California Air Resources Board

SACRAMENTO - The Air Resources Board today hailed NHTSA and U.S. EPA's announcement of the development of a next phase of greenhouse gas (GHG) standards for heavy duty vehicles. The federal agencies have announced they will begin their rulemaking process on regulations, known as the Phase 2 standards, which require further reductions in GHG emissions and corresponding higher efficiency standards from vehicles ranging from heavy pick-up trucks to tractor-trailers weighing more than 33,000 pounds.

“We look forward to teaming with the federal agencies and strongly support this effort. We are excited to share the California experience and technical expertise gained from our early actions to reduce emissions and save fuel from the heaviest trucks via our California tractor-trailer greenhouse gas program over the last six years,” said Air Resources Board Chairman Mary D. Nichols. “The Phase 1 standards that are already in place will reduce these emissions by about 10 percent, and we look forward to developing more ambitious Phase 2 regulations to provide even greater benefits.”

California assumed a leadership role in regulating GHG emissions with passage of The Global Warming Solutions Act (AB 32) in 2006. In 2011, the federal Phase 1 greenhouse gas standards for heavy duty vehicles were approved nationally. As part of its climate and air quality improvement programs, California aligned its heavy duty vehicle requirements with those regulations in 2013.

And now, ARB is working with the U.S. EPA and the U.S. Department of Transportation's National Highway Traffic Safety Administration (NHTSA) on national GHG standards and corresponding fuel efficiency standards for medium- and heavy-duty vehicles. The collaborative work with U.S. EPA and NHTSA will build on the ARB's experience with reducing emissions from diesel trucks and buses which have already reduced black carbon, a powerful greenhouse contaminant, by 90 percent in the state.

The federal Phase 1 standards required more efficient engines, use of low rolling resistance tires, reduced idling and aerodynamic improvements. The Phase 2 standards are expected to prompt even more innovation, improvements and significant fuel savings for the end-user.