New England Experienced Fewer Unhealthy Air Quality Days During 2019 Ozone Season
David Deegan (News Media Only)
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October 3, 2019


New England Experienced Fewer Unhealthy Air Quality Days During 2019 Ozone Season

BOSTON – The U.S. Environmental Protection Agency (EPA) today confirmed that New England states experienced fewer days with unhealthy air quality this year, compared to 2018. Based on preliminary data collected between March and September 2019, there were 24 days when ozone monitors in New England recorded ozone concentrations above levels considered healthy versus 28 in 2018.

The number of unhealthy ozone days in each state this summer (as compared to last summer) are as follows:

  • 21 days in Connecticut (23 in 2018)
  • 5 days in Massachusetts (12 in 2018)
  • 2 days in Rhode Island (12 in 2018)
  • 1 day in New Hampshire (6 in 2018)
  • 1 day in Maine (3 in 2018)
  • 0 days in Vermont (1 in 2018)

“We can all feel proud of the progress we have made in reducing ozone pollution over the past several decades,” said EPA Region 1 Administrator Dennis Deziel. “There is still work to be done, as especially in some parts of southern New England, we continue to experience too many days with unhealthful air quality.”

Ground-level ozone is formed when volatile organic compounds and nitrogen oxides chemically react in the presence of sunlight. In New England, cars and trucks emit most of the pollution that makes ozone. Fossil fuels burning at electric power plants, which run at high capacities on hot days, emit substantial amounts of ozone-making pollution. Gasoline refilling stations, print shops, household products like paints and cleaners, as well as gasoline-powered lawn and garden equipment also contribute to ozone formation.

The number of unhealthy days (when ozone concentrations exceed the 0.070 parts per million standard) vary from year to year, due to weather conditions. Hot, sunny, summery weather is conducive to ozone formation. For 2019, a cool, wet spring lead into an average New England summer. Since 1983, New England has experienced a decrease in the number of unhealthy ozone days – from 118 in 1983 to only 24 in 2019. This downward trend is due to a reduction in emissions that form ozone. Although the 2019 ozone season is ending, it is important to note that pollution from small particles in the air is a year-round concern.

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