T&T: Federal Law re Using Blower Before Starting Engine

[John Buckwalter]

"But for those with a blower blowing in, and engine room
odors are getting into the rest of the boat, the direction
of air should be reversed. "

"Blowing air into the engine room can build up positive
pressure in the engine room, forcing the air in the engine
room out into the rest of the boat."

I don't know about your boat but my turbochargers suck more air that my 
engine room blowers provide.  In fact it is important for proper 
operation to have enough combustion air.  You better think twice about 
making the engine room more negative.

John Buckwalter