Additional Statement on Aug. 11, 2025, Incident at U. S. Steel’s Clairton Plant

August 15, 2025

Following Monday's tragedy at our Clairton Plant, our employees along with other agencies, the USW and third-party experts have been tirelessly investigating, reviewing video footage and interviewing employees. We continue to strive to share information with our affected families and employees first, particularly those in Clairton. Preliminary indications lead us to believe that the explosion happened when flushing a gas valve, in preparation for planned maintenance. Pressure built inside the valve, leading to valve failure and coke oven gas filling the area and ultimately exploding when finding an ignition source. We want to reinforce that this investigation is in its early stages, and we will provide more information when we can. Our focus remains on our employees and their families during this difficult time.