Health Department, CMU experts release findings of air report after deadly explosion at U.S. Steel's Clairton Coke Works

No immediate health risks were measured following the Aug. 11 explosion at U.S. Steel’s Clairton Coke Works, according to preliminary air monitoring results released Friday by the Allegheny County Health Department.

Two workers were killed and 10 others were taken to area hospitals after a trio of explosions damaged Clairton Coke Works, the nation’s largest coke manufacturing facility.

The air monitoring results were from mobile air units provided by Carnegie Mellon University and Pennsylvania’s Department of Environmental Protection that were stationed in the Mon Valley shortly after the explosion.

DEP monitoring equipment in the area showed that short-term exposure limits did not exceed U.S. Environmental Protection Agency standards, the Allegheny County Health Department said

However, the DEP did measure concentrations of air toxics like formaldehyde, ethyl benzene and xylene at the fence line, but those concentrations were only observed for a brief time period and were mostly undetectable throughout most of the testing periods, the department said.

This could indicate health risks, and the health department officials are still evaluating the DEP report and other data to determine if there are any potential issues.

Carnegie Mellon’s data is still being processed, but the preliminary results from showed no specific hot spots tied to the explosion, the health department said.

And the results were generally consistent with data from the health department’s regulatory monitoring network.

Once Carnegie Mellon submits its finalized data, the health department will post the information to its website.

In an effort to more broadly understand pollutant levels near Clairton Coke Works, the health department said it and its partners detected compounds, including hydrocarbons and air toxics known to be associated with coke production.

“These compounds have been observed previously through fence line and permanent monitors and are included in the annual emissions inventories for the Clairton facility,” the health department said.