Millions warned to avoid drive-thru lanes

Indiana environmental officials issued a statewide Air Quality Action Day as ozone levels are expected to reach “Unhealthy for Sensitive Groups.” Residents were told to avoid drive-thrus, reduce idling, and limit certain outdoor and everyday activities, with g

For millions of people in Indiana, the warning arrived in the small choices of an ordinary day: the next time you were about to pull into a drive-thru, you were being asked to slow down and rethink it.

On Thursday, the Indiana Department of Environmental Management declared an Air Quality Action Day effective across nearly the entire state, covering roughly 7 million residents. The alerts remained in effect until midnight local time, as ozone pollution was expected to reach unhealthy thresholds.

The guidance is aimed at protecting people who are most vulnerable to air pollution. The state’s alert said ozone levels are expected to be in the “Unhealthy for Sensitive Groups” range. and that active children and adults. along with people with respiratory conditions such as asthma. should limit prolonged outdoor exposure.

Officials tied the timing to early-summer conditions that make ozone build quickly—warm temperatures. strong sunlight. and air that can remain relatively still. Ozone, they noted, is not something that comes straight out of a pipe. It forms when pollutants from vehicles and other sources react in heat and stagnant air. which makes spikes more likely during hotter stretches.

Among the most striking recommendations was simple and immediate: avoid using drive-thru services. Residents were urged to combine errands into a single trip, carpool, or use public transportation when possible, to reduce emissions during the period when ozone is most likely to surge.

Drivers were also told to cut down on idling. Authorities advised turning off engines when idling for more than 30 seconds, citing vehicle exhaust as a contributor to ozone formation.

The alert stretches across major population centers, including Indianapolis, Fort Wayne, Evansville, and South Bend, along with smaller communities such as Noblesville, Carmel, Bloomington, and Terre Haute. It’s not a narrow notice meant for one corridor—it affects a broad swath of the state.

In parts of southern Indiana, officials issued a Code Orange alert—signaling potential health impacts for sensitive populations—covering areas near Louisville. Authorities said the general public is less likely to be affected, but still advised caution.

The state’s explanation for why the air can turn so fast focused on ground-level ozone. the kind tied to air quality alerts. Ozone is created through chemical reactions involving nitrogen oxides. largely from vehicles and power plants. and volatile organic compounds. from sources such as gasoline vapors. solvents. and industrial emissions. Sunlight supplies the energy that triggers the reactions, allowing the pollutants to recombine into ozone. Because ozone is a “secondary pollutant. ” it builds over time as emissions accumulate—often peaking in the afternoon during summer heat.

Officials pointed to a mix of conditions that can drive the spike: high temperatures, sunlight, and light winds that help pollutants accumulate and react. The result is ground-level ozone, a key component of smog.

Additional steps were laid out beyond avoiding drive-thrus. Residents were asked to delay refueling vehicles or using gasoline-powered lawn equipment until after 7 p.m. when conditions are less favorable for ozone formation. Energy conservation measures were also recommended. including setting air conditioners to 75 degrees or higher and turning off lights when not in use.

The same kind of notice was not confined to Indiana. Similar advisories were issued in areas bordering Ohio and Kentucky. where regional air quality agencies warned that ozone levels could approach or exceed unhealthy standards. Residents there were given parallel guidance: avoid vehicle idling, refuel after evening hours, and postpone yard work using gas-powered equipment.

As for what comes next, officials said the current alert is set to expire at midnight, but conditions could change depending on weather patterns and pollution levels. Residents were urged to monitor updates from IDEM and local air quality agencies.

Public health officials emphasized that small behavioral changes—like skipping a drive-thru stop or combining multiple errands—can add up, especially during critical periods when the atmosphere is primed for ozone to build.

Thursday’s alert fits a broader early-summer pattern across the Midwest, as warmer temperatures and increased sunlight create conditions that can turn routine commutes and everyday chores into potential contributors to smog—unless people respond quickly.

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