An oil refinery worker exposed to propane and acid at a Valero plant in Memphis died on Monday, officials said.
He was the second person to die this year from an on-the-job injury. A worker died from injuries in a fire at the refinery, which has been cited for violations related to the safe handling and control of hazardous energy and chemicals, officials said.
Firefighters on Monday morning found two workers injured when a sight glass on a pump unit ruptured, exposing them to a mixture of propane and hydrofluoric acid, said Memphis Fire Department spokesman Wayne Cooke.
Two firefighters also were exposed to the substance, he said. The pump was located at the plant's alkylation unit, Valero Energy Corp. spokesman Bill Day said in a statement.
A sight glass is a transparent tube or window that allows workers to monitor fluid levels within a tank, pipe, pump or boiler.
One of the Valero workers died at the hospital, said Martha Deacon, a spokeswoman for the Tennessee Department of Labor and Workforce Development. She did not have details on the time or cause of the death. The other worker, who was a contractor, and the two firefighters were taken to a hospital in non-critical condition.
The company said there was no explosion or fire, and no refinery operations were affected. The refinery has notified regulatory agencies and the accident remains under investigation, Day said.
In March, three contract workers were seriously burned in a fire at the plant, and Nicolas Cuevas later died of his injuries.
A relative of Cuevas filed a multimillion-dollar wrongful death and injury lawsuit against San Antonio-based Valero in April. The suit claims that there was a failure to ensure that there were no hazardous or flammable gases in a flare line and there was a failure to provide timely firefighting assistance.
Cooke said at the time that the fire was extinguished before firefighters arrived.
A Tennessee Occupational Safety and Health Administration inspection done after the fire cited the plant for nine serious violations and fined it $63,000.
The violations were related to the process of safety management of highly hazardous chemicals and control of hazardous energy, according to the inspection report.