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Knozone Action Day: What is it?

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Posted at 4:22 PM, Sep 17, 2022
and last updated 2022-09-17 16:22:16-04

In Indiana, the Office of Sustainability usually issues air quality alerts known as "Knozone Action Days".

"Knozone Season” in central Indiana runs from March through October, as ground-level ozone is more prevalent during the warmer months.

A Knozone Action Day means the air quality may become unhealthy for everyone, but certain groups including children and elderly should avoid spending a lot of time outside.

"Ground-level ozone is formed when sunlight and hot weather combine with vehicle exhaust, factory emissions, and gasoline vapors," according to IDEM. "Ozone in the upper atmosphere blocks ultraviolet radiation, but ozone near the ground is a lung irritant that can cause coughing and breathing difficulties for sensitive populations."

The Office of Sustainability asks that everyone look to reduce their outdoor activity - especially strenuous exercise - on Action Days, but certain groups may be more affected than others.

These include but are not limited to:

  • Children
  • The elderly
  • People with lung-related illnesses
  • Those who are especially active outdoors

They also offer a list of ways to help combat high levels of ozone and air pollution on Knozone Action Days including:

  • Refuel vehicles after 7pm. When you pump gasoline into your car tank or a gas can, some escapes as fumes. On hot summer days, these emissions can react with sunlight and heat to form ground-level ozone. Refueling after 7 pm prevents emissions from escaping during the hottest hours of the day when they’re most likely to form ozone.
  • Delay using powered lawn equipment - including mowers - until after 7 pm. Someday, hopefully soon, we may see our energy grid powered completely by renewable energies like wind and solar. Until then, though, anything that runs on power - gas, electricity, etc. - run on fossil fuels at some level and releases emissions when used.
  • Don’t let your vehicle idle. Letting your car idle for longer 10 seconds release more emissions than simply restarting. Avoid heavy traffic times, drive-thru lanes, and any other idling on Action Days.
  • Choose a cleaner commute. Walk, ride a bike, take public transit or hitch a ride with a carpool to prevent or minimize emissions from driving.
  • Set the thermostat a couple degrees higher. Not only is it easier on your utility bill, saving the energy it takes to run your AC full blast reduces emissions and ozone.
  • Combine errands to reduce trips back and forth. You’ll save emissions and time. It’s a win-win.
  • Delay your use of garden, household, and workshop chemicals until the air has returned to healthy levels. Some contain VOCs that may react with sunlight and heat to form ozone.
  • Tell others about Knozone Action Days and how they can help. Central Indiana is our home. It belongs to all of us, and preserving the quality of our air is our shared responsibility. Pass this information along to your friends and family, and tell them about ways they, too, can make a positive impact.