Abstract: At 6:38 a.m. on December 3, 1987, Employee #5 set off an alarm on press 92 for the fixed extinguishing system in a press room. The area was evacuated and Employee #5 informed the fire chief that it was a false alarm. Employee #4 opened the overhead door to the press room on the southeast side to ventilate the area because the manual shut off valve on the carbon dioxide tank was malfunctioning. The carbon dioxide emptied on press 91, which set off the alarm without anyone knowing before the overhead door was opened. The carbon dioxide spread into the fire brigade room, which is across the hall from the open door. Members of the fire brigade were overcome and transported to the hospital. Thirteen of the fifteen employees were admitted and treated for hypoxia.