The U.S. Chemical Safety and Hazard Investigation Board (CSB) has released an update on the September 29, 2024, chemical fire at Bio-Lab in Conyers, Georgia.
The incident involved the decomposition of trichloroisocyanuric acid (TCCA) and dichloroisocyanuric acid (DCCA) stored in a warehouse, which led to fires, toxic off-gassing, and significant smoke plumes.
According to the report, a fire watch was in place due to strong chemical odors detected months earlier.
However, at approximately 5:10 a.m. on the day of the incident, employees on-site were unable to isolate reacting chemicals, prompting a 911 call.
The fire escalated, with visible flames appearing by 6:30 a.m., leading to shelter-in-place orders for the surrounding community.
A second fire erupted at noon, releasing thick smoke and prompting evacuations.
Interstate 20 was closed shortly after the collapse of portions of the facility and remained shut until the following morning.
Smaller roads near the plant were inaccessible for weeks.
The Rockdale County Fire Rescue extinguished the initial fire by 8:10 a.m., and the second by 4:00 p.m.
However, chemical off-gassing persisted due to residual TCCA under debris.
Heavy equipment was required to access and neutralize the material.
The incident caused toxic vapor plumes that reached nearby Atlanta, 30 miles away, affecting air quality.
The U.S. Environmental Protection Agency detected chlorine and hydrogen chloride above safe levels until mid-October.
Around 90,000 residents were advised to shelter in place, and 17,000 evacuated.
The EPA ceased air monitoring on October 17, transitioning oversight to the Georgia Environmental Protection Division.
Residents reported lingering health issues, including respiratory irritation and headaches, after exposure to the chemicals.
Rockdale County announced plans to file a federal lawsuit seeking compensation for damages and impacted residents.
Officials also called for the permanent closure of Bio-Lab’s facility in the county.
Meanwhile, the CSB continues to investigate causes, regulatory compliance, and fire protection systems for handling bulk chemical oxidizers.
The Bio-Lab facility, in operation since 1973, was completely destroyed in the incident.
Cleanup and remediation efforts are ongoing, with findings to be included in the CSB’s final report.
The CSB has provided an update on its investigation into the September 2024 Bio-Lab fire in Conyers, Georgia, which destroyed a chemical storage facility.
The incident began with the decomposition of chemicals in a warehouse and resulted in fires, toxic gas releases, and smoke plumes that affected air quality in nearby areas.
Emergency responses included road closures, evacuations, and shelter-in-place orders for weeks.
Air monitoring detected chlorine and hydrogen chloride levels exceeding safety thresholds until October 17.
Rockdale County plans legal action against Bio-Lab and seeks the facility’s closure.
Cleanup efforts and the CSB investigation are ongoing, with a final report pending.
