Vehicular emissions and air quality on the roads

In order to maintain/improve Singapore’s air quality, this project endeavours to assess the impact of vehicle emissions on the air quality. This research was carried out in four separate phases to achieve this objective. The first phase involved extensive literature review to understand the background of Singapore’s air quality and its relationship to vehicular emission. In the second phase, an experimental design was utilised to determine experiment setup and methodology used to collect and evaluate the air samples collected. The third phase was conducted between October 2010 and January 2011 to collect field data. Data processing and analysis was carried out in the final phase to explain the findings of the experiment. The findings indicate that; • The main pollutant of concern identified on the expressway and arterial road is particulate matter (PM). • The PM peak and trough concentration were affected by traffic counts measured at each point of time. • Diesel vehicles are the main source of PM emission, in which Euro II Heavy Weight Vehicles and Euro II Light Weight Vehicles are two highest PM emitters on the expressway and arterial road. • More than 50% and 30% of PM2.5 monitored in the ambient environment came from diesel vehicles on a weekday and weekend respectively. Although the diesel vehicle population has been increasing each year, Singapore’s PM concentration has been kept fairly constant between 2004 and 2009. This suggests that the emission control for vehicle emission may have been a major factor that has helped to control diesel vehicle emissions. The significance of vehicular exhaust emission standards to control diesel vehicle emission is elaborated. Future studies that could be carried out to further strengthen the link between the PM emission and vehicular exhaust emission standards are recommended.Bachelor of Engineering (Environmental Engineering