An historical overview of the U.S. experience with controlling emissions from highway motor vehicles is presented. The evolution of new motor vehicle emissions certification practice, end-of-assembly-line inspection, in-use surveillance and recall, inspection and maintenance, and antitampering programs are discussed. The changes in motor vehicle designs and fuel formulations resulting from these practices are also described, along with associated changes in the characteristics of emissions. Future possible directions for further improvements are described as the U.S. Congress considers changes to the Clean Air Act requiring increasingly stringent new motor vehicle emission standards, changes in procedures for identification and repair of motor vehicles that have been tampered with or poorly maintained, and requirements for use of cleaner, more environmentally benign alternatives to conventional petroleum-based fuels.

"PB91-136911." Includes bibliographical references (p. 29-31).