A shelter-in-place advisory was extended for a Georgia county Monday after chlorine was detected in the air — a result of a fire at a chemical lab that started Sunday.

Rockdale County officials ordered people to evacuate the area near the BioLab plant in Conyers, Ga., and they said others should stay home to avoid the “harmful irritant chlorine.”

More than 90,000 residents in a county east of Atlanta were told to keep sheltering in place Monday and businesses were told to stay closed a day after a chemical plant fire sent a massive plume of dark smoke high into the sky that could been seen for miles.

"If you have concerns, stay inside, close windows and doors, and turn off ventilation systems,” Atlanta's mayor advised

Dangerous chlorine was detected in the air and officials told nearly 100,000 residents to 'turn the air conditioning off and keep windows and doors shut.'