AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Effects of Truck Retrofit/Replacement Program on Diesel Engine Emissions at the Port of Oakland
CHELSEA PREBLE, Timothy Dallmann, Steven DeMartini, Nathan Kreisberg, Susanne Hering, Robert Harley, Thomas Kirchstetter, University of California, Berkeley
Abstract Number: 548 Working Group: Urban Aerosols
Abstract To reduce pollutant emissions from trucks around ports and rail yards, the California Air Resources Board’s Drayage Truck Regulation required replacement of trucks with pre-1994 engines and retrofit with diesel particulate filters (DPFs) of trucks with newer engines. We measured pollutants in the exhaust plumes of individual heavy-duty trucks at high time resolution (1-2 Hz) as they drove by a mobile lab that was parked on a bridge above the traffic en route to the Port of Oakland. This study adds to prior fieldwork at the Port that demonstrated 50 and 40% reductions in fleet-average emissions of black carbon and nitrogen oxides (NOx), respectively, resulting from the first phase of the emission control rule. Emissions of ultrafine particles (number and size distribution), black carbon, and nitrogen dioxide (NO2), in addition to the NO2/NOx emission ratio, were measured in this study and linked on a truck-by-truck basis to detailed information about each engine and installed emission control equipment. This analysis examines the distribution of pollutant emissions across all Port trucks, and among various subpopulations (e.g., specific engine years, types of emission controls). The current age distribution indicates that the majority of trucks are now equipped with DPFs. A fraction of trucks have DPFs that are several years old, and a significant portion of the Port truck fleet is now also equipped with selective catalytic reduction systems. The results of this study are significant as a similar regulation targeting emissions from all on-road trucks and buses in California is being implemented, and other states are likely to follow California’s lead.