The aim of this project is to arrive at a preliminary indication of how the
use of tyres and traffic safety
were changed when the Law on winter tyres was in force; this Law directs that
cars, light lorries and
buses, of a total weight not exceeding 3.5 tonnes, shall during the period 1
December-31 March, when
travelling on a road, be fitted with winter tyres or similar equipment when
winter road conditions prevail.
This Law came into force on 1 December 1999.
The use of tyres was investigated at parking sites in Östergötland. Apart
from the type of tyre (summer
tyres/winter tyres without studs/winter tyres with studs), the year of
manufacture, tread depth and stud
protrusion were also noted.
The traffic safety effect of the use of different tyres cannot be
investigated directly since information
concerning tyres is not included in accident data. The effect was therefore
investigated by comparing two
winters before the introduction of the Law with two winters when the
requirement concerning winter
tyres was in force. In order to reduce the influence of other changes,
control areas were used. In the north
of Sweden, practically all cars had winter tyres before the Law. There should
therefore be only a small
change in tyre use. Northern Sweden can therefore be used as a control area.
In order that there should
also be a control area in the south, a request was made to Denmark, where
there had also been no change
in tyre use, if it would be possible to utilise data from there. In order
that the effect of the Tyre Law
should be further elucidated, the roads in Sweden where a special winter
speed limit was in force during
the period concerned were also excluded. Southern Sweden up to a line to the
north of the counties of
Bohuslän and Uppland was therefore used as test areas.
Linköping: Statens väg- och transportforskningsinstitut., VTI rapport 479 , 2002.
Swedish, Sweden, Studded tyre, Traffic regulations, Before and after study, Winter, Accident rate, Tyre, Quality, Use, Wear, Icy road