A TUNNEL COVER FOR A TUNNEL FOR CONTROLLED VENTILATION OF GAS

摘要

A system, in accordance with the invention, relates to ventilating a tunnel 1 in the event of fire or emission of gases or aerosols. The system comprises a tunnel cover 20 and a mobile fan 21. The tunnel cover 20 has an opening 29 through which the fan 21 blows air. This increases the static pressure at th e cover 20, which change the direction of air at a desired direction. One of t he advantages of the invention is that the tunnel cover 20 makes it possible to utilise considerably smaller mobile fans 21 to ventilate a tunnel 1 in the event of fire or emission of gases than when using earlier known techniques.