SACRAMENTO – June marks the one-year anniversary of the California Air Resources Board's new heavy duty diesel vehicle inspection program (https://ww3.arb.ca.gov/enf/hdvip/hdvip.htm).

        With more than 21,500 trucks and buses inspected, the failure rate has been 8.5 percent with 1,831 violations issued.  To date, more than 1,100 trucks and buses have been repaired under the program, resulting in less diesel smoke polluting California's skies.

        Michael P. Kenny, ARB Executive Officer said, "Our Heavy Duty Vehicle Inspection Program is one of our most effective tools for control of smoking diesel vehicles.  While diesel vehicles make up only about 3 percent of California's motor vehicle fleet, they contribute nearly 60 percent of all motor vehicle particulate and 30 percent of all motor vehicle NOx, the major component of ozone."

        The trucking industry seems accepting of the program as evidenced by the low rate of citation appeals (2.8 percent) compared  to a 15 percent rate of appeals when a similar program was run by ARB from 1991 through 1993.

        The program is run by ARB inspectors who use a beam of light to measure the darkness or opacity of smoke coming from a truck or bus exhaust pipe.  Pre-1991 engines fail if the smoke opacity is 55 percent or above while 1991 or newer engines fail with an opacity of 40 percent or above.  Fix-it tickets are issued for pre-1991 vehicles if smoke opacity is 55-69 percent.

        Penalty for a first citation is $800 of which $500 is waived if the engine is repaired within 45 days.  A second citation within one year brings with it an $1800 penalty. Most penalty funds are deposited into the Diesel Emission Reduction Fund to fund clean diesel technology research and incentive programs.