I don't know jack about boats.... I'm assuming a "blower" is something to purge the fuel lines or pressurize the system so you know it's not leaking?
I hope no one was hurt in the fire.
Before you start your boat that has an inboard motor (and I do this as well after I shut the motor off), you turn the blower fan on to disperse any gas fumes from the engine compartment. No one was hurt fortunately.
Glad no one was hurt. Was it the 1st use of the season?
I remember raising up the engine covers and hatch covers as well as the generator compartment every time before we used the houseboat. Sure it had a blower as well but gas leaks or issues are better if detected before even turning the blowers on.