On Aug. 11, 2025, an explosion at U.S. Steel’s Clairton Coke Works outside Pittsburgh — a 392-acre riverside industrial facility and the largest of its kind in the Western Hemisphere — killed two U.S. Steel workers and injured 11 others, according to the Chemical Safety Board, a federal agency investigating the incident.
Six months later, workers remain rattled and community concerns about air pollution from the plant are heightened. The blast comes on top of a string of other accidents at the Clairton plant and a history of legal battles between U.S. Steel and Allegheny County regulators. Some current and former workers at Clairton Coke Works say poor management and underinvestment have exacerbated air pollution and undermined workplace safety at the plant. And the August blast came after Nippon Steel’s $15 billion acquisition of U.S. Steel in June 2025. Nippon Steel did not provide a response to written questions.
