Vehicle Emission I/M Programs

Since the enactment of the Clean Air Act Amendments of 1990, a wide array of motor vehicle emission inspection programs have been developed across the nation. While some states are required to implement these programs, many have adopted these programs as a cost-efficient and effective way to improve air quality.

Although proven to reduce emissions, these important programs are not without their critics.

The Automotive Service Association has compliled this study of motor vehicle emissions inspection and maintenance programs to show the wide variety of approaches that exist. The last comprehensive study was completed April 1999. Every state was contacted and asked to complete a detailed survey about their local programs. Many of these programs are extremely complex, and we have tried to present them simply and consisely.

Click here to download a PDF copy of the report.