At 2:45 p.m. on September 19, 2014, two employees, both 50, were replacing a valve in a process line that transported 70% caustic solution of sodium hydroxide (NAOH) from storage tanks to a loading rack.
While they were removing the valve and a stopper plate that had been previously inserted into the line, the employees were sprayed with the caustic solution. The workers suffered chemical burns to their skin and lungs, resulting in their death.