CSB: Runaway Reaction Led to Fatal 2024 Explosion at Kentucky Facility
The November 2024 explosion at a Louisville, Kentucky, facility that manufactured caramel coloring for foods and beverages resulted from a runaway reaction in a reactor vessel, according to a final report released yesterday by the Chemical Safety and Hazard Investigation Board (CSB). The incident at Givaudan Sense Colour killed two workers and seriously injured three others.
The reactor vessel was producing caramel coloring for a food product at the time of the incident. CSB determined that a runaway decomposition reaction involving the sugar used in the coloring caused an increase in pressure that the reactor’s pressure relief system could not mitigate. The resulting explosion caused approximately $30 million in damage to the facility, including to the control room, which was not designed to withstand a blast of that magnitude. The workers who died were in the control room.
Nearby homes and businesses sustained an additional $10 million in damages, according to CSB. The blast launched the 2,000-pound reactor shell 250 feet into the surrounding community. Other debris traveled as far as 400 feet beyond the facility’s fence line.
The agency found that the facility’s caramel coloring process required an emergency pressure relief system approximately four times larger than the one in use.
“This tragic incident was a catastrophe waiting to happen,” said Steve Owens, CSB chairperson. “The reactor’s pressure relief system was not designed to release pressure from a reaction like this, and Givaudan did not recognize the potential for a runaway reaction to happen.”
In addition to improving their pressure relief systems, CSB recommends that Givaudan’s caramel coloring facilities conduct third-party reactivity testing on sugar ingredients, analyze hazards, develop comprehensive process safety management systems, establish alerts for operators, and conduct training on safe operating limits.
For more information, refer to CSB’s report (PDF) and press release.