Smog Check has existed in various forms since the 1960s. Multiple studies have shown emissions increase due to lack of proper vehicle maintenance. Smog Check was designed to correct this; thus improving air quality.

Smog Check has been extensively evaluated numerous times. Key findings include:

• Emissions are being reduced, but by only one half as much as they could be;
• Current Smog Check stations are convenient, but cheating and fraud in testing and repair are too prevalent (up to 20% of tests in LA);
• A minority of vehicles are "gross emitters" which are responsible for the majority of correctable emissions, but many of these vehicles are not property tested or repaired;
• Emission benefits of Smog Check could be improved with better inspections and repairs, but testing must be done with dynamometers (treadmill-like devices), and the old repair cost limit and waiver provisions must be overhauled.

The 1990 federal Clean Air Act amendments require states to improve their current Smog Check programs. The Act includes general guidance as well as specific elements that states must include in their smog check laws. For example, the federal statute provides that consumer repair expenditures must be raised to at least $450.

The overall program structure, including the specific smog test procedure and hardware, was delegated to the U.S. EPA to define in regulations. The implementing regulations by U.S. EPA all but required 100% of the vehicles in the covered areas to be inspected at centralized test-only stations using expensive test equipment called the I/M 240.

California developed an alternative based on identifying likely gross emitting cars, inspecting them at special test-only centers, and verifying their proper repair. Up to 85% of vehicles continue to be inspected at current neighborhood garages.

U.S. EPA agreed to a pilot evaluation, which the California Legislature authorized. Results show the California approach has merit. An Independent Review Committee concurred. The Legislature authorized Smog Check II based on pilot evaluation and agreement by U.S. EPA to approve the State Implementation Plan (SIP).

Federal Highway Act directed U.S. EPA to allow alternative approaches to improving Smog Check, essentially endorsing the California approach. The Bureau of Automotive Repair (BAR) began implementing Smog Check II. Ongoing evaluation is required by U.S. EPA to ensure the program meets performance targets.

On September 26, 1996, U.S. EPA approved the SIP, which includes Smog Check II.

Webmaster - Tom Bryant, to make comments Click here   

Last Updated: 02/10/2006