Measuring Mass Emissions of Diesel Particulate Matter by the DMA-APM Method(Second Report)

-Comparison with the Gravimetric Filter Method-

Abstract

For measurement of very low diesel exhaust PM emissions, the filter gravimetric method may no longer be sufficiently accurate due to evaporation of filtered particles from or adsorption of condensable gases onto the filter media. For more accurate determination of the low emissions, we have been developing a technique based on the DMA (Differential Mobility Analyzer) and APM (Aerosol Particle Mass Analyzer) method. The results of somparison measurement between DMA-APM (online) method and filter gravimetric method show that the mass concentration by filter gravimetric method indicates lower value about 15% compared with online mothod.