CSB Video Focuses on 2021 Explosion, Fire at a Resin Plant
A new video released by the U.S. Chemical Safety and Hazard Investigation Board (CSB) features an animation of an April 2021 explosion and fire at a resin plant in Columbus, Ohio, that fatally injured one employee. Eight others were seriously injured, with one worker requiring a leg amputation after being crushed under collapsed debris. According to CSB’s final investigation report on the incident (PDF), released in 2023, the explosion at the Yenkin-Majestic facility “was seen, heard, or felt throughout parts of Columbus,” and the resulting fire burned for about 11 hours. The plant was demolished afterward, and Yenkin-Majestic has estimated that the incident caused more than $90 million in property damage.
The incident began during a batch operation to produce resin. The plant’s system design allowed an operator to add flammable solvent to a kettle, or low-pressure vessel, containing hot resin while the kettle’s agitator was unexpectedly off. This meant that the solvent formed a liquid layer on top of the resin instead of mixing with it. The operator then realized that the agitator was off and turned it back on, which CSB explains led to the liquid solvent vaporizing as it came into contact with the hot resin. The resulting rapid pressure increase inside the kettle “led to the failure of the kettle’s new manway that was installed approximately three months before the incident,” the agency said. After the manway failed, the escaped vapor formed a flammable cloud that spread through the facility and ignited.
“CSB’s investigation determined that Yenkin-Majestic failed to ensure the mechanical integrity of the newly installed manway, which was not adequately designed, constructed, or pressure tested,” CSB Board Member Sylvia Johnson explains in the video. “The company also lacked engineering controls that could have prevented the incident and did not have adequate emergency response preparations in place.”
CSB’s investigation report further describes the facility’s “gap in engineering controls.” According to the agency, Yenkin-Majestic equipped the kettle with several interlocks intended to support its safe operation. But the company did not add an interlock to prevent solvent from being added to the kettle while its agitator was off, which CSB says contributed to what happened during the incident in 2021. The video outlines the safety issue related to the hierarchy of controls as well as issues regarding mechanical integrity of low-pressure vessels and emergency preparedness.
CSB’s new video is available on its YouTube channel. For more information, see the agency’s news release.