The EPA's Air Quality Index can tell you whether breathing outside air can be harmful. Here's how to read the scale to plan ...

If you're seeing a thick haze outside your window, it's likely air pollution. Here's how to find out what the air quality is near you.

An air quality alert has been issued for all of Michigan for Sunday and Monday due to smoke from Canadian wildfires.

A haze of wildfire smoke engulfed Toronto on Monday morning, pushing the city's air quality to some of the worst on the globe ...

The EPA's Air Quality Index can tell you whether breathing outside air can hurt you. How to read the scale.

You’re not imagining that campfire smell — thick smoke from Canadian wildfires has settled over Minnesota again, with air ...

The EPA's Air Quality Index can tell you whether breathing outside air can hurt you. How to read the scale.

What is the Air Quality Index? The Air Quality Index reflects the density of five pollutants in the air: ground-level ozone, particulates, carbon monoxide, nitrogen dioxide, and sulfur dioxide.

Columbus' air quality is yet again expected to dip into "unhealthy for sensitive groups" levels on June 12.

The U.S. Air Quality Index (AQI) is the Environmental Protection Agency’s tool for reporting outdoor air quality and health.

Canadian wildfire smoke lingers over the Greater Lansing area on June 6. The entire Lower Peninsula is under an air quality advisory.

The index ranges from green, where the air quality is satisfactory and air pollution poses little or no risk, to maroon, which is considered hazardous.