The Louisville Metro Air Pollution Control District has issued an Air Quality Alert for ozone in Louisville and Southern Indiana on Thursday and Friday.
The air pollution could affect sensitive groups including young children, the elderly and people with respiratory ailments like asthma and COPD.
Officials say the general public is not likely to be affected.
APCD recommends that on air quality alert days, people take steps to avoid pumping excess pollution into the air.
Regulators suggest taking public transportation, not using gas-powered lawn mowers and combining your errands into one trip.
This post has been updated.