidance system could probably be improved even further because longer routes are often even better suited for escaping from a building than some shorter ones, according to Wächter. The 28-year-old’s project also focuses on detecting and flexibly responding to temporary obstacles in corridors. These can be baby carriages in large residential buildings or food carts in hospitals “since these significantly reduce the actual assumed capacity of a corridor for people trying to escape.”
To make this escape routing practical, Wächter would also like to work with experts such as fire chiefs in the future. “This holistic approach is important for both sides because it’s the only way an idea that was initially developed in theory can become a major societal benefit – and actually save lives.”