The Shelby County Health Department issues air quality alerts when air quality is deemed unhealthy for sensitive groups. Forecasts can range from good to hazardous quality according to the air quality index which is accessible on Once air quality has reached Code Orange or higher, it is deemed unhealthy for sensitive groups (which includes people with lung disease, older adults, and children) and an ozone alert is issued for Shelby County.  

When the Health Department issues an ozone alert, the public should seek to stay indoors as much as possible, shorten commutes by car or use carpool or public transportation. To encourage people to take public transportation during ozone days, MATA reduces base fares to 25 cents for passengers boarding fixed-route buses, trolleys and MATAplus vehicles. 

Please note: Ozone days are not forecast according to how hot the temperature at the given moment. Poor air quality is the determining factor for ozone alerts and is attributed to high pollution levels in the air. Using public transportation instead of driving multiple cars (which can emit a number of emissions) is just one way that Shelby County residents can help reduce air pollution.


Ozone alerts are communicated via social media (MATA reshares content from the Health Department) on its Facebook and Twitter pages. Information is also shared by local news media.