Clean Car Standards - Pavley, Assembly Bill 1493

This page last reviewed January 11, 2017


On September 24, 2009, the ARB adopted amendments to the “Pavley” regulations that reduce greenhouse gas (GHG) emissions in new passenger vehicles from 2009 through 2016. These amendments are part of California’s commitment toward a nation-wide program to reduce new passenger vehicle GHGs from 2012 through 2016.  ARB’s September amendments will cement California’s enforcement of the Pavley rule starting in 2009 while providing vehicle manufacturers with new compliance flexibility.  The amendments will also prepare California to harmonize its rules with the federal rules for passenger vehicles.

The U.S. EPA granted California the authority to implement GHG emission reduction standards for new passenger cars, pickup trucks and sport utility vehicles On June 30, 2009.

The first California request to implement GHG standards for passenger vehicles, known as a waiver request, was made in December 2005 and was denied by the U.S. EPA in March 2008.  That decision was based on a finding that California’s request to reduce GHG emissions from passenger vehicles did not meet the Clean Air Act requirement of showing that the waiver was needed to meet “compelling and extraordinary conditions.”

The ARB’s Board originally approved regulations to reduce GHGs from passenger vehicles in September 2004, with the regulations to take effect in 2009. These regulations were authorized by the 2002 legislation Assembly Bill 1493 (Pavley).

The regulations had been threatened by automaker lawsuits and were stalled by the U.S. EPA’s delay in reviewing and then initially denying California’s waiver request. The parties involved entered a May 19, 2009 agreement to resolve these issues.  With the granting of the waiver on June 30, 2009, it is expected that the Pavley regulations will reduce GHG emissions from California passenger vehicles by about 22 percent in 2012 and about 30 percent in 2016, all while improving fuel efficiency and reducing motorists’ costs.

ARB has adopted a new approach to passenger vehicles – cars and light trucks – by combining the control of smog-causing pollutants and greenhouse gas emissions into a single coordinated package of standards.  The new approach also includes efforts to support and accelerate the numbers of plug-in hybrids and zero-emission vehicles in California.  Find out more on the Advanced Clean Cars web portal.

Rulemaking Activity

ARB's Climate Change Program Logo

Rulemaking to consider amendments to new car greenhouse gas emission standards for model years 2012-2016 and permit compliance based on federal greenhouse gas emission standards (February 2010)

ARB Board-approved amendments to the originally proposed regulatory text for new car greenhouse gas emission standards and test procedures for 2001 and subsequent model passenger cars (December 2009)

ARB Board Adopted Regulation (September 2004)

Latest News!

Technical Assessments

Interim Joint Technical Assessment Report (U.S. EPA, NHTSA, ARB)

Addendum to February 25, 2008 - Enhanced Technical Assessment:

Enhanced Technical Assessment:

Addendum to January 2, 2008 - Technical Assessment:

Technical Assessment:

Fact Sheets

Related Efforts

Archive of Public Meetings

For questions regarding Clean Car Standards (Pavley, AB 1493), please contact: Shobna Sahni at (626) 450-6104