In the framework of an Environmental Impact Assessment of new developments in the Hong Kong Territory wind-tunnel, experiments were carried out in order to predict air quality consequences. Constraints in terms of budget and time did not permit wind-tunnel experiments to be executed for all variations in spatial distribution of pollutant sources in the study area. A limited number of experiments were therefore carried out and an interpolation method was designed to use the experimental results for the prediction of the impact from arbitrary sources and wind directions. Long term averaged concentrations were predicted by combining this method and data on long term distribution of windspeed and wind direction. A semi-empirical statistical method was used to predict the frequency of exceedance of air quality standards. Copyright (C) 1996 Elsevier Science Ltd