Dave Gerr - Boat Mechanical Systems Handbook-How to Design, Install, and Recognize Proper Systems in Boats

craft of any type. When installing any fire

main, I follow the requirements of the CFR

for passenger vessels, with the exception

that—on fiberglass boats—I may use alu-

minum pipe instead of steel.

The fire pump must deliver a hose stream

that projects at least 25 feet (7.6 m) out of the

nozzle.

The fire pump can be driven off the main

engine. It must be capable of operation both

from a remote central fire station and from

the pump.

Fire hoses and nozzles must be left perma-

nently attached to the hydrant and ready for

immediate use, and the hose and fittings must

be Underwriters Laboratories (UL)–approved

lined fire hose and assemblies or its equiva-

lent, with fittings of brass, bronze, or stainless

that won’t corrode in the marine environment.

The fire stations and hydrants must be

arranged so that hoses from the various fire

stations will reach all parts of the boat.

For vessels carrying more than 49 pas-

sengers or over 65 feet (19.8 m), the hose and

piping must be 1^1 / 2 - inch (40 mm) minimum

diameter.

For vessels under 65 feet and carrying

49 passengers or less, the hose may be good-

quality garden hose, not less than^5 / 8 - inch

(16 mm) diameter.

Since—other than on a small passenger

vessel—you usually will install fire mains

only on boats well over 65 feet (19.8 m), you

can consider 1^1 / 2 - inch (40 mm) fire hose and

piping, and 50 gpm (189 lpm) at 60 psi

(414 kPa) as measured at the pump outlet

as the fire-main standard. If you are using

apair of pumps for combined fire-main

and bilge-system operation, they should both

be sized to meet these requirements. One

pump that meets these requirement is Ober-

dorfer’s N13HDM pump (Figure 18-7). These

pumps have 1^1 / 2 - inch (40 mm) ports and meet

the required capacity.

PART SIX: PLUMBING SYSTEMS WITH NOTES ON FIRE SUPPRESSION

Figure 18-6. Fire
station with
hydrant, hose, and
nozzle

TABLE 18-3. CFR FIRE-MAIN POWER-DRIVEN PUMP/CAPACITY REQUIREMENTS

Subchapter T Description Capacity and/or PSI

Vessels less than 100 GT Vessels over 65 ft. (19.8 m) 1 self-priming, power-driven

carrying 150 or less and vessels less than 65 ft. pump, 50 gpm, 60 psi

passengers or having carrying more than (189 lpm, 414 kPa) minimum

overnight accommodations 49 passengers on gauge at outlet of pump

for 49 or less

Ferry vessels not more than 1 self-priming, power-driven

65 ft. (19.8 m) carrying pump,10 gpm minimum;

not more than 49 passengers pressure unspecified

GT = gross tons

Figure 18-7. Pumps suitable for fire mains

(Courtesy Oberdorfer)