The U.S. Chemical Safety and Hazard Investigation Board (CSB) released an update into its ongoing investigation of an April 8, 2021, incident at the Yenkin-Majestic OPC Polymers resin plant in Columbus, OH.
The update provides a detailed incident description, background information on the facility and production as well as a history of the equipment. The large explosion and fire led to one fatality and injured eight additional employees.
CSB Interim Executive Steve Owens said, “This was a very serious incident which led to a fatality, several injuries, and serious damage to the facility and the surrounding community. This update provides important information about the events leading up to this incident while our investigation is ongoing.”
The update details
The update details events on the night of the incident. Chemical reactions occurred when a process in a unit referred to as Kettle 3 was nearly complete.
The CSB determined that during the addition of a solvent to Kettle 3 an agitator (stirring mechanism) had not been running for over an hour. When a worker realized that the agitator had shut down, he turned it on and the product inside the kettle began to quickly vaporize.
This increased pressure inside the kettle, which continued to rise until a mixture of resin liquid and flammable solvent vapor released from Kettle 3’s manway into the enclosed room where the kettle was located.
Flammable vapor
Flammable vapor spread throughout different areas of the building including the furnace room
As the pressure in Kettle 3 continued to build, flammable vapor spread throughout different areas of the building, including the furnace room, and ignited.
The explosion also ignited flammable material present at the plant which resulted in a large fire. Two employees were rescued from collapsed parts of the plant, one employee was fatally injured, and eight others were transported to area hospitals for injuries.
Key areas
Moving forward the CSB’s investigation will continue to analyze several key areas, including:
- Equipment design
- Process safety management systems
- Regulations, industry standards, and guidance
- Emergency response to a flammable vapor release
Distributing information
Board Member Sylvia Johnson said, “Our investigation is still ongoing. Complete findings, analyses, and recommendations will be available in the agency’s final report. In the interim, the CSB’s goal is to distribute information on our ongoing work as it becomes available.”
The CSB’s core mission activities include conducting incident investigations; formulating preventive or mitigative recommendations based on investigation findings and advocating for their implementation; issuing reports containing the findings, conclusions, and recommendations arising from incident investigations; and conducting studies on chemical hazards.
The agency's board members are appointed by the president subject to Senate confirmation. The Board does not issue citations or fines but makes safety recommendations to companies, industry organizations, labor groups, and regulatory agencies such as OSHA and EPA.
