This report covers information from three earlier reports written in Norwegian. The three reports deal with tunnel statistics, analysis of traffic accidents and data on car fires in tunnels. The number of tunnels has increased by 82 during the last four years. The accumulated length of tunnels on the national road network today is almost 600 km. Of the 702 tunnels 405 tunnels are 500 m or shorter and 40 tunnels are longer than 3,000 m. The average AADT in the tunnels is about 3,500. Traffic accidents with personal injury are reported to the police, and local road offices make geographical references to where the accident happened and records the data in the accident data bank (STRAKS). In this accident analysis 588 tunnels opened in 1992 or earlier were studied. In this five year period 499 accidents were recorded. Two thirds of the tunnels had no accidents. Accidents were divided into a zone of 50 m outside the tunnels (zone 1), then the first 50 m of the tunnel (zone 2), then the next 100 m (zone 3), and then the rest of the tunnel (zone 4). 26% of the accidents were recorded in zone 1, 19% in zone 2, 19% in zone 3 and 36% in zone 4. The accident rates (accidents pr year pr 1 mill veh.km) is 0.30 in zone 1, 0.23 in zone 2, 0.16 in zone 3 and 0.10 in zone 4. Accidents in tunnels are somewhat more serious compared to accidents on the open road. Of the different accident types, accidents between vehicles with same direction is overrepresented in one way tunnels, and accidents between meeting vehicles and single vehicles accidents in tunnels with two way traffic. There is no mandatory reporting of fires in Norwegian tunnels. The Public Roads Administration has therefore asked local road offices and fire departments to collect data. This contact gave a record of 41 fires during the last 7 years, 8 fires were initiated by a collision. In 6 cases PolyEthylen-lining material in the tunnels had caught fire. (A)
Abstract