Light-Duty Motor Vehicle Exhaust Particulate Matter Measurement in the Denver, Colorado, Area

Area of Science:

• Environmental Science
• Atmospheric Chemistry
• Transportation Emissions

Background:

• Particulate matter (PM) emissions from vehicles are a significant air quality concern.
• Understanding real-world emissions is crucial for accurate air quality modeling.
• Previous studies may not fully represent current vehicle fleets and driving conditions.

Purpose of the Study:

• To quantify particulate matter (PM) emissions from in-use, light-duty vehicles in the Denver, CO region.
• To collect data for updating emissions inventories used by air quality management programs.
• To assess differences in emissions between summer and winter testing conditions.

Main Methods:

• Vehicles were tested on chassis dynamometers using the Urban Dynamometer Driving Schedule (UDDS) and IM240 driving schedules.
• Particulate matter (PM10) and regulated emissions were measured.
• Particle size distributions and continuous particle number emissions were analyzed.
• Testing included gasoline and diesel vehicles, with a focus on those emitting visible smoke.

Main Results:

• Data on PM and regulated emissions were collected for a diverse fleet of light-duty vehicles.
• Seasonal variations in emissions were investigated through summer and winter testing.
• Particle size distributions provided insights into the physical characteristics of emitted particles.
• Continuous particle number data offered a more detailed assessment of emission characteristics.

Conclusions:

• The collected data provides valuable information for refining emissions inventories.
• Findings support improved air quality modeling and regulatory strategies in the Denver region.
• This study contributes to a better understanding of vehicle-related air pollution.