Non-exhaust PM emission measurements of a light duty vehicle with a mobile trailer

A trailer-based mobile measurement approach for analyzing non-exhaust emissions of a light duty vehicle is presented. Based on a tracer gas experiment which allowed a mapping of the particle dispersion within the wake of the vehicle, emission factors were estimated. A combination of the results from tracer gas experiment, wind tunnel tests and local airflow measurements was taken into account to characterize the vehicle wake and optimize the position of the measurement devices in the wake of the vehicle. Diffuser type inlet devices were employed to correct for anisokinetic sampling. Measurements on unpaved and dust loaded agricultural paved roads as well as more than 800 km of real world driving were conducted with estimated PM10 emission factors varying over several orders of magnitude (10–42,000 mg vehicle−1 km−1 (mg vkm−1)). Emission factors were found to increase with increasing vehicle velocity. The lowest emission factors were measured on motorways. The coefficient of variation for the measurements varied from 10% to 30%.