The subway line between Majorstuen station and Nationaltheatret station is located at the western end of the common stretch of Oslo's subway. This is the oldest part of the common stretch and it was completed in 1928.
All five subway lines have to pass through this stretch, and during rush-hour the two underground tracks have one train every two minutes in both directions. The aim of the project was to improve the tunnel safety by installing new smoke ventilators, new markings of escape routes and emergency lighting in the tunnel.
The construction work took two years, and was divided into five phases. As a result of the project this stretch security has been improved in form of faster evacuation of the tunnel, in case of fire or an accident.
Rytec was highly involved in the project from start to finish. The assignment involved project and construction management roles. Rytec was responsible for:
With only a few minor planned exceptions, the project was implemented without affecting the daily operation of the subway. There were strict requirements of the safety during the project, since there were traffic on the stretch during construction.