The short answer is, no engine? No fire extinguisher. But even that is not 100% complete (see #5 below.)
U.S. Coast Guard-approved, marine-type fire extinguishers are required on boats where a fire hazard could be expected from the engines or fuel system.
Fire extinguishers are required on boats when any of the following conditions exist:
- There are closed compartments and compartments under seats where portable fuel tanks may be stored.
- There are double bottoms not sealed to the hull or that are not completely filled with flotation materials.
- There are closed living spaces.
- There are closed stowage compartments, in which combustible or flammable materials are stored.
- There are permanently installed fuel tanks. (Fuel tanks secured so they cannot be moved in case of a fire or other emergency are considered permanently installed. Also, if the weight of a fuel tank is such that persons on board cannot move it, the U.S. Coast Guard may consider it permanently installed.)
The subtlety here is that a boat with an engine – but with a small enough portable fuel tank that it could be thrown overboard in an emergency – is not required to have a fire extinguisher aboard.
But you’ll surely wish you had one aboard!