A simulation model for predicting air quality along urban main roads is being studied. The previous reports dealt with the development of atmospheric diffusion model and a photochemical reaction model as well as traffic flow model. The present report describes the incorporation of the atmospheric diffusion model and the traffic flow model, which enables simulation of the effect of traffic parameters on air quality along the main roads. Emission mass from each vehicle is calculated by the traffic flow model using instanteneous velocity and accelaration of the vechiles. Then, the emission data is converted into increase of concentration, and passed into the atmospheric diffusion model for its source term. A case study was conducted using the incorporated model, in which some traffic parameters were studied to show their infulence on traffic flow and air qulity around the road.
