title: Spatial applicability of emission factors for modeling mobile emissions.
abstract: Driving cycles are used to create mobile emission factors. Emission factors are, in turn, used to estimate mobile source inventories, provide standards for new vehicle emissions testing, and facilitate comparisons of laboratory experiments. This study examines the spatial representativeness of the driving cycles underlying California's CO, THC, and NOx emission rates that are applied when estimating regional mobile emissions inventories. Sixteen randomly selected vehicles were tested on a laboratory dynamometer using driving cycles representative of driving in different cities. A total of 214 tests, with repetitions, representing six driving cycles, were conducted on the 16 vehicles. We used a random effects analysis of variance to statistically examine the differences in the resulting emission rates. The study results suggest that California mobile source pollutant inventories prepared using emission rates based on the standard drive cycle may be off by as much as 30% for regions where traffic congestion and roadway networks differ significantly from those of Los Angeles.
authors.affiliation: Department of Civil and Environmental Engineering, University of California, Davis 95616, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Niemeier
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001334:Automobile Driving; D002140:California; D002947:Cities; D008962:Models, Theoretical; D012016:Reference Values; D015203:Reproducibility of Results; D001335:Vehicle Emissions
chemical_list: D000393:Air Pollutants; D001335:Vehicle Emissions