All vessels are required to have a Type B fire extinguisher on board if one or more of the following conditions exist:
- Inboard engine
- Closed compartments where portable fuel tanks may be stored
- Double bottoms not sealed to the hull or which are not filled completely with flotation material
- Closed living spaces
- Closed storage compartments in which flammable or combustible materials may be stored
- Permanently installed fuel tanks (any tank where the removal of the tank is hampered by the installation of tie-down straps or clamps)
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.