Roadside measurement and prediction of CO and PM_2.5 dispersion from on-road vehicles in Hong Kong

This study investigates the traffic induced gaseous and particle emissions dispersion characteristics from the typical urban roadside sites in Hong Kong. Concentrations of carbon monoxide, CO, fine particles, PM_2.5 pollutants, and the traffic and ambient atmospheric conditions at three selected local urban road sites were simultaneously measured. A developed local general finite line source model (GFLSM) was used to predict the local roadside CO and fine particle concentrations. A high level of agreement found between the measured and calculated CO and PM_2.5 data. Generally, the roadside concentrations of gaseous and PM_2.5 pollutants decrease with the distance away from the road and the exposure to both gaseous and particle pollutants in the vicinity of the selected urban road sites is interrelated to on-road vehicle emissions. It has also demonstrated that the developed local general finite line source model has the capability of reasonably predicting the characteristics of gaseous and particle pollutant dispersion from on-road vehicles for the local urban air quality.