High air pollution in vehicle cabins due to traffic nanoparticle emission exposure and a solution for in-use vehicles

Vehicles operating in dense traffic take their cabin air from the low diluted exhaust gas cloud produced by other cars or trucks running ahead of them. They usually take it at a low level where the particle concentration and the concentration of heavy gases like NO2 are still high. Cabin air is thus collecting and storing emission peaks and air pollution in car cabins can therefore be extremely high - often ten times higher than even at roadside. Drivers commuting in big cities, taxi drivers, truckers and school buses might be exposed to this high pollution for several hours per working day, a group put at very high health risk.

Cabin air of today's vehicles usually passes a filter, but these filters are designed for visible road dust and pollen and according to the existing standards filtration of particles < 1 μm is very low. Lung penetration however, only starts < 0.5 μm. In the long run this could be changed by installing different filter systems, but what about the existing fleet? A filter system has been developed to reduce the concentration of ambient ultrafine particles in vehicle cabin air of in-use vehicles to very low levels, which is presented here.