An official website of the United States government

Here’s how you know

Official websites use .gov A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS A lock (LockA locked padlock ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

JavaScript appears to be disabled on this computer. Please click here to see any active alerts.

 BOSTON (August 3, 2022) –The U.S. Environmental Protection Agency (EPA) and New England state air quality forecasters are predicting air quality that is "unhealthy for sensitive groups," due to elevated levels of ground-level ozone, commonly referred to as "smog."

The areas that are forecasted to exceed the Federal air quality standard for ozone on Thursday, August 4, include Southwest and Central Connecticut, parts of Central and Northeast Massachusetts, and Southeast New Hampshire.

These locations are subject to change, so please refer to EPA New England's webpage for current air quality conditions and forecasts across New England.

With hot, summery weather, EPA and state air quality forecasters predict areas of unhealthy air quality in several areas of New England tomorrow. EPA and the medical community advise that people limit any strenuous outdoor activity when poor air quality is expected.

Ground-level ozone forms when volatile organic compounds (VOCs) and oxides of nitrogen (ozone precursors) interact in the presence of strong sunshine. Cars, trucks, buses and other large combustion sources emit most of the pollution that creates ozone. Emissions from gasoline stations, print shops, household products, like paints and some cleaners, as well as lawn and garden equipment also add to the ozone formation.

Exposure to elevated ozone levels can cause breathing problems, aggravate asthma, and other pre-existing lung diseases, and make people more susceptible to respiratory infection. When ozone levels are elevated, people should refrain from strenuous outdoor activity, especially sensitive populations such as children and adults with respiratory problems.

When ozone is forecast to be "unhealthy for sensitive groups," members of the public are encouraged to help limit emissions and reduce ozone formation by:

During poor air quality events, it is also important to reduce household energy usage, such as setting air conditioners to a higher temperature, turning off unnecessary lights, equipment, and appliances. EPA's ENERGY STAR Residential Program also provides trusted guidance and online tools to help homeowners make smart decisions about improving the energy efficiency of their existing homes.

The current ozone standard is 0.070 parts per million (ppm). So far this year, there have been 16 days in New England when ozone concentrations have exceeded the standard.

Preliminary list of this summer's ozone exceedances

Real-time ozone data and air quality forecasts

National real-time air quality data (free iPhone and Android apps)