California approves heavy-duty vehicle smog check program

As they often do, the California Air Resources Board (CARB) has rolled out a first in the nation air regulation for medium- and heavy-duty trucks and buses. Recently approved by CARB, is a ‘smog check’ regulation for vehicles with a gross vehicle weight rating (GVWR) greater than 14,000 pounds. CARB estimates approximately one million vehicles, operating in the state, will be affected by the new regulation. Once fully in place, the regulation is expected to reduce NOx and fine particle diesel pollution by as much as 82 tons per day.

Initially, the program includes emission control system inspections twice a year, with a phased-in increase to four inspections per year for trucks with on-board diagnostics. Like the existing passenger cars and light-duty truck smog check program, vehicle registration in the state will require passing the inspections. However, different from the smaller vehicle program, there is no requirement to go to a smog check station. Using onboard diagnostics (OBD), owners will be able to complete the required test and send the data without going to a testing location. Older heavy-duty vehicles without OBD will continue the current opacity testing requirements with an added visual testing component, twice each year.

Key to remember: CARB approves medium- and heavy-duty truck and bus smog check program starting in 2023.