Thomas Zahnow, 50, died Wednesday from injuries he suffered during a Sept. 19 explosion.

Four Axiall workers were performing a maintenance operation when they were exposed to a caustic soda solution. At the time, two of the victims were flown to West Penn Burn Center in Pittsburgh via medical helicopter. A third patient was taken to Wetzel County Hospital by ambulance, while a fourth employee was released following on-site medical treatment.

Zahnow was one of the two workers sent to the West Penn Burn Center after suffering chemical burns on his neck, arms, legs and torso. He had been hospitalized since the incident.

Axiall expects the other three employees to make full recoveries.

“We are mourning the loss of one of our senior employees,” plant manager Jerry Mullens said. “Our whole team is devastated by this loss. Our thoughts, prayers and support continue for the family.”