CAR International: a simple model to determine city street air quality

Based on wind tunnel experiments, theoretical considerations and measurements, the dispersion model CAR (calculation of air pollution from road traffic) has been developed for determining air quality in city streets. CAR International, which is a simple parameterized model using readily available input data, calculates annual percentile values and average concentrations close to streets (at the kerbside) for non-reactive air pollutants and NO2. The accuracy of the model has proved to be good and is within the limits set by Dutch air quality decrees. CAR International can be used for a quick survey of city street air quality. It is also a valuable tool for judging the effects of traffic management plans and for scenario studies.