Abstract: On July 2, 2011, two employees of Dredge and Marine Company, LLC were fabricating a new dredge boat at the John W. McDougal Company facility in Nashville, Tennessee. The primary reason for the work was to paint the interior compartments of the pontoons that serve as floatation and fuel storage for the dredge. After some employees cleaned the pontoon compartment with a shop vacuum, Employee #1, a painter, entered the compartment (5 feet tall by 6 feet wide by 10 feet long) through a 24-inch manhole on the pontoon top. Employee #1 was wearing a supplied-air hood which was connected to an air compressor located outside the compartment on the concrete floor. Employee #1 also took with him inside the compartment the paint spray gun, which was connected to an airless sprayer located outside the compartment on the concrete floor. A light was placed inside the compartment, which provided light for the painting operation after it was plugged into an electrical outlet via an extension cord. A 5-gallon bucket of paint was placed under the airless sprayer. The paint used was the Warren Paint and Color Company's 2700, Number 16 Metalcoat Gray Primer, containing 19.3 percent xylene and 15.4 percent VMP Naptha, according to the MSDS. Spray painting inside the first pontoon compartment, which was on the forward, starboard side (front-right) began around 8:00 a.m. Employee #2 was designated as hole watch for the painter. Employee #2, the hole watch, was stationed on top of the pontoon near the manhole, and maintained visible contact with the painter, and ensured the air line and paint line hoses maintained the proper slack. Around 9:00 a.m. the painter was nearing completion of painting this compartment when a spark ignited the paint vapors inside the space. A loud explosion and blue flames, reportedly 20 feet high, which lasted 10 to 15 seconds, were coming out of the manhole where Employee #1 was working. Employee #1 climbed out of the pontoon compartment and the other workers began assisting him. Employee #1 died in the hospital on July 5, 2011. Employee #2's face, arms, chest, and back were burned by the flames and he was hospitalized.