Trafikverket is conducting in-depth studies on all fatal accidents that occur on the roads. The knowledge from the in-depth studies is used as basic input for raising the level of road safety.
In-depth studies offer an insight into why the accident was so serious that someone was killed. An important starting point for the in-depth studies is to map-out the series of events that resulted in the fatal injuries. Where could the chain have been broken?
The purpose of in-depth studies is to obtain as clear an impression as possible of what happened before, during and after the accident occurred. All information is compiled and analysed by experts at Trafikverket, skilled in vehicle mechanics, road design, trafﬁc engineering and behavioural science. Investigators could also call on experts from the health services, police, emergency services and local authorities.
Trafikverket and other authorities and organisations use the knowledge from the studies for raising the level of road safety.
In-depth studies often lead to immediate changes to the road environment. Guard rails are erected near dangerous roadside areas. Forest areas are cleared on roads with poor visibility. Rocks and trees near roads are removed. Median guardrails are erected. Road signs that impair visibility are moved. Speed limits are reduced at junctions.
One important result of the in-depth studies has been the documentation of the effects of alcohol and drugs. Previously, there had only been suspicions that many drivers were under the inﬂ uence of alcohol or drugs. The in-depth studies provided concrete proof that about a quarter of drivers involved in accidents are under the inﬂuence of drugs or alcohol. This has led to an increase in efforts to stop drunk driving and to encourage the use of alcohol ignition interlocks.
The in-depth studies have also increased awareness of the protection offered by belts and other safety equipment in vehicles.
The work on in-depth studies of accidents started in 1997.