An explosion at the largest coke manufacturing facility in the United States injured at least 15 people and forced a partial suspension of the U.S. Steel operations in Clairton, Pennsylvania, media reported.
There was a fire in No. 2 B battery and apparently there was flammable gas that ignited and exploded, Robert Szymanski, director of the U.S. Occupational Safety and Health Administration office in Pittsburgh, told the Pittsburgh Post-Gazette.
The injured were taken to area hospitals, University of Pittsburgh Medical Center spokeswoman Gloria Kreps told the newspaper.
A spokeswoman for U.S. Steel confirmed there was an explosion and fire that resulted in injuries at the Clairton plant. But she declined to give numbers or confirm any disruption of operations, saying only that the company would assess 'the extent of repairs and impact on operations' later.
The Clairton plant is the largest coke manufacturing facility in the United States, operating 12 coke oven batteries and producing approximately 4.7 million tons of coke annually, U.S. Steel said on its website. The plant serves the commercial coke market plus U.S. Steel's steelmaking facilities.
Coke is made from coking, or metallurgical, coal and is used to make steel along with iron ore.
All operations have been shut down at the B battery, the largest coke-making battery at the Clairton complex with 75 ovens, Jim Thompson, manager of the Allegheny County Air Quality Program, told the Post-Gazette.
He said a Health Department inspector was in a trailer about a quarter mile from the blast.
'He said the windows of the trailer were rumbling pretty good when the explosion happened,' Mr. Thompson said.
Video from WPXI television showed smoke rising from the sprawling plant and the area swarming with emergency workers.
Representatives of the Clairton Fire Department declined to comment.
A September explosion at the plant killed a maintenance contractor in a gas cleaning area, the Post-Gazette said.
Joanne Panza, 64, who was standing at the northern end of the plant near her house, told the Post-Gazette she noticed the coke works' hallmark smell became strikingly more pungent.
'I can tell you this, I smell it. It's better now, but it was a bad chemical smell before. The air seems to have cleared,' Panza said.
U.S. Steel Corp stock was up 2 percent at $43.46 in afternoon trading on the New York Stock Exchange.