Road accidents may involve collisions between vehicles of
different weights under a variety of circumstances. It is rare for
vehicles of equal weight to collide. The range of vehicle curb
weights (masses) extends from less than 700 kg (e.g VW Polo) to
over 2,000 kg (e.g. Daimler Benz, S-class). In accordance with the
impact laws of mechanics, the consequences of collision involving
smaller and larger vehicles are mostly more serious for the driver
and passengers of the smaller vehicle. In the past, it has not
always been possible to completely quantify the seriousness of
accidents or the risk of being injured or killed in Germany because
there is no direct link between vehicle mass and the seriousness of
passenger injuries. All that is available at present is a study by
an insurance association based on single accident cases. This
analysis covered front-seat passengers using seat belts as well,
but not only the drivers.
An American study estimates the risk of being killed in an
accident in a small car (subcompact) very generally as being 8
times higher than the risk in a larger vehicle (fullsize car).
Examining cars of different masses and of equal masses involved in
accidents (comparison between vehicles weighing 900 kg and vehicles
weighing 1,600 kg) on the basis of the FARS (Fatal Accident
Reporting System), note a ratio of 2:1 for the risk of being
fatally injured in a small car as against the risk of being fatally
injured in a larger vehicle. However, the results of US studies
cannot always be translated to European conditions, since
America's car population is quite different from the European
on account of the large number of extremely large vehicles on US
roads.
A Swedish study by FOLKSAM Insurance~which also included
single-car accidents~found that drivers of 800 kg vehicles have an
injury frequency twice as high as that of 1,400 kg vehicles.
Following an evaluation of the accident data for
North-Rhine/Westphalia now available for research purposes and
extended to include automotive features, it is now possible to
obtain results for the "compatibility" problem in Germany
and in the car population involved in accidents here. First results
were published in 1991 Safety in Small and Large Passenger Cars.
The study is concerned with the seriousness of injuries focused to
car drivers involved in accidents with on-coming traffic