INDIANAPOLIS, Ind. -- The Indiana Department of Environmental Management has announced that Thursday will be an Air Quality Action Day, as high ozone levels are being forecasted statewide.

34 Indiana counties are under the Air Quality Action Day including LaPorte, St. Joseph, and Elkhart.

Air Quality Action Days occur when light winds, hot and dry air, stagnant conditions, and lower atmospheric inversions trap pollutants close to the ground.

Ground-level ozone is formed when sunlight and hot weather combine with vehicle exhaust, factory emissions, and gasoline vapors. 

Ozone in the upper atmosphere helps block ultraviolet radiation, but ozone near the ground can be a lung irritant that can cause coughing and breathing difficulties for sensitive populations.

IDEM encourages Hoosiers to reduce ozone by driving less, avoiding refueling, engine idling, and using gasoline-powered equipment until after 7 p.m., and turning off lights and keeping the thermostat at 75 degrees or above.

Anyone sensitive to changes in air quality may be affected when ozone levels are high, and IDEM recommends that children, the elderly, or anyone with heart or lung conditions avoid exertion or heavy outdoor work.

Visit www.SmogWatch.IN.gov to learn more about ozone and sign up for air quality alerts.