Abstract: At approximately 1:40 a.m. on December 12, 1996, Employee #1, the refrigeration manager, arrived at the plant in response to reports of problems with the Frick 2 cylinder. 8 by 8 enclosed VSA refrigerator compressor, serial #HA55248. The problems had been identified and reported by a security guard working the 11:00 p.m. to 7:00 a.m. shift. Employee #1 was briefed by the security guard and then went to examine the ammonia refrigeration system equipment in the engine room of the plant. Approximately 10 minutes later, the security guard, who was in his guard shack, heard an explosion and saw a cloud rise above the main plant building. The compressor had ruptured, releasing ammonia. Employee #1 was found by the security guard in another building next to a water fountain and hand washing sink. He had been working in the small engine room and suffered extensive chemical burns. Employee #1 was killed. Subsequent investigation revealed that a section of the crankcase housing wall had blown out, discharging a mixture of refrigeration oil and ammonia. It is not known what caused the compressor to rupture.