Workers in coke plants face a range of dangers, including falling and getting pinned by machinery or rail cars.

But explosions are rare, according to an industry official, and U.S. Labor Department statistics suggest that the occupation poses less of an injury hazard than the average job.

Bruce Steiner, president of American Coke and Coal Chemicals Institute, which represents all 20 coke plants currently operating in the United States, said most accidents involve falls or moving machinery. "Very rarely is there an explosion accident," he said.

Wednesday's explosion at the U.S. Steel Clairton coke plant was the second there in less than a year. A contractor's employee, Nicholas Revetta, 32, of Clairton, was killed in a Sept. 3 blast and a second contract worker was injured.

According to the federal Bureau of Labor Statistics, 11 fatalities occurred in 2008, the last year for which statistics were available, at facilities classified as petroleum and coal products manufacturers. That category includes coke plants. There were seven deaths in 2007 and nine in 2006.

Non-fatal workplace illnesses and injuries at such facilities occur at rates below the national average for all private industry.

In 2008, there were 3.9 incidents per 100 full-time employees in private workplaces nationwide; at petroleum and coal products facilities the rate was 1.9 per 100.

Online records from the federal Occupational Safety and Health Administration show the Clairton coke plant was inspected in February 2009, with no safety violations listed.

The most recent record of a safety violation was in 2006 for asbestos, and the record shows that U.S. Steel was not fined. It did agree to pay $2,675 in fines in 2005 stemming from other safety violations that OSHA termed "serious."

The Clairton plant is one of four coke-producing facilities in Pennsylvania. The others are in Neville, Monessen and Erie.

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