Norwegian researchers use audio beacons to help people escape smoke-filled tunnels

If you’re in a road tunnel and you’re suddenly filled with smoke because of a car fire, it’s hard to know where to go,media reported. That’s what EvacSound does, because it uses audio beacons to guide people to safety.

Norwegian researchers use audio beacons to help people escape smoke-filled tunnels

Many road tunnels are located in remote mountainous areas. As a result, it may take some time for rescuers to reach the scene in the event of a fire. Even if rescuers arrive, their paths may be blocked by burning vehicles in the tunnel. This means that it would be nice if the drivers in the tunnel could get out on their own as soon as possible.

EvacSound is expected to help achieve this.

The system is currently being designed by a team led by Tron Vedul Tronstad at the SINTEF Institute in Norway. It consists of a series of speakers placed along the length of the tunnel, which in turn make sounds that guide people away from the fire and toward the end of the tunnel. Importantly, these sounds are non-verbal, so language does not become an obstacle.

Norwegian researchers use audio beacons to help people escape smoke-filled tunnels

In testing the system, 30 volunteers were taken to a tunnel in Trondham, Norway, and put on a pair of tape-striped goggles to simulate low visibility caused by smoke. Their task was then to find their way out of the tunnel — first, they looked for exits under the guidance of audio beacons, and then in the absence of sound beacons, which were known to come from loudspeakers 20 meters apart. To make the picture more realistic, the sound of a smoke removal fan has also been added to the test site.

The study found that while the system did help the subjects get out of the tunnel quickly, it was most effective for young participants. This may be due to some loss of hearing as people age, suggesting that EvacSound sound may work best when combined with visual signals.