Abstract: At approximately 6:02 p.m. on May 16, 2002, Employee #1, who had finished work for the day and was leaving the parking lot when he turned his truck around and raced back to the facility. Employee #1 got out of his vehicle and ran up an outside stairway yelling that there was a fire in the Bag House, which sits atop the portion of the Bagging Bin located above the plant's 30 ft roof. Employee #1 was on his way to the shift supervisor's office on the second floor mezzanine located above line Number 2's flash dryer to warn the line Number 2 operators of the problem since they could not see the fire. The operators inside the supervisor's office saw Employee #1 pointing and shouting fire on the roof when an explosion occurred. Examination of the equipment in the bagging station area inside the 56,000 square foot plant's building indicated that an ignition of the finely ground rubber dust product being manufactured had occurred inside the bagging bin which was the only piece of process equipment to display signs of an over-pressure. The bagging bin and the reversible screw conveyor underneath suffered a mechanical failure. This mechanical failure allowed pressure waves and hot gases to exit the bagging bin. At this point the fire progression inside the production area followed the dispersion of fugitive dusts which were becoming airborne by the preceding pressure waves. Once started, the fire quickly spread through the plant. Used cans of foam insulation were found that were used by maintenance personnel to seal leaks. Rust holes around a product conveying pipe were found. It is believed that rubber dust which had previously been expelled from the line Number 2 dryer system's exhaust stack had been deposited atop the bagging bin. Workers routinely cleaned dust from the roof but had been stopped of the practice of using compressed air. A fire had been experienced inside the Line Number 2 Dryer system's duct work between 4:00 and 4:30 p.m.. Hot embers are believed to have settled on the existing layer of dust described above. Due to the negative pressure created inside the top of the bagging bin by the bag house blower-vacuum system, the hot smoldering embers were sucked into the bagging bin causing the violent dust deflagration. Employee's #1, 2, 3, 4, and 5 were hospitalized with burns but eventually died. Employee's #6, 7, 8, 9, 10, and 11 were hospitalized with burns and Employee #12 received burns but was not hospitalized.