SACRAMENTO - The California Air Resources Board supports the U.S. EPA’s decision today to strengthen the national ambient air quality standard for ground-level ozone pollution, bringing the national standard more in line with California’s 10-year-old standard.

Strengthening the standard provides health, environmental and economic benefits for all of California. Science demonstrates that adverse health impacts continue to occur with the previous 8-hour average ozone standard level of 75 parts per billion. The U.S. EPA has now lowered the level of the standard to 70 ppb, making it more health protective.

“We support using the most up-to-date science and recognize that even as the new ozone standard gets tougher to attain California will continue to make progress by employing cleaner technology and fuels,” ARB Chair Mary D. Nichols said. “The new standard will mean a reduction in premature mortality, hospitalizations, emergency room visits for asthma, and lost work and school days. This is especially critical in the South Coast and San Joaquin Valley, where nearly two-thirds of our state’s residents live, including large numbers of people who work outside and who have asthma and other chronic heart and lung diseases.”

ARB’s control programs, together with efforts to reduce air pollution at the local and federal levels, have achieved tremendous success in reducing emissions and providing continued improvement in air quality. The South Coast and San Joaquin Valley are the nation’s only two air basins designated ‘extreme’ nonattainment.

Further reductions are needed to meet the new standard -- and California’s air quality and climate goals. With a standard of 70 ppb, several rural counties likely will fall out of attainment, adding to the state’s existing 16 ozone nonattainment areas. New nonattainment areas are expected to include Amador, Tehama and Tuolumne counties and the Sutter Buttes area.

One of several goals California must meet are the existing ambient ozone air quality standards in 2023 and 2031, which will require an estimated 80 percent reduction in oxides of nitrogen (NOx) emissions below current emission levels in the South Coast air basin, with substantial reductions needed in the San Joaquin Valley and other nonattainment areas of the state.

New draft strategy released
In a just-released discussion draft of the State’s strategy for its cars and trucks to meet federal air quality standards, the ARB outlines a proposed strategy that continues to build on previous efforts to meet critical air quality and climate goals over the next 15 years. Released Wednesday, the strategy provides a comprehensive foundation for the ongoing transformation of the state’s vehicle fleet putting California on a path to likely meet the new more health-protective federal ozone standard. 

The draft strategy (Discussion Draft Mobile Source Strategy) (https://www.arb.ca.gov/planning/sip/2016sip/2016mobsrc.htm) is designed to provide public health protection for the millions of Californians who still breathe unhealthy air and to help California do its part to slow global warming and reduce its dependence on petroleum. In part, the proposed strategy would:

• Establish requirements for cleaner technologies;
• Ensure in-use performance over the lifetime of the vehicle;
• Increase the penetration of zero-emission technologies for cars, trucks and off-road equipment;
• Require cleaner-burning renewable fuels; 
• Enhance efficiencies in moving people and freight throughout California; and
• Transform the state’s vehicle fleet using zero- and near-zero-emission technologies in order to help meet California’s air quality and climate change goals. 

National low-NOx standard urged
Reducing emissions from heavy-duty trucks – significant contributors to emissions that form ozone -- is an important element of the mobile source strategy. ARB, therefore, urges U.S. EPA to adopt tighter national NOx emissions standards for on-road heavy-duty engines (fueled by either diesel or CNG). NOx, a product of incomplete combustion, contributes to the formation of not only ozone but also fine particle pollution (PM2.5), a serious health threat in California.

ARB will develop new heavy-duty diesel engine emissions standards within the next several years, while simultaneously petitioning U.S. EPA to establish a corresponding national standard, in order to maximize emission reductions from all vehicles operating in California, regardless of whether they were purchased in a different state. 

Vehicles purchased outside of California account for one-third of the heavy-duty vehicle miles traveled in the state on any given day. For that reason, a lower NOx standard that reduces emissions from all trucks operating in California is critical to meeting future air quality goals and tackling this public health challenge.
  
For more information on the new National Ambient Air Quality Standard for Ozone, an ARB fact sheet is available here. (https://www.arb.ca.gov/newsrel/new_ozone_std_factsheet.pdf)

U.S. EPA fact sheet "Working to Reduce Ozone in California". (http://www3.epa.gov/ozonepollution/pdfs/20151001californiafs.pdf) 

The final rule and associated materials are now posted at http://www3.epa.gov/ozonepollution/actions.html (http://www3.epa.gov/ozonepollution/actions.html)