Abstrakt
This work investigates the spatial distribution of particulate matter in Spořilov, a Prague residential neighborhood completely surrounded by three freeways, two of which are major heavy truck thoroughfares. Internal combustion engines are often the prime source of air pollution.
The emissions of PM are not distributed uniformly; a small fraction of high emitting vehicles account for a large share of fleet PM, and for a given vehicle, PM emissions tend to be concentrated into short high-emissions episodes (e.g. accelerations, hard transitions or high load following a period of extended idling). Size-resolved (5-500 nm) measurements of particles were taken with an online particle classifier (EEPS, TSI) mounted, along with batteries, GPS and other accessories, on a hand cart and pushed around the neighborhood on five separate days, making one-minute or longer stops at places of interest.
Meteorological data from a nearby observatory and ambient air quality data from the national monitoring network were used. The average concentrations of particles ranged from under or around 104 #/cm3 on quiet residential streets to 2-8 x 104 #/cm3 on streets next or close to a freeway to 1-2 x 105 #/cm3 on walkways over and near the freeway, with peak concentrations over 106 #/cm3.
Low concentrations of nanoparticles in the inner neighborhood and general absence of a significant accumulation mode throughout the area suggest that woodstoves or other stationary sources were not likely a major contribution to the concentrations. The measured concentrations near the freeways were much higher than elsewhere in Prague