Federal law requires that the following types of vessels carry one or more Type B, USCG–approved fire extinguishers:
- Vessels with an inboard or stern-drive gas engine(s)
- Vessels with closed compartments under seats where portable fuel tanks may be stored
- Vessels with double-bottoms that are not sealed to the hull or completely filled with flotation material
- Vessels with closed living spaces
- Vessels with closed storage compartments in which combustible or flammable materials may be stored
- Vessels with permanently installed fuel tanks (If a fuel tank is so heavy that persons on board cannot move it, the USCG considers it permanently installed.)
Approved types of fire extinguishers are identified by the following marking on the label—“Marine Type USCG Approved”—followed by the type and size symbols and the approval number.