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.