Monitoring of Air Pollution due to Vehicles at Ratmalana, Sri Lanka

Abstract

Urbanization and industrialization are the main causes of air pollution in most of the areas in Sri Lanka. Air pollution is occurred due to natural and manmade activities. Monitoring of air quality especially in urban areas in Sri Lanka is significant because the quality of air is degraded day by day due to various activities. In Sri Lanka, most activities on air quality monitoring and management are concentrated in Colombo, which is the commercial capital of Sri Lanka. However, few attempts were taken to study air pollution in other industrial areas as well. The transportation sector is responsible for the majority share of the most of the gaseous emissions to the environment with compared to any other sector. Therefore, this attempt has been made to discuss the air pollution due to transportation sector at Ratmalana area in Sri Lanka. Sri Lanka has adopted emission standards for all vehicles, but those standards are yet to be effectively enforced. Further, there is no mechanism to evaluate the benefits due to emission control strategies as no reliable emission inventory is available, especially to estimate local concentration levels. Therefore, the main objectives of this paper are to discuss the level of air quality in this particular area and to develop a vehicle emission inventory that could be used for estimating vehicle emission with respect to the special distribution. A traffic survey was conducted near Galle road at Ratmalana for about two weeks. The emission standards were collected from Automated Air Quality Monitoring station which is operated by the Central Environmental Authority of Sri Lanka. The level of emission and values of emission of each pollutant were estimated for each vehicle. It was found that the major sources of Carbon Dioxide, Nitrogen Dioxide, Sulfur Dioxide and Particulate Matter are Light Trucks and Heavy Duty Vehicles, however; the major sources of Carbon Monoxide are Cars and Vans. In addition, it was estimated the paths of air pollution and percentages of each vehicle of each pollutant per hour. Finally, it was recommended to use the Carpooling system and public vehicles to mitigate the air pollution due to vehicles at Ratmalana, Sri Lanka.