EPA Releases New Standard for Ground Level Ozone

On October 1, 2015, EPA announced a final rule revising the National Ambient Air Quality Standard (NAAQS) for ground-level ozone. The new standard, set at 70 ppb, replaces the ozone standard revision made in 2008 and lowers the Code Orange and above ranges on the Air Quality Index (AQI), EPA’s color-coded tool for communicating daily air quality, in order to better protect public health.

The purpose of EPA’s latest revision is to strengthen the standard to make it more protective of public health and welfare. Scientific research reviewed by EPA gives evidence that ozone causes bronchitis, aggravates asthma, and hospital and emergency room visits, among others. In addition, new scientific evidence shows that repeated exposure to ozone damages sensitive vegetation and trees leading to increased susceptibility to disease, pests, and damaged foliage.

With the new standard, the Metropolitan Washington-Baltimore region is anticipating an increase in the number of Code Orange and Code Red air quality days (days that surpass the national standard level for safe or healthy air quality); poor air quality days will likely double this season. This increase will require residents to take action more frequently in order to reduce air pollution and protect the health of area residents.

Despite the new standard, the air quality in the metropolitan Washington-Baltimore region has improved over the past decade. This is due in part to federal, state and local government regulations and pollution control programs, continuous public education and outreach on air quality, as well as increased voluntary efforts taken by participants and members of the Clean Air Partners program.

More than 7 million people in the metropolitan Washington-Baltimore region live in areas that exceed EPA’s standards for ground-level ozone and particle pollution. Sensitive groups, made up of 1.5 million area residents, are people with lung disease (asthma, emphysema, and chronic bronchitis), children, older adults, and people who are active outdoors and who may experience adverse health effects when air pollution levels are elevated for a prolonged period of time. EPA and Clean Air Partners recommend that during a Code Orange or above day, sensitive groups should limit their outdoor activity level and everyone should follow actions to reduce air pollution. Recommended actions include driving less by postponing errands, teleworking, carpooling or taking public transit, refueling after dark, and postponing mowing, all of which will impact air quality, improve health and reduce greenhouse gas emissions that impact climate change.

More information on the ozone standard can be found on the EPA Ozone Standard website.