Other counties reporting smell & haze: The City of Atlanta says fire personnel and Hartsfield-Jackson airport personnel are conducting air quality testing. Many in Gwinnett County have reported a haze and smell, and Gwinnett County Public Schools has canceled outdoor activities for Monday, Sept. 30, and cut outside air from coming into buildings.

CONYERS, Ga. — A large chemical fire broke out early Sunday at a lab in Conyers and has been sending a jarring plume of black smoke into the air all day, with much of the city in an evacuation zone. RELATED: 'I was very, very startled' | Resident describes early morning wake-up from police, evacuation over Conyers chemical fire

BioLab is a company that makes pool and spa treatments, and the chemicals involved in that process appeared to exacerbate the fire and send up huge smoke clouds. The fire later reignited around noon, according to authorities, and was put out around 3:30-4 p.m. on Sunday.