Employee #1 was exposed to ammonia gas on November 20, 1984, during an ammonia leak from refrigeration piping in a compressor room. A threaded joint weakened due to excess vibration and cracked. When it failed, ammonia was released. An unapproved gas mask was used by the employee. Employee #1 died the following December 16th from acute bronchopneumonia brought about by inhalational airway and lung injury from the ammonia exposure.