Print version ISSN 0187-6236
European Union Council directive 96/62/EC on ambient air quality assessment and management requires the development of action plans for zones where the concentrations of pollutants in ambient air exceed limit values. In the urban areas the limit values are exceeded, especially due to the traffic. In this paper, we analyzed the temporal variability levels of concentration of NOX, O3 and SO2 in two street canyons. The distribution of concentrations proves that traffic is the most important source of NOX, this pollutant being emitted during running of the vehicle engines. The level of pollution within U2 street is 25% less than U1 street, even though the measured traffic within U2 street is 50% less than within U1 street. This happen because the streets geometry and locations are different.
Keywords : Pollutant concentrations; traffic; urban; meteorological conditions.