U.S. Chemical Safety Board releases preliminary findings into deadly U.S. Steel plant explosion
More than a month after the deadly U.S. Steel Clairton plant explosion, investigators are revealing new insight into how it happened.
According to preliminary findings from the U.S. Chemical Safety Board, a gas isolation cast-iron valve was the source of the deadly tragedy.
"The normal phase of the valve is, and they were going to close the valve and then reopen it." Bill Steiner, from the U.S. Chemical Safety Board, said. "The exercising of the valve that day was an activity in preparation for a scheduled job the following week."
Investigators say employees were working to close and reopen a gas isolation valve in the basement of the battery transfer area.
When they tried to flush the valve seat with water, gas monitors began alarming. Evacuations were ordered, and less than a minute later, the explosion occurred.
"We are looking at several characteristics of the operation, the age of the valve being one of them. The value has been identified as a component of evidence that will be subject to testing," explained Stephen Klejst, also from the U.S. Chemical Safety Board.
The board says the valve body had split open and that the valve was manufactured more than 70 years ago. It had been refurbished in 2013.
The next step in the investigation is to access the internal components of the valve.
"There are components in the industry that are aging, and we want to understand whether or not that had a contribution to them," said Klejst.