Abstract: Employee #1 was working in the fuse building preparing and threading the machines for the next day's production. He had prepared the machines by adding a lacquer coating for the fuse and acetone to keep the lacquer from hardening. Once this was accomplished, Employee #1 swept the floor and placed the sweepings into a box beneath the table. He then proceeded to wash his hands in a 5-gallon container of acetone with approximately 1 to 2 gallons inside. An unknown ignition source ignited the vapors from the lacquer and acetone, resulting in a fire and explosion. Both substances have a flash point of 0 degrees Fahrenheit. A secondary explosion occurred. It is believed that this explosion originated in the box of sweepings, which contained a mixture of black powder and sawdust. Prior to the initial explosion Employee #1 noticed a trail of fire coming across the floor. He jumped out the door as the explosion occurred. Employee #1 had little training in his 2 months of employment.