Abstract: TWO EMPLOYEES WERE OPERATING A DISTILLER FOR REFINING USED ACETONE. THE DISTILLATION APPARATUS WAS LOCATED IN A BUILDING SEPARATE FROM THE MAIN MANUFACTURING FACILITY. FUMES FROM THE DISTILLATION PROCESS THAT HAD ACCUMULATED 6 TO 8 INCHES ABOVE THE SLUDGE BUCKET OF THE APPARATUS HAD SETTLED NEAR THE FLOOR. THESE FUMES WERE IGNITED BY AN ELECTRIC ARC FROM A CIRCUIT BREAKER. ONE OF THE EMPLOYEES, WHO WAS STANDING IN A DOORWAY, WAS KNOCKED OUTSIDE. THE OTHER EMPLOYEE WAS STANDING BEHIND THE CONTROL BOX FOR THE DISTILLER. BOTH EMPLOYEES RECEIVED BURNS ON THEIR HANDS AS A RESULT OF THE EXPLOSION AND WERE HOSPITALIZED FOR THEIR INJURIES.