On-road Measurement of Diesel Particulate Matter from In-Service Vehicles

Very little data is currently available that quantifies actual amounts of Diesel Particulate Matter being emitted by in-service vehicles. A prototype on-board measurement system capable of quantifying real world particulate emissions is under development, with a view to establishing the capabilities and limitations of the simplified, low-cost approach chosen. The system operates by continuously drawing off and filtering a constant fraction of the exhaust gases, and storing the collected particulate matter for eventual weighing. The system was tested under urban and motorway driving conditions and some initial results are presented here. Whilst many limitations are evident, the approach has the potential to give approximate aggregate values of particulate matter emitted from vehicles over single or multiple journeys, under real world operating conditions.