Abstract: At approximately 1:30 p.m. on February 1, 2017, an employee went into a tank that contained alkyl ketone to clean the tank. Witnesses stated the employee was inside the tank for approximately 10 to 15 minutes. A coworker cleaning a tank in Bay 3, in the same building, became concerned when he did not hear any activity in the next bay and as a result checked on the employee in Bay 4. The employee was found unresponsive face-up inside the tank with a full face respirator on. Emergency services were contacted. The employee had no pulse when retrieved from the tank and was transported to Liberty Hospital via EMS. The employee was killed. The tank had originally contained 1-(4-Chlorophenyl)-4, 4-Dimethyl-3-Pentanone, which is known as an environmental hazardous substance.