Abstract: At approximately 7:00 p.m. on September 23, 2013, Employee #1 and #2 were working at a chemical production facility. The production manager told a coworker to place an obsolete trigonox 5-gallon container into the waste room. The coworker poured the trigonox into a 55-gallon waste drum between 10:00 a.m. to 12:00 p.m. on that day. There were two waste drums (liquid and solid) in the waste area adjacent to the compounding room. The liquid waste drum contained left over liquid chemicals from a chemical batch that included methyl methacrylate, ethyl acrylic, and trigonox 101 (2,5-Dimethyl-2,5-di(tert-butylperoxy)hexane). Both methyl methacrylate and ethyl acrylic are flammable liquids. Around 7:00 p.m., the chemicals in the drum reacted and accelerated due to a catalyst in the drum. The runaway reaction overpressurized the drum, causing it to fail and rupture and ejecting drum lid. The drum lid struck the ceiling and hit a steam pipe, which resulted in a fire. The vapors of methyl methacrylate and ethyl acrylic are heavier than air, and travel down to the underground drain from the waste area into the compounding room. Employee #1 was working at the filling station under the hood in the compounding room. The fire from the underground drain melted chemical filled plastic tubs on racks in the filling station. The fire had grown bigger because there was more fuel (flammable chemicals) at the filling station. Employee #1 tried to get out of the compounding room as fast as he could after the fire. He suffered second-degree burns to his face and back of his head, and third-degree burns to his right shoulder, arm, and fingers. Employee #2 was in the compounding room to check Employee #1's work when fire happened. The fire caused the power to shut down to the exit door. Employee #2 could not get out of the room. Other employees outside the compounding room knew that he was inside the room, so they tried to push the door open. When Employee #3 saw a crack of light at the door, he pushed himself to door and got out of the room. Employee #3 suffered second-degree burns to his right arm, third-degree burns to his right ear, right side of face, and serious respiratory problems. Employee #2 was transported to one medical center, where he was hospitalized for two weeks. Employee #3 was transported to three different medical center, where he was hospitalized for seven weeks.