46 CFR § 108.423 - Fire hydrants and associated equipment.
(a) A fire main system must have enough fire hydrants so that each accessible space may be sprayed with at least two spray patterns of water.
(b) In a main machinery space, except a shaft alley with no assigned space for stowage of combustibles, each spray pattern of water must be from one length of fire hose and each must be from a separate outlet. In all other spaces at least one spray pattern of water must be from one length of fire hose.
(c) No outlet on a fire hydrant may point above the horizontal.
(d) Each fire hydrant must have at least one spanner and at least one fire hose rack or reel.
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