In the spring, when snow and ice melt, road surfaces dry and air quality in the city deteriorates as traffic and wind stir up the road dust that has accumulated on streets during the winter.
It is estimated that half of the road dust accumulated during winter is caused by studded tyres. Switching to friction tyres is one of the most effective ways of reducing road dust generation. At present, more than 70% of cars use studded tyres in traffic in Helsinki in the winter.
Approximately 40% of city residents suffer from symptoms caused by road dust.
The intensity of the street dust season varies annually, largely due to variations in winter and spring weather conditions. Road dust mainly consists of material detached from the road surface, which is ground up by studded tyres, in particular, and gritting material. Dust is also generated on construction sites.
Road dust rises in the spring
The diagram shows the average daily road dust content in busy areas in the metropolitan area in the spring at normal weather conditions. Although the amount of road dust varies annually, its impact on air quality is clearly visible every spring. When road dust levels exceed limit value levels, air quality has clearly deteriorated.
Helsinki aims to increase the share of friction tyres in urban traffic in Helsinki from the current level of less than 30% to 70% by winter 2030–2031.
Studies show that one of the most effective ways to reduce road dust is to replace studded tyres with friction tyres. In the winter season 2020–2021, around 28% of traffic in Helsinki was driven on friction tyres.