Abstract: On August 31, 2007, Employee #1 and Employee #2 were working near the section of piping that had been removed the prior day during the rerouting of an ammonia refrigerant line. The plant coordinator was instructed to transfer ammonia refrigerant into the system, due to communication failures about the line rerouting. When the refrigerant line stop-valve was opened for the transfer, ammonia entered the production area. Employee #1 and Employee #2 were overcome by ammonia vapors and were hospitalized. Employees #3, #4, #5 and #6 were also exposed to unknown levels of ammonia during the release, and were treated at a local hospital. Employee #1 died of injuries sustained in the ammonia release. The employer was a meat product processing plant.