MIchigan's air quality will be unhealthy for some groups Friday. Check the air quality index map to see if it's good or bad ...

An air quality alert was issued by the National Weather Service in-Sullivan at 1:52 p.m. on Wednesday, July 23.

The National Weather Service has issued an air quality alert due to heavy wildfire smoke from Canada. According to NWS models ...

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 ...

AirNow and PurpleAir use the Air Quality Index, or A.Q.I., a measure of air quality from 0 to 500 that is composed of six categories, from “good” to “hazardous.” ...

Unhealthy Air Quality Index level. Red: Indexes in the 151 to 200 range are considered "unhealthy." At this level, any member of the general public becomes susceptible to health effects.