Emissions from road wear is an important contributor to PM10 concentrations in the Nordic countries. Due to new regulations and an alternative test method for approval, studded tyres on the market presently have stud numbers ranging from 96 to 190 studs per tyre (at 205/55R16). In the present study, the particle generation from studded tyres was tested in the VTI road simulator. The results show that the tyre with the most studs (190) generates significantly higher PM10 levels than all other tyres, whilst the tyre that generates the least mass of inhalable particles has 96 studs and follows the stud number regulations. Increased number of studs and increased stud force significantly increases the concentration of PM10. Temperatures in the tyre, pavement and air as well as relative humidity also have an effect on the particle levels. A calculation example using the NORTRIP emission model demonstrated that the effect of variations in the studded tyre wear on both PM10 - levels and the number of limit value exceedances for the current data set used was significant.
Keywords: Studded tyres, regulation, wear, PM10, NORTRIP.