Automotive Sulfate Emissions-A Baseline Study

A baseline testing program was designed and implemented by EPA wherein 78 vehicles were tested in 5 laboratories. The objectives of this study were to 1) obtain sulfate emission factors on a wide variety of different in-use vehicles using current and advanced emission control methods, and 2) determine the effect on sulfate emissions of vehicles meeting increasingly stringent gaseous emissions standards. The program was designed such that the vehicles were divided into the following classes: 1) production non-catalyst vehicles, 2) production catalyst vehicles - grouped according to emissions standards, 3) advanced non-catalyst vehicles, 4) advanced catalyst vehicles, and 5) fleet vehicles.