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FIRE AND FIRE FIGHTING
Fire is a constant threat aboard ship.
Personnel must take all possible measures to
prevent a fire or, if one is started, to extinguish
it quickly. Fires have several causes: spontaneous
combustion, carelessness, hits by enemy shells, or
a collision. If the fire is not controlled quickly,
it could cause more damage than the initial
casualty and could cause the loss of the ship.
Fighting fires is primarily handled by repair
parties. However, you must learn all you can
about fire fighting so that you will know what to
do if called upon.
Fires are classified into four types based on
the type of material burning and the fire-fighting
agents and methods required to extinguish the fire:
1. Class A fires involve solid materials that
leave an ash, such as wood, cloth, and paper.
Water is the primary means of extinguishing class
A fires. Carbon dioxide (C02) may be used on
small fires, but not on explosives. The flames of
a large fire usually must first be knocked down
(cooled) with fog. The material, particularly
mattresses and similar articles, is then broken up
with a solid stream for further cooling.
2. Class B fires involve flammable liquids
such as oil, gasoline, and paint. The best
extinguishing agent for class B fires is aqueous
film forming foam (AFFF). Another good
extinguishing agent is Halon. Halon systems are
being installed for combating class B and C fires.
For small fires, or in a confined space like a paint
locker, CO2 is a good extinguisher. For large fires,
other agents such as a water fog or foam must
be used. A solid water stream should NEVER be
used on a class B fire. The stream will simply
penetrate the flammable liquid’s surface, with no
cooling effect, and scatter the liquid, thus
spreading the fire.
Class B fires involve the three temperature
levels of flash point, fire point, and ignition point.
A small spark may be all that is needed for
ignition. Fire will flash across a surface, but will
not continue to burn; however, the flash may be
hot enough to ignite some other material or to
injure personnel.
3. Class C fires are those associated with
electrical or electronic equipment. The primary
extinguishing agent is CO2, but high-velocity fog
may be used as a last resort. Foam should not be
used as it will damage the equipment and may
present a shock hazard. A solid water stream
should NEVER be used. If at all possible, electri-
cal power to the equipment should be secured.
4. Class D fires involve metals, such as
magnesium, sodium, and titanium. These metals
are used in the manufacture of certain parts of
aircraft, missiles, electronic components, and
other equipment. A typical example is the
magnesium aircraft parachute flare. This flare
burns at a temperature above 4000°F with a
brilliancy of 2 million candlepower. Since water
coming in contact with burning magnesium
produces highly explosive hydrogen gas, a solid
water stream should NEVER be used on this type
of fire. However, low-velocity fog can put out the
fire in a matter of seconds with little danger.
Jettisoning the burning object overboard is
another method.
Despite the most carefully observed safety
precautions, a fire may still occur. If you discover
a fire, report it immediately so that fire-fighting
operations can be started. The efforts of even one
person may contain the fire until the arrival of
the fire party. If the fire threatens to get out of
control, try to prevent it from spreading. Secure
all doors, hatches, and other openings in the fire
area, including ventilation ducts, to confine the
fire within a specific boundary. You can establish
a primary fire boundary by cooling all bulkheads,
decks, and overheads surrounding the fire area.
Always ensure dewatering equipment (pumps) is
ready for immediate use in case of a fire. The
amount of water used for fighting the fire and
for cooling purposes may cause a serious ship
stability problem.
PREVENTIVE DAMAGE CONTROL
Naval ships are designed to resist accidental
and battle damage. Damage-resistant features
include structural strength, watertight compart-
mentation, stability, and buoyancy. Maintaining
these features and a high state of material and
personnel readiness before damage does more to
save the ship than any measures taken after
damage. Ninety percent of the damage control
needed to save a ship takes place before damage
and only 10 percent after the damage.
The division damage control petty officer
(DCPO) is one person in the DC organization who
helps to ensure that preventive damage control
measures have been taken. The DCPO oversees
the maintenance of divisional DC equipment and
also assists in training divisional personnel in DC.
Always keep in mind that damage control is
an all-hands evolution. The best way to defend
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