This paper presents a method to estimate emission factors of motorcycles based on the local driving cycle and modal emissions measured in the laboratory. This method was developed to reflect real-world motorcycle traffic conditions of Hanoi, Vietnam as well as to correspond to the economical - technical infrastructure of Vietnam. | TẠP CHÍ KHOA HỌC VÀ CÔNG NGHỆ Tập 48, số 3, 2010 Tr. 101-110 PRELIMINARY ESTIMATION OF EMISSION FACTORS FOR MOTORCYCLES IN REAL-WORLD TRAFFIC CONDITIONS OF HANOI TA HUONG THU, LE ANH TUAN AND NGHIEM TRUNG DUNG ABSTRACT This paper presents a method to estimate emission factors of motorcycles based on the local driving cycle and modal emissions measured in the laboratory. This method was developed to reflect real-world motorcycle traffic conditions of Hanoi, Vietnam as well as to correspond to the economical - technical infrastructure of Vietnam. Applying into the estimation of emission factors of four selected air pollutants of motorcycles including HC (hydrocarbons), CO (carbon monoxide), CO2 (carbon dioxide) and NOx (as NO), the following results were obtained: (g/km), (g/km), (g/km) and (g/km), respectively. These emission factors are a significant contribution to Vietnam database of emission factors that are still scarce. Emission factors obtained in this study would also help improve the accuracy of emission models and emission inventories, which plays an important role in air quality management and traffic planning of Hanoi, Vietnam. 1. INTRODUCTION According to National State of Environment 2007, the transport sector is estimated to emit around 85% CO and 95% VOCs into the air of urban areas. Hanoi, with millions motorcycles (until June 2007), is now facing with serious air pollution problem [1]. Estimating emission factors of vehicles to calculate total emissions and to serve emission inventories, has great significance for air quality management. In developed countries, by fully worked-out data system of traffic conditions as well as vehicular types, not only emission factors database, but also statistics about vehicles, has been developed completely through main methods such as: totaling up the numbers of vehicles and experimenting with specific types of vehicles on test beds following given driving cycles; building .
