Poor Air Quality Expected for parts of Connecticut, Massachusetts, New Hampshire on June 1, 2023

May 31, 2023

BOSTON (May 31, 2023) – New England state air quality forecasters are predicting air quality that is unhealthy for sensitive groups, due to elevated ground-level ozone, commonly referred to as "smog."  The areas that are predicted to exceed the National Ambient Air Quality Standards for ozone on Thursday, June 1 are: 

Connecticut (Greenwich, Stratford Westport, Middletown, Danbury, and Hartford),Massachusetts (Eastern Norfolk, Suffolk, and Essex counties) New Hampshire (Seacoast)

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

EPA and the medical community advise people to limit any strenuous outdoor activity when poor air quality is expected. Also, everyone can take steps to keep air emissions down during air quality alert days.  As climate change increases the probability of unseasonably warm weather, these kinds of air quality events are predicted to increase in frequency. Communities already vulnerable and overburdened will also be impacted by these kinds of events.

Ground-level ozone forms when volatile organic compounds and oxides of nitrogen (ozone precursors) interact in the presence of strong sunshine. Cars, trucks, and buses 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 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).

More information:

Real-time Particulate Matter data and air quality forecasts New England Air Quality Index

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

Air Quality Alerts EnviroFlash

EPA's ENERGY STAR Program