Emissions of particulate matter (PM) from motor vehicles originate from two main sources: the exhaust from combustion engines and the degradation of vehicle parts and road surfaces. The latter, comprising all airborne particulate emissions generated by vehicle and road wear and the resuspension of road dust, are defined as non-exhaust PM emissions. The proportion of PM emissions from non-exhaust sources has rapidly increased in recent years due to the significant reductions in exhaust emissions over this period, and are now responsible for about 90% of all PM emissions from road traffic (Timmers and Achten, 2016[1]; Rexeis and Hausberger, 2009[2]).