[Abstract]

Reduction of the particulate matter (PM) emitted by diesel vehicles is an urgent task. Reflecting smoke meters are currently the main PM evaluation method employed within Japan. This method however suffers from the drawbacks of having inadequate sensitivity for blue and white smoke and not
permitting continuous measurement. Horiba has now developed as a commercial product the MEXA-130S Opacimeter, which is able to measure continuously and with high sensitivity all of the components of smoke, including blue and white fumes as well as black. This paper describes the measuring principles and features of the MEXA-130S and presents the results of performance tests conducted on it. Additionally, the MEXA-130S was used with an engine run on a chassis dynamometer to examine the correlation with PM measuring methods. Further, a diesel vehicle equipped with an MEXA-130S was driven through actual urban areas to examine the possibility of onboard
measurement of exhaust gas.