Indianapolis Declares First Knozone Action Day for 2026

The Indianapolis Office of Sustainability has issued a Knozone Action Day for Central Indiana, effective June 4. The alert is due to high ground-level ozone levels, creating “Unhealthy for Sensitive Groups” air quality conditions (Orange level).

Sunny skies, light southwest winds, and an overnight pollutant build-up make conditions ideal for ozone formation. People in Central Indiana with asthma, COPD, or other respiratory and heart conditions should avoid outdoor activity as much as possible. This is the first Knozone Action Day declared in 2026.

According to the Office of Sustainability, approximately 1 in 5 Marion County community members, including children, older adults, pregnant individuals, and anyone suffering from chronic respiratory or heart conditions, is at greater risk for severe symptoms due to unhealthy air quality.

Ground-level ozone is created when a chemical reaction occurs between sunlight and emissions from common urban sources like gas-powered vehicles and lawnmowers.

Protect Yourself and Your Community

Every day, and especially on Knozone Action Days, residents are encouraged to take simple steps to reduce ground-level ozone, including:

• Avoid Idling: Reduce vehicle idling, especially in drive-thru lanes.
• Drive Less: Opt for active transportation like walking, biking, or public transit.
• Fuel Consciously: Delay refueling or using gas-powered lawn equipment until cooler evening hours.
• Conserve Energy: Turn off unnecessary lights and set air conditioning to 75 degrees or above.

Community members can sign up for text or email alerts at smogwatch.in.gov to be notified of unhealthy air days early. Knozone.com and the EPA’s AirNow website are also resources for monitoring local air quality. You can also follow @SustainIndy on social media for updates.