Abstract: At approximately 7:00 a.m. on June 8, 2008, Employee #1 started a cooling process for a ribbon blender containing black cocoa powder. The cooling process utilized large quantities of compressed liquid nitrogen to lower the temperature of the black cocoa powder. The ribbon blender had a ventilation system designed to remove excess nitrogen from the blender safely. However, on that particular day, the ventilation system became compromised. The nitrogen, which entered into the ribbon blender, exceeded the blender capacity and backed up into an attached, unsealed screw conveyor. The nitrogen leaked out of the screw conveyor and into the black cocoa control room, causing an oxygen deficient atmosphere. At approximately 9:00 a.m. on June 8, 2009, Employee #1 entered the black cocoa control room. A surveillance video of the area showed that within minutes of entering the control room, Employee #1 became unconscious. At approximately 10:00 a.m. on June 8, 2008, Employee #2 entered the control room and quickly became unconscious. Employee #2 remained unconscious for approximately one hour after entering the control room. For unknown reasons, Employee #2 became semiconscious and used a phone to report Employee #1 as deceased and report their location. A supervisor quickly called 911, and employees quickly responded to the black cocoa control room. The employees who responded were unaware of the asphyxiation hazard and briefly entered the black cocoa control room. The responding employees told Employee #2 to remain in the control room, while they left to meet the outside emergency responders. Meanwhile, Employee #2 left the control room. Employee #2 was eventually located in a nearby stairwell, semiconscious. Employee #3, who was one of the first employees to reach the accident scene, became winded from running up and down stairs and was prompted by the Fire Department to seek medical attention at the hospital. Employee #1 was pronounced dead at the hospital. Employees #2 and #3 were admitted to the hospital for observation.