Report on three winter accidents, 18 March 2008
Road traffic report 2008/02
The Accident Investigation Board Norway (AIBN) has investigated three road traffic accidents with fatal outcomes. All three accidents occurred during the winter 2005-2006. The investigations are documented in three separate reports (VEI Rapport 2007/02, VEI Rapport 2008/03, VEI Rapport 2008/04). In all three accidents one light vehicle skidded on winter road conditions, and went into the opposite traffic lane where it collided with an oncoming heavy vehicle.
The quality and effort level of the winter maintenance is vital to obtaining the best possible driving conditions and safety margins during winter time. This theme investigation has revealed that the Norwegian Public Roads Administration (NPRA) lacks sufficient quality assurance of the winter maintenance with regards to traffic safety. The theme investigation points to improvement potential within the following safety critical elements concerning winter maintenance of the road network (especially for busy and accident exposed roads):
1. The NPRA should determine the standard for winter maintenance based on safety analyses of specific road-sections.
2. The NPRA should establish systems for safety evaluation of the contractors` operations and plans before signing the contract to ensure that the maintenance functional contracts` requirements for traffic safety during winter time (winter standard) can be fulfilled.
3. The NPRA should improve the system for ensuring that the contractor meets the requirements for traffic safety during winter time (winter standard) in the maintenance functional contract.
4. If ordinary maintenance of the roads (ploughing and salting) do not provide an acceptable safety limit, the NPRA should consider alternative safety measures and the use of traffic information about the reduced driving conditions.
The investigated winter accidents show that both different vehicles and drivers cope differently with reduced driving conditions, and situations arise where those with the least safety margins loose control. In all three accidents the light vehicles were equipped with unfavourable tyres in relation to the road surface conditions. It is uncertain to what extent the road-users were aware of the increased risk on reduced driving conditions. Therefore, it is a potential for improving traffic safety through increased information to the road-users in this connection, especially the importance of tyre equipment related to driving conditions. The AIBN believes that Electronic Stability Control in combination with good tyre equipment adjusted to the driving conditions will raise the safety margins considerably for vehicles. Presence and control in the traffic could also influence and manage the road-users` behaviour and speed.
As a result of this investigation, the AIBN has made five safety recommendations.
Facts
| Location | Three winter accidents |
| Occurrence date | 18.03.2008 |
| Accident type | Thematic investigation |
| Vehicle type | Bus or coach, Lorry, Passenger car, Van, Truck and trailer |