In his paper, presented new and updated datasets for emissions of passenger cars. He distinguishes between vehicle exhaust and non-exhaust emissions and is one of the first to define non-exhaust emissions as a factor of vehicle weight, with the intention of being applied to studies on hybrid and electric vehicles.Simons suggests that PM10 emission factors could be scaled directly to vehicle weight and provides emission factors for tyre, brake and road wear per kg of vehicle weight. For example, tyre, brake and road wear increase by around 50% when comparing a medium(1600 kg) and small (1200 kg) car. Compared to a small car, largecars (2000 kg) emitted more than double the amount of PM10. See