Interim Report on U.S. Steel’s Deadly Clairton Coke Works Explosion Indicated Management Previously Rejected Safety Recommendations

As we continue to advocate for a cleaner, safer Mon Valley, the Group Against Smog and Pollution (GASP) is keeping a close eye on the fallout from the deadly August 2025 explosion at U.S. Steel’s Clairton Coke Works.

In case you missed it, the U.S. Chemical Safety and Hazard Investigation Board (CSB) published an interim report following that issued interim safety recommendations to the company.

You can read the entire document here (and we totally recommend that you do). For those who’d prefer the Clif’s Notes, here’s a breakdown of what the investigators found and why it matters for our community.

The CSB’s findings are…sobering. The explosion happened when coke oven gas leaked and ignited in a transfer area. The board found that the buildings where workers were stationed—including control rooms and break rooms—were simply not designed to protect people from such a blast.

The CSB has issued two main interim fixes:

What’s most frustrating for those of us following U.S. Steel’s safety record is that these aren't necessarily new ideas. The CSB pointed out that industry-standard safety practices for what’s known as facility siting—essentially making sure workers aren't sitting ducks in a blast zone—have existed for YEARS.

In fact, the document notes that some of these specific safety recommendations were, in fact, suggested in the past. Despite those warnings, U.S. Steel management didn't enact those recommended changes.

Here are the receipts:

Now, in the wake of a tragedy, the company has already started rebuilding gas piping in almost the exact same location and layout as before. They are also moving control rooms only about 100 feet away—a move the CSB says might not actually be safe without a real evaluation.

At GASP, we know that worker safety and environmental safety go hand-in-hand. These incidents often lead to massive releases of pollutants and emergency flaring that bypasses pollution controls.

We’re glad to see the CSB stepping in, but it shouldn't take a fatal explosion to get a company to follow basic safety protocols that have been on the books for years.

Editor’s Note: GASP continues to follow this issue closely. We’ll keep you updated as the final report is released.