Smog inspections ordered twice a year for California big trucks

December 13, 2021

Land Line Staff


Heavy-duty trucks and buses operating in California will now be subject to twice-a-year smog inspections.

The California Air Resources Board has approved a “smog check” regulation for medium- and heavy-duty trucks and buses to ensure that the emissions control systems remain efficient as the vehicle ages.

According to CARB, while heavy-duty vehicles with a gross vehicle weight rating greater than 14,000 pounds comprise only 3% of all vehicles on California roads, they are responsible for more than 50% of nitrogen oxides and fine particle diesel pollution from all mobile sources in the state.

Eventually, trucks with onboard diagnostics will be subjected to smog inspections four-times a year, according to a CARB news release.

The Board also directed a four-times per year testing frequency for trucks with on-board diagnostics to be phased in over time.

CARB was directed to develop and implement a comprehensive heavy-duty vehicle smog inspection and maintenance program by SB210. That bill was sponsored by Sen. Connie Leyva in 2019. Leyva is an ex-officio member of CARB.

“Just as passenger vehicles have already been doing for decades, it is long overdue that big diesel trucks undergo smog check testing so that we can continue to clean our air and improve public health across California,” Levya said in the news release.

As with passenger cars and light-duty trucks, California registration of these heavier vehicles will require passing the inspection. Unlike light-duty smog checks, however, there is no requirement to go to a brick and mortar heavy-duty smog check station.

Instead, heavy-duty vehicle owners will be able to complete the required test and deliver the information remotely without having to stop at designated testing locations.

For telematics users with an onboard diagnostics inspection that draws emissions control performance data from the vehicle’s internal computer, an inspection can be completed automatically without taking the vehicle out of operation.

Onboard diagnostics systems have been required by CARB on heavy-duty vehicles since 2013.

Older heavy-duty vehicles without onboard diagnostic systems would continue the current opacity testing requirements, with an added visual testing component, twice each year.

Officials plan to continue to augment the new testing requirements with inspections and testing randomly carried out at border crossings, California Highway Patrol weigh stations, fleet facilities and randomly selected roadside locations.

For more information, click here. LL

More news about California is available.