The California Air Resources Board announced that its month-long multi-agency campaign to ensure that trucks traveling on California's roadways are obeying state air pollution laws was a huge success.

With assistance from the California Highway Patrol, Caltrans and the California Department of Food and Agriculture, CARB staff inspected 4,053 trucks at roughly 40 locations throughout the state during August, noting an overall compliance rate of more than 80%.

Trucks were inspected for compliance with many air pollution laws, including those requiring owners of certain model year vehicles to install diesel soot filters to reduce harmful diesel emissions.

In particular, for 1996-1999 model year trucks - the first model years required to currently be in compliance under the comprehensive Truck and Bus regulation passed in 2008 - the compliance rate was 90%.

This includes those truck owners who met the regulatory requirements by either registering their vehicles with CARB to take advantage of flexibility in the regulation or those who had already installed diesel soot filters.

"We're pleased to see such a high level of compliance," said CARB Executive Officer James Goldstene. "While ARB will continue to dedicate significant resources to assist fleets in complying with California's clean truck requirements, owners and operators should understand that our enforcement efforts will continue throughout the year, and that our goal is to make every month a 'clean truck month.'"

Overall, a total of 817 citations were given during the four-week effort. Of that total, 212 were for violations of the Transport Refrigeration Unit rule, 191 for non-compliance with the Bus and Truck rule, 187 for idling infractions, and 174 for Emissions Certification Labels violations.

To help educate drivers and reinforce the importance of obeying air pollution laws and proper vehicle maintenance, CARB staff distributed more than 4,600 information packets in English and Spanish.

Vehicle owners may want to take note of impending deadlines in order to place equipment orders and prepare for compliance with a variety of regulations.

Deadlines coming up quickly for diesel vehicles include:

Dec. 31

- Transport Refrigeration Units with 2005 model year engines must be replaced with Ultra-Low-Emission TRUs.

Jan. 1

- Under the Truck and Bus regulation, diesel truck fleets must either install diesel soot filters (or upgrade equipment) on trucks with 2000 to 2004 model year engines or meet phase-in option requirements.

- For vehicles covered under the Drayage Truck Regulation, 2005-2006 engine model year trucks greater than 33,000 pounds gross vehicle weight rating must have diesel soot filters.

Tractor-Trailer Greenhouse Gas regulation:

- Fleets with 20 or fewer affected trailers must register if they want to use a compliance option that will allow them up to four additional years to participate in the Small Fleet Compliance Plan.

- Low-rolling resistance tires are required for 2010 model year and older tractors that pull 53 foot-long box-type trailers.

- SmartWay aerodynamic requirements must be met by all 53-foot or longer box-type trailers not using a phase-in option.

For specific information on CARB's rules and deadlines, visit the CARB Truck Stop or call the Diesel Hotline at 1 866 6DIESEL (1-866-634-3735).