The U.S. Chemical Safety and Hazard Investigation Board provided an update Monday on its investigation into the fatal U.S.

CSB updates on the fatal explosion at U.S. Steel Clairton Coke Works, focusing on the role of an old valve in the incident.

Carbon monoxide and gas alarms were triggered leading up to fatal explosion at the U.S. Steel Clairton Coke Works site Aug.

Federal investigators have uncovered new details about the moments leading up to the deadly Clairton Coke Works explosion.