U.S. Steel has released new details on what investigators believe caused the explosion at the Clairton Coke Works plant that ...

"Pressure built inside the valve, leading to valve failure and coke oven gas filling the area and ultimately exploding when ...

U.S. Steel says preparations for a routine maintenance task may have led to an explosion at a U.S. Steel coal-processing ...

The explosion happened when workers were flushing a gas valve in preparation for maintenance on two of the plant's coke oven ...