RedactedNarrative: Operator and his girlfriend Witness 1 were launching their boat at Craig's Creek Boat Ramp on      8-14-2021. Operator was in the boat while Witness 1 backed the boat into the water. Sgt. 1, Officer 2, Officer 3 and I were tied off to the courtesy dock at the time of the incident. We heard and saw the engine compartment explode on Operator's boat. Operator jumped out of the boat and into the water. 
   
  Sgt. 1, Officer 2, Officer 3, and I ran over to help. Sgt. 1 had brought the fire extinguisher from our boat. Sgt. 1 passed the fire extinguisher to Operator while he was in the water. Operator was able to use a fire extinguisher for a minute to help put out the fire until he realized how much pain he was in. Sgt. 1, Officer 2 and I used four fire extinguishers to put out the fire. The fire had grown significantly in the time it took us to retrieve our fire extinguishers. Sgt. 1, Officer 2 and I were able to completely put out the fire and then helped with treatment of Operator.  Officer 3 and Witness 2 (Off Duty Nurse) helped treat his burns. Witness 2 advised us to soak rags with cool water to place them on Operator's burns. Officer 2 retrieved some towels from his patrol truck and soaked them to place on Operator's burns. Officer 2, Officer 3, and I helped soak and hold wet towels on Operator’s burns while Sgt. 1 notified EMS. 
   
  Gallatin County EMS arrived on scene and transported Operator to a nearby landing zone to fly him to University of Cincinnati Hospital to treat his wounds. 
   
  Owner showed up on scene while EMS was treating Operator. Owner is co-owner of the boat. 
   
  Officer 4 and Officer 5 interviewed Operator at the University of Cincinnati Hospital. Operator stated he had tried launching the boat earlier in the day but had to leave to replace the fuel line. They had fueled the boat on their way back to Craig's Creek after replacing the fuel line. Operator stated he did not run the blower to ventilate the engine compartment before starting the engine. Also, this was his first day on the water in this boat. 
   
  Operator received burns on his head, arms, legs, and neck. Operator's boat sustained burn damage to the passenger compartment and engine compartment.