Abstract: At approximately 11:30 a.m. on December 21, 1997, Employee #1, a 20-year-old volunteer firefighter, was atop a burning 70 ft tall by 20 ft diameter silo, hosing water onto the flames inside. He apparently believed that the fire had been extinguished when coworkers removed a bottom panel from the silo to allow some of the 10,000 gallons of water dispensed on the blaze to drain. When the panel was removed, the resulting back draft caused an explosion. Employee #1 was trapped on top of the silo by the cyclone for approximately two hours. He sustained contusions to his chest and back, for which he was hospitalized.