State officials have issued a “Code Orange” warning for air quality in the Triangle on Thursday, meaning ozone levels could make it difficult for children, older adults and other sensitive groups to breathe.
It’s the first Code Orange forecast the state has issued for the Triangle all summer and it comes at a time when ozone usually ceases to be a problem. Ozone is the main ingredient in smog and is produced when heat and sunlight interact with nitrogent oxides – pollutants that result from the burning of fossil fuels.
State officials predict that hot, sunny weather Thursday will push ozone levels in the Triangle and Charlotte above the federal standard of 75 parts per billion averaged over eight hours.
Ozone concentrations that high have become rare in North Carolina, thanks to lower emissions from power plants, factories and cars. Ozone levels have exceeded the federal standard somewhere in the state only three days in the past three years, according to the Division of Air Quality; in 1999 alone, ozone in the state exceeded the standard 111 times.
State officials urge people who are sensitive to air pollution to avoid moderate exertion outdoors Thursday. Showers and thunderstorms should help clear the air on Friday and Saturday.