Abstract for presentation at 14th IUAPPA World Congress

This paper evaluated the effectiveness of on-road mobile source air pollution control programs in Taiwan during last ten years. Vehicle kilometer traveled and registration numbers were growth 60-70% during pass decade since 1995. Taiwan Environmental Protection Agency has tried to develop a comprehensive strategy based on incentive and command-control approach to reduce emission from on-road mobile sources. There are several programs have been conducted, include adoption of new exhaust emission standards, inspection and maintenance program, clean fuel program, high-polluted vehicle retirement program and transportation management. The results showed that enhanced exhaust emission standard for new vehicles was effective to promote new vehicle cleanness. Inspection and maintenance (I/M) program for motorcycle and diesel engine has showed the significant abatement of air pollutant emissions. The clean fuel program were focused on reduce sulfur content in fuel. Current diesel sulfur concentration has been regulated to less than 50 ppmw, and gasoline sulfur concentration will has same level in 2007. Incentive program for high-polluted vehicle retirement and purchase of cleaner vehicle have shown the slight abatement of air pollutant emissions. In overall, motorcycle control measures present significant abatement of NMHC and CO emission, the variations were 54% and 25%, respectively. The emission reductions were 74% (CO), 44% (NMHC) and 42% (NO_x), respectively, by implemented gasoline vehicle control measures. Diesel engine measures were effective on particular matter. The mobile source control measures have showed an evident progress, but more effective measures for in-use vehicles should be proposed for further emission reduction in Taiwan.