Abstract: On February 8, 1996, Employees #1 through #4 were performing their normal duties. Employee #1 was the mill manager. Employee #2's truck was being loaded with grain, and Employee #3 was delivering raw grain. These three employees were on the ground floor of the south mill. Employee #4, an operator, was in the personnel elevator between the third and fourth floor. At 6:18 p.m., an explosion occurred on the second floor of the south mill. The ignition source was not identified, but the explosion was apparently caused by ignited material from an improperly installed and maintained #6 fuel oil boiler smoke stack. The ignited material traveled through the south mill grain-receiving bay with the wind, igniting suspended-in-air combustible grain dust. The fireball entered the south mill at or near the #1 cooler on the second floor. Employees were hospitalized with burns.