Firefighters were called around 5:30 a.m. to the Giant Food Store located on the 1700 block of Dekalb Pike after an alarm was activated inside the grocery store.
Arriving crews took carbon monoxide readings in the store and detected elevated readings inside of the 24 hour grocery store.
It is not known how many people were inside when firefighters arrived, but EMS crews evaluated 15 people at the scene for any symptoms of carbon monoxide poisoning.
There were no reports of anyone having been transported to the hospital.
The store was later given the all clear and resumed normal service.