Fire safety and evacuation

Technical features

On the line between Ullevål and Storo, fire safety systems are in place mainly to prevent fire outbreak in tunnel and channel sections and at Nydalen station.

Nydalen station: Fire loading at the station is defined by the fire loading potential of the Metro trains in use. Smoke in the station hall is automatically detected by line optical smoke detectors. The ventilation system, with its 8 fans, is triggered depending on where the smoke is detected. The fans are dimensioned to extract 350,000 cubic metres of air per hour. The ventilation system opens to full effect within 90 seconds and provides visibility longer than stipulated by prevailing safety regulations. The extraction system is fitted above the tracks in the station hall, in combination with supply air from the tunnel. Fire safety procedures are dimensioned to manage the evacuation of 900 persons from the station. The station is fitted with an automatic audio warning system that requests commuters to leave the station in case of emergency.

In tunnels and channels: Risk of fire in the tunnels is potentially based on the amount of wiring laid down along the track. Halogen-free cables that do not emit poisonous gases if they catch fire, are stored and protected in a sealed concrete cable track. General safety procedures in the Metro for smoke emission on trains make sure the trains do not come to a standstill, but travel on to the nearest train station where passengers can be evacuated.

In the event of a shutdown that leads to the evacuation of a train in a tunnel, walkways have been installed on the wiring channel that runs alongside the tunnel wall. Controlled evacuation can only occur once the traffic control centre has shut down the power to the running rail and turned on the standard tunnel lighting. The tunnels arealso fitted with emergency lighting in case the main power supply is cut. Distances to tunnel openings/exits are signposted every 90 metres on both tunnel walls. The longest distance to an opening is 780 metres.

An emergency exit has been installed in the channel between Nydalen and Storo that leads up to ground level.