Certified Diesel Opacity Testing – Northern California

  • Periodic Smoke Inspection Program (PSIP) Testing

    Operating a fleet of diesel vehicles in California? Complying with the California Air Resources Board (CARB) is the law. Getting and staying compliant with PSIP testing can be made easy with one simple phone call. Commercial Power Sweep, Inc. (CPSI) has mobile on-site testing and is a CCDET certified Company.


    We have competitive pricing and are available to come to your location. Get on our annual PSIP/Opacity testing program now and worry no more!

    Call us at (707) 255-1769

  • Facts about the Periodic Smoke Inspection Program (PSIP)

    In 1990 CARB’s Periodic Smoke Inspection Program (PSIP) became law. The program is meant to reduce excessive smoke emissions from heavy-duty diesel trucks and buses.

    • Vehicles affected: Any diesel vehicle that is operated in California, part of a fleet of two or more vehicles and greater than 6,000 pounds GVWR with an engine more than four years old.
    • What’s required by you: Each affected vehicle must have and pass an annual smoke opacity test performed according to the SAE J1667 test procedure. Any vehicle that does not pass must be promptly repaired, brought up to compliance and re-tested.
    • Standards that must be met: 55% opacity for pre-1991 engines and 40% for 1991 and newer engines.
    • What’s being tested: The color (opacity) and amount of smoke in the vehicle’s exhaust.
    • Other names for the test: Opacity Test, Smoke Opacity Test, Smoke Test, Diesel “Snap” Test, Diesel Smoke Check Test, Diesel Snap Throttle Test, Diesel Smog Test, Ringleman Test, etc.
    • Records that you must keep: Minimum past 2 years current consecutive records of opacity test, all opacity repair information and post-repair opacity test for each vehicle.
    • Penalties for non-compliance: A fleet owner that neglects to perform the annual smoke opacity inspection on applicable vehicle may be subject to a penalty of $500.00 per vehicle per year.

    To review full details and the most current information for the Periodic Smoke Inspection Program (PSIP) from CARB, please go to:


    Call us at (707) 255-1769

    or fill out our form to request an appointment.