The goal of this study was to provide a method of estimating the concentration of any vehicle generated pollutant in areas where people are in close proximity to vehicles (microscale exposure situations). A list of common exposure situations was extracted from several hypothetical daily activity routines. These situations were: residential garages, parking garages, tunnels, street canyons and expressways. For each of the situations an appropriate dispersion model was selected from the literature for use in obtaining pollutant concentrations. To determine the exposure level for each case, the pollutant concentrations were calculated for typical and severe actual situations. The range of physical variables for each type of situation was obtained from a search of the literature, to define the typical and severe cases for each situation. Using the physical variables describing the typical and severe cases, actual locations were chosen to represent the typical and severe exposure for each situation. Pollutant concentrations were calculated for these actual locations using the chosen dispersion models. Concentrations were calculated using one gram per mile for tunnel, street canyon, and expressway situations, and one gram per minute for residential and parking garages. To use the calculated concentrations with emission factors other than one gram per mile or one gram per minute, the concentrations given in the report are multiplied by the desired emission factor in the correct units.