The influence of traffic emission on IAQ, especially in street canyons

Traffic emissions have a significant impact on urban air quality, which particularly concerns street canyons, i.e. spaces with limited air exchange. Traffic emissions in street canyons create high concentrations of air pollutants. Based on measurements carried out for selected routes and model experiments conducted in a wind tunnel, it is shown that a roadway’s urban structure has a significant impact on concentrations of pollutants from traffic emission which enter buildings by means of mechanical and natural ventilation systems. In the case of buildings in a narrow street canyon pollution concentrations close to ventilation air intakes may be several times higher than in buildings in wide roadways. The paper also describes a possibility of identifying building surfaces that are particularly exposed to being infiltrated by traffic pollutants from adjacent streets.