Internal combustion engines used in most of today's vehicles are a significant source of man-made air pollution. These engines produce four types of emissions that can be regulated through emissions inspection and maintenance (I/M) programs:
- hydrocarbons
- carbon monoxide
- oxides and nitrogen
- particulates
In the United States, the 1990 Clean Air Act gives the Environmental Protection Agency (EPA) broad authority to regulate motor vehicle emissions. Vehicles built for sale in the United States must meet tailpipe and evaporate emissions standards, as determined by Congress. The EPA generally sets performance standards, rather than the pollution control devices to be used.
Implementation of I/M programs is mandatory in the United States in those areas that are not in compliance with the National Ambient Air Quality Standards (NAAQS), under provisions of the 1977 Clean Air Act.
In Canada, the Canadian Council of Ministers of the Environment (CCME), serves as an intergovernmental forum for discussion and joint action on environmental issues, and it makes recommendations about where I/M programs should be implemented. The CCME also publishes federal guidelines for I/M programs that provide a standard format for the future development of I/M programs in Canada.
AAMVA's Involvement
Vehicle emissions testing programs are an integral part of AAMVA’s Vehicle Safety and Inspection Committee activities. The committee has been working on assisting jurisdictions with emissions testing programs and standards for the past few years.
In addition, AAMVA’s Vehicle Safety and Inspection Handbook provides information on emissions Inspection and Maintenance (I/M) programs, with an overview of the emissions test strategies followed within the U.S. and Canada.
Related Information
Looking Beyond: The Future of Cleaner Vehicles
John Cabaniss
Vehicle Emissions Equipment in 2010
Mark Hall
OBD II in New York State
Donald Savage