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About the Vehicle Inspection Program


When Oregon began implementing requirements of the federal Clean Air Act, in the 1970's and 1980's, air quality in the Portland and Medford areas of the state did not meet federal standards for ozone and carbon monoxide. In response to the poor air quality, the Department of Environmental Quality was required to develop plans to reduce these pollutants, and to maintain compliance with air quality standards.

Some of the same air quality challenges persist today. For example, concentrations of ground-level ozone are on the rise. Both the Portland and Medford-metro areas have experienced unhealthy levels of ozone in recent years. Emissions from cars and trucks are responsible for the majority of the pollution that produces this ozone. Cars and trucks are also the source of other federally regulated Criteria and Toxic pollutants.

To address the leading cause of pollution, Oregon operates a biennial vehicle emissions testing program in the Portland and Medford areas. Vehicles registered within the two testing boundaries must pass an emissions test in order to be re-registered with the Oregon Department of Transportation, Driver and Motor Vehicle Services. 

The Oregon Vehicle Inspection Program carries out its emission testing program through seven Clean Air Stations, 6 in Portland and one in Medford. The program also tests vehicles through one of approximately 200 private sector DEQ Too service providers.

All of this testing work is administered from the program Technical Center, where the program teams perform a wide range of administrative functions. The functions include facility maintenance, information technology, contract and procurement, accounting and budget, business operations and other functions. Also, and more recently, the program's activities expanded to include the implementation of the registration and retrofit requirements of HB 2007, applicable to large diesel trucks.