Abstract
It is well known that studded tyres abrade asphaltic surfacings. In Norway, wear is considered significant when AADT exceeds 2-3000. Every year, 250-300,000 tonnes asphalt worth NK 250m are worn away. 2% of the dust is <36 um and floats in the air. Less than 0.5% is <10 um and respirable (PM10). An analysis of the latter shows that particle concentration in this has some significance for health. On dry day PM10 values exceed daily means which have shown to cause reduced lung function in susceptible people. Values up to 500 ug/m3 have been measured. Proposed limiting value (24h) for PM10 is 70 ug/m3. From 1992 studs of lighter weight are used.