CSB Publishes Interim Recommendations in Coke Explosion Investigation
Yesterday the Chemical Safety Board (CSB) announced that they were taking the unusual step of publishing two safety recommendations relatively early in their investigation of the fatal explosion and fire at the U.S. Steel Clairton Coke Works on August 11th. 2025. The CSB published an initial description of the incident on September 29th, 2025. The final report on this investigation, when completed, may contain additional recommendations.
Yesterday’s action brings the total number of CSB investigation recommendations to 1027, with 121 recommendations still open. Currently there are nine open CSB investigations, including the Coke Works inquiry.
The Recommendations
Yesterday’s announcement notes that:
“Although the CSB’s investigation is in its early stages, the agency already has identified potentially unmitigated hazards for workers at Clairton Coke Works that warrant immediate attention. The CSB’s interim recommendations are intended to address those potential hazards.”
Thus, the Board has issued two recommendations to US Steel:
2025-03-I-PA-1 - Conduct a siting evaluation for all occupied and potentially occupied buildings at the Clairton Coke Works facility. Utilize the guidance contained in the Center for Chemical Process Safety’s Guidelines for Evaluating Process Plant Buildings for External Explosions, Fires, and Toxic Releases, the American Petroleum Institute’s Recommended Practices 752, 753, and 756, and other industry good practice guidance documents.
2025-03-I-PA-2-PA-2 - Using the results from the evaluation performed in 2025-03-I-PA-R1, ensure that all documented facility siting hazards are mitigated in accordance with the guiding principles contained in the American Petroleum Institute’s Recommended Practices 752, 753, and 756.
The Interim Recommendations document provides the following recommendation background discussions:
Incident background,
Regulatory requirements,
Industry guidance, and
Basis for recommendations.
The CSB notes (pg 9) that as part of its facility reconstruction efforts, US Steel “is relocating the Battery 13/14 control rooms and the relevant personnel to a building located approximately 100 feet away from the transfer area, which the company selected because the building was not physically affected by the August 11, 2025, explosion.” It also reports (pg 10) that “U.S. Steel informed the CSB in writing that it has not conducted a building or facility siting evaluation as part of its efforts to reconstruct and/or relocate its personnel facilities.” That is apparently the reason that the CSB is publishing these recommendations at this time.