(File Photo: Source for Photo: U.S. Steel’s Clairton Coke Works in Clairton, Pa., on Wednesday, Oct. 29, 2025. (Quinn Glabicki/Pittsburgh’s Public Source via AP)
HARRISBURG, Pa. (AP) — A federal safety agency investigating an August blast at a U.S. Steel plant near Pittsburgh that left two workers dead said it found a series of incomplete, outdated or inadequate procedures and practices that “exposed” employees to the explosion, which happened as workers were flushing a gas valve.
The Occupational Safety and Health Administration fined the company a total of $118,214 and issued 10 citations.
The blast also injured 11 others, including contractors, according to the Chemical Safety Board, a federal agency investigating the explosion.
Before the August blast, Clairton Coke Works had a history of accidents and explosions, and some current and former workers there say poor management and underinvestment have exacerbated air pollution and undermined workplace safety, Pittsburgh’s Public Source and The Associated Press have found.
U.S. Steel has said the explosion happened when workers were flushing a gas valve in preparation for routine planned maintenance at the sprawling riverside industrial facility, the largest of its kind in the Western Hemisphere.
The valve ruptured and released combustible coke oven gas, OSHA said.
In the 16-page report dated Monday, OSHA said that U.S. Steel’s written procedures, practices and training to safely maintain equipment and flush the gas valve were incomplete, outdated or inadequate.
Those shortcomings, it said, “exposed” employees to an explosion or explosion hazard when the valve ruptured. Another citation said the U.S. Steel didn’t provide required records within a specified time frame after the explosion.
U.S. Steel, in a statement, said it was reviewing the OSHA report. It did not say whether it agreed or disagreed with the findings, or whether it would dispute them.
“We will continue our dialogue with OSHA and other agencies involved,” it said.
The company has said that safety is a core value and shapes its culture.
OSHA gave U.S. Steel deadlines to fix the perceived shortcomings. The agency lets a company contest the findings in an informal conference.
In a statement, the United Steelworkers’ district director, Bernie Hall, said the union was “grateful to OSHA for thoroughly investigating the tragic incident that cost two lives and impacted many others.”
“We are dedicated to working with management to implement OSHA’s recommendations — especially those that incorporate process safety management — and continue our mission to make our workplaces safer,” Hall said.
The Chemical Safety Board has said it continues to investigate.
Kurt Barshick, U.S. Steel’s vice president of the Mon Valley Works, said during an October presentation to area residents that workers trapped “3,000 PSI water inside of a valve that’s rated for 50 PSI.” The valve cracked and gas filled the area, Barshick added.
The blast came on top of a string of other accidents at the Clairton plant over time, as well as a long history of legal battles between U.S. Steel and Allegheny County regulators, who regularly accuse the company of flouting environmental rules at the facility.
