California ARB adopts emission rules for in-use diesel trucks

15 December 2008

The California Air Resources Board (ARB) finalized the proposed emission regulations for heavy-duty diesel trucks that operate in California. The Statewide Truck and Bus rule introduces the following requirements:

• Beginning January 1, 2011, truck owners must install diesel particulate filters on their rigs, with nearly all vehicles upgraded by 2014.
• Truck owners must replace engines older than the 2010 model year according to a staggered implementation schedule that extends from 2012 to 2022.

Another adopted rule, the Heavy Duty Vehicle Greenhouse Gas Emission Reduction measure, requires long-haul truckers to install fuel efficient tires and aerodynamic devices on their trailers that lower greenhouse gas emissions and improve fuel economy.

Heavy-duty trucks—responsible for 32% of NOx emissions and nearly 40% of PM emissions from diesel mobile sources—are the largest source of diesel emissions still not regulated under the California Diesel Risk Reduction Plan. The greenhouse gas reduction measure applies to more than 500,000 trailers, while the diesel regulation applies to about 400,000 heavy duty vehicles that are registered in the state, and about 500,000 out-of-state vehicles that do business in California. However, because many heavy duty vehicles are replaced or retired due to normal business practices on a faster schedule than what the new regulation will require, the number of vehicles expected to be retrofitted by 2014 under the rule is about 230,000, while up to 350,000 vehicles would be replaced earlier than normal over the next 15 years, estimates the ARB.

To provide flexibility, the diesel regulation is structured so that owners can choose from among three compliance options to meet regulation requirements. There are exceptions to the regulation, including low-use vehicles, emergency and military vehicles, and personal use motor homes. School buses would be subject only to requirements for reducing diesel particulate matter and not for engine replacement.

To help truck owners upgrade their vehicles, the state is offering more than a billion dollars in funding opportunities. Options include Carl Moyer grants, Proposition 1B funds, and AB 118, which establishes a low-cost truck loan program to help pay for early compliance with the truck rule. The ARB is also evaluating ways to integrate these programs so that truckers can get a grant and a loan at the same time.

To reduce diesel emissions and improve air quality and public health, the ARB adopted a Diesel Risk Reduction Plan in 2000. The regulations already passed under the Plan cover urban buses, garbage trucks, school bus and truck idling, stationary engines, transport refrigeration units, cargo handling equipment at ports and rail yards, off-road vehicles, port trucks and other sources.

Source: California ARB