PART SIX: PLUMBING SYSTEMS WITH NOTES ON FIRE SUPPRESSION
TABLE 18-6. ABYC A-4, MINIMUM NUMBER OF REQUIRED HANDHELD
EXTINGUISHERS
Boats over 65 ft. (19.8 m)
Gross Tons* No.of Extinguishers USCG Type Location
Not over 50 1 † B-II Outside engine compartment
1 B-II Helmsman’s position
3 B-I Galley, crew’s quarters,
and cabin
50–100 1 † B-II Outside engine compartment
2 B-II Helmsman’s position and
galley
2 B-I Crew’s quarters and cabin
100–500 1 † B-II Outside engine compartment
3 B-II Helmsman’s position, galley,
and crew’s quarters
1 B-I Cabin
*Tons are admeasured gross tons, not displacement.
†Add an additional B-II extinguisher if over 1,000 hp is installed, and for each
additional increment of 1,000 hp.The minimum number is just that, a minimum. It’s a good idea to install 2 or 3 times the min-
imum number as a rule. A typical 44-foot (13.4 m) motor cruiser, for instance, might have an
extinguisher in or just outside the galley, in or just outside each stateroom, at or near the
helm, in or just outside the main saloon, and in or near the cockpit, as well as in or near the
engine compartment. This would be five or six extinguishers. Larger is better—up to B-II size—
if you can find the room.Fixed Fire Extinguishers
As we saw at the beginning of Chapter 4, handheld fire extinguishers are not up to putting out ma-
jor engine-compartment or fuel fires. For this reason, I recommend that all boats with engine
compartments install automatic, fixed fire extinguishers. These usually discharge either CO 2 or
FE-241. The manufacturer’s recommendation for capacity to serve the compartment’s volume
should be met or exceeded (see Table 18-7 for capacity/volume). (NOTE: Many references still
specify Halon. Halon has been banned to protect the ozone layer.)
An automatic extinguisher should be wired to automatically close the fire dampers, turn
off the engine blowers, and turn off the ignition. It should also sound a fire alarm. If a manu-
ally operated fixed fire extinguisher is installed without these automatic shutdowns, a warning
placard must be located near the fire-suppression controls stating that the engine and blowers
must be turned off before discharge. This is acceptable, but arranging these shutdowns as
automatic doesn’t cost that much more, and the crew will have enough on their minds in such a
situation. If toxic chemicals are used, there should also be a placard outside the machinery
space warning that the fire-suppression gases are toxic and indicating to use the blower to
clear all gas before entering.(Continued from previous)