RedactedNarrative: Single vessel, a 33ft Formula, catching fire and sinking. 
  According to both, they were tied up at John's Pass Marina taking on fuel before leaving to cruise for the day. When they had finished, subject1 left the vessel to go pay. When he returned, they began to untie. Operator started the port engine with no issue. When he started the starboard engine, there was a loud bang, and the rear starboard hatch was blown into the water. When they looked, they noticed the fire. The marina manager told them all to get off and untied the vessel and shoved it away, due to the danger of there being a fire close to the marina fuel pumps. Subject2, who was sitting closest to the source of the fire, suffered burns on her feet and legs. Later, a doctor diagnosed the burns as 2nd degree, with possible 3rd degree burns on her right foot. 
  
  I inquired to the use of the blowers before starting the engine. Both stated the blowers were ran for at least 3 minutes before starting. 
  