46 CFR 108.496: Semi-portable fire extinguishers.

(a) The frame or support of each semi-portable fire extinguisher required by Table 108.495(a), except a wheeled semi-portable extinguisher provided for a helicopter landing deck, must be welded or otherwise permanently attached to a bulkhead or deck.

(b) If the following semi-portable fire extinguishers have wheels, they must be securely stowed when not in use to prevent them from rolling out of control under heavy sea conditions:

(1) Each extinguisher required for a helicopter landing deck.

(2) Each extinguisher that is not required by Table 108.495(a).

(c) Semi-portable extinguishers must be fitted with suitable hoses and nozzles, or other practicable means, so that all areas of the space can be protected.