Central Carolina Vehicle Particulate Emissions Study

In-use, light-duty vehicles were recruited in Cary, North Carolina for emissions testing on a transportable dynamometer in 1999. Two hundred forty-eight vehicles were tested in as received condition using the IM240 driving cycle. The study was conducted in two phases, a summer and winter phase, with half of the vehicles recruited during each phase. Regulated emissions, PM₁₀, carbonaceous PM, aldehydes and ketones were measured for every test. PM_2.5, individual volatile hydrocarbons, polycyclic aromatic hydrocarbons, sterane and hopane emissions were measured from a subset of the vehicles. Average light-duty gasoline PM₁₀ emission rates increased from 6.5 mg/mi for 1993-97 vehicles to 53.8 mg/mi for the pre-1985 vehicles. The recruited fleet average, hot-stabilized IM240 PM₁₀ emission rate for gasoline vehicles was 19.0 mg/mi.