Location: Norway, Akershus, Drobak/Hurum
Type: HGV Vehicle & tunnel fire
Date: June 2010
The danger to road users was aggravated by the tunnel's safety equipment and emergency preparedness solution not being designed for self-rescue, resulting in several road-users being trapped in the smoke. 25 of 34 road-users managed to self rescue (through the thick smoke). Nine road-users were trapped and later evacuated from the tunnel by assistance from the fire department.
The steep, underwater one tube tunnel have longitudinal ventilation solution with only one rescue tunnel (3480 m from the fire area), without evacuation options beyond tunnel entrances and adequate turning facilities for vehicles, enhanced risk situation considerably and made it difficult to self rescue. Oslofjordtunnel has had 13 fires (including fire June 23, 2011) and three cases of smoke in the vehicle since it was opened in 2000. Ten of the fires were in large vehicles and three in small vehicles.
The Accident Investigation Board in Norway (AIBN) wrote the following in the report from the fire:
The investigation into the fire in the Oslofjord tunnel on 23 June 2011 has shown that the preconditions for the self-rescue principle were absent as a result of the tunnel's safety equipment and emergency preparedness solution, resulting in several road-users being trapped in the smoke. The AIBN points out the lack of a comprehensive assessment of the interaction between information to road-users, safety equipment, ventilation solution/smoke control, firefighting and safe road-user evacuation (self-rescue) as a basis for the tunnel's emergency preparedness plan.
The relevant agencies, the Directorate for Civil Protection and Emergency Planning (DSB) and the Norwegian Public Roads Administration agreed with the AIBN and the Norwegian Public Roads Administration, which started work on improving the Oslo Fjord tunnel. The safety was not adequately taken care of in the Oslofjord tunnel in relation to fire in large vehicles.
Following the fire in 2011, the Norwegian Public Roads Administration, in cooperation with the emergency services, set a goal to be better prepared for the scenarios of the various events that may occur in the tunnel. It was important to make good use of time by detecting fire early, closing the tunnel, alerting emergency agencies, getting early smoke control and initiating alert and evacuation of road users. Furthermore, the Norwegian Public Roads Administration stated that safety equipment should make it easier to evacuate in a smoky tunnel. A continuous led light and 25 self-rescue rooms were installed.
The following measures was implemented in Oslofjordtunnelen after the fire 23 June 2011:
- 25 evacuation space is established by approx. 250 meter intervals
- Entry zones are signposted down to 40 km / h and it is established speed bumps
- The speed limit is reduced to 70 km / h in the tunnel
- Automatic traffic control camera in both directions
- Speed signs in the tunnel is variable , so the speed limit can be adjusted down by event
- There is a ban for heavy vehicles in the tunnel center lane .
- "Turn around and run out " - signs are established at each turning points with 1,500 meters apart . These can be activated from Traffic surveillance as required
- Improved surveillance camera that gives Traffic surveillance overview, even with large amount of smoke
- " Low gear " - signs that are automatically activated by high vehicles
- It is established rumble strips in the tunnel , and " Low gear 'is marked up in the roadway in several places
- Led lights throughout the tunnel is activated by events to lead the people out or to the nearest evacuation facility
This fire was the first of 4 mayor tunnel fires in Norway in the period from 2011 to 2015. The recommendations and the strategy work after these incidents gave a different outcome on a similar fire in 2017 (article: Self-rescue rooms - a success) in the Oslofjord tunnel.
Photo: Arild P. Sovik