Air Pollution in Elevated Walkway Microenvironments in Urban Street Canyons

Hong Kong is dominated by busy and often polluted urban environments. Here hightraffic flows have led to the construction of many walkways, which can in places developinto complex networks. Obviously such structures mean that pedestrian flow is safelysegregated from the roadway, but there are also views that this lowers the roadsideexposure to air pollutants. Air pollution exerts an important control on the health effectsin urban populations and is a particular problem for the Pearl River Delta. It is thoughtto be responsible for the rapid increase in the number of people suffering from non-communicablediseases presents one of the biggest challenges to the health care systemsin Hong Kong with its aging population. We proposed research will examine the potentialexposure of people in the roadside environment and monitor the concentrations ofcarbon monoxide and fine particles at sufficient detail to map the concentrations in thewalkways and their surroundings. The transfer of pollutants into the walkways will alsobe modelled by computational fluid dynamics and give an indication of features thataffect transfer of air pollutants to their interiors. The project should help develop policyas part of Hong Kong desire to be a walkable city, but also offer guidance to the designand positioning of new walkways