Techniques for Repeatable Measurement of PM Emissions from Light Duty Gasoline Vehicles

Concern over exhaust fine particles (sub-2.5μm) emissions from the transport sector due to their adverse health effects, has spread to include those from gasoline powered vehicles which are believed to dominate the fine particle size spectrum in urban centres.

The measurement of fine particle emissions from gasoline light duty engines poses many technical challenges 12. This paper discusses the methodology, testing and analysis protocols developed to allow the accurate quantification of PM from light duty gasoline vehicles. The developed methodology was used as part of an Australian Government funded study into the assessment of the health impacts of ethanol blend fuels 3.

The main technical challenges addressed were 1) the measurement of fine particle emissions and their size distribution from comparatively low emitting vehicles; 2) the alignment of particle sampling to the drive cycle phase in which they were produced, for example, allowing insight into cold start versus running levels; and 3) establishing statistical confidence in the subtle differences in PM emissions between fuel types.