Emissions Test Requirements

• OBD-equipped vehicles: 2 times per year, increasing to 4 times per year after 3 years.
• Non-OBD equipped vehicles: 2 times per year.
• Agricultural vehicles and California registered motorhomes: Once per year.

Benefits

• Keeps trucks operating at maximum efficiency, saving fuel and other costs.
• Streamlined testing with minimal downtime.
• Ensures trucks operate cleanly, improving air quality in communities where trucks are common.
• Ensures all trucks operating in California meet the same standards.
• Assures the ability to renew Department of Motor Vehicles (DMV) registration.

Requirements

Clean Truck Check requires all diesel and alternative fuel trucks and buses with a gross vehicle weight rating (GVWR) over 14,000 pounds, including out-of-state and out-of-country vehicles, California motorhomes and agricultural vehicles, to:

• be regularly tested to ensure all emissions-related equipment is functioning properly.
• report the testing data to CARB.
• pay a compliance fee of $30 per year per vehicle.

Notice to Submit Testing (NST)

Since January 2023, roadside emissions monitoring devices have been deployed throughout California to screen for high emitting vehicles. Owners of vehicles identified as potential high emitters will be issued a NST letter and have 30 days to submit a passing emissions test to CARB. Failure to do so will result in a violation, loss of compliance certification, and DMV registration hold.