CSB to Investigate Fatal Incident at U.S. Steel’s Pennsylvania Coke Plant

Aug. 12, 2025

Two workers were killed and several others injured in explosions and fires at a U.S. Steel coking plant in Clairton.

The U.S. Chemical Safety and Hazard Investigation Board (CSB) has opened an investigation into the Aug. 11 explosions and fires at U.S. Steel’s Clairton Coke Works plant in Clairton, Pennsylvania, that reportedly killed two people and injured at least 10 others, according to the agency.

CSB Chairperson Steve Owens said the board will work to determine the cause of the incident and identify measures to help prevent similar events. The Clairton Coke Works facility processes raw coal into coke for steelmaking and covers 392 acres about 15 miles from Pittsburgh. It is considered the largest coking facility in North America, with nearly 1,300 employees reporting daily.

“This is a very serious incident that fatally injured two people and put others at serious risk. It should not have happened and potentially could have been prevented,” CSB Board Member Sylvia Johnson said.

Earlier this month, the CSB also announced an investigation into a fatal dust explosion at a biofuels plant in Nebraska, which reportedly resulted in one death.

About the Author

Amanda Joshi | Managing Editor

Amanda Joshi has more than 18 years of experience in business-to-business publishing for both print and digital content. Before joining Chemical Processing, she worked with Manufacturing.net and Electrical Contracting Products. She’s a versatile, award-winning editor with experience in writing and editing technical content, executing marketing strategy, developing new products, attending industry events and developing customer relationships.

Amanda graduated from Northern Illinois University in 2001 with a B.A. in English and has been an English teacher. She lives in the Chicago suburbs with her husband and daughter, and their mini Aussiedoodle, Riley. In her rare spare time, she enjoys reading, tackling DIY projects, and horseback riding.