| Tweet |
Custom Search
|
|
|
||
 TM 55-1905-223-SDC
(14) Electrical circuits and ventilation systems tested.
(15) Amount of damage done.
(16) Electrical power restored or isolated.
_________
WARNING
Crew members without OBAs will not enter a compartment
prior to the compartment being tested as safe to enter.
Serious personal injury to crew members could result.
q. If C02 is directed into a fire so that sufficient oxygen to support combustion is no longer available,
the flames will subside. Depending on the fuel, this action will take place when the normal 21 percent oxygen
in the air is diluted with C02 to 15 percent oxygen or less. Some Class A fuels require that it be reduced to
less than 6 percent oxygen in order to extinguish glowing embers. The smothering action of C02 gas is
temporary, however, and the firefighter must remember that the fire will quickly rekindle if the oxygen is
supplied again in the presence of an ignition source. The temperature of the burning substance and its
surroundings must be lowered below its ignition temperature if the fire is to remain extinguished.
A compartment is dangerous and hazardous to life when it is filled with C02 due to the lack of oxygen; it shall
not be entered unless the party is wearing OBA. In the use of small portable C02 extinguishers, the quantity of
gas released from one or several of these cylinders is not usually sufficient to reduce the total oxygen content
of the air in a compartment to a dangerous minimum. Therefore, the firefighter has basically to consider only
the speed with which he can apply C02 from these to the fire.
If C02 is applied quickly, the fire will go out immediately. It should be applied to the base of the fire, in a
sweeping motion. In continuous operation, the 15-pound cylinder will be expended in about 40 seconds. A
discharged cylinder must be turned in to the designated area for recharging.
While C02 extinguishers are designed for hand application, they can be used in a small compartment as a
compartment with their valves open. With the doors and ventilation secured, the C02 will settle and form a
blanket over the lower portion of the compartment. One 15-pound cylinder will cover the bottom of an 11-foot
by 12-foot compartment to a depth of approximately 1 foot.
Section X. LCU FIRE MAIN
6-20. GENERAL. The fire main system (FIGURE 6-5) is made up of two electrically driven pumps and
one diesel driven pump.
a. Fire pumps. The two electric fire pumps, located in the machinery space just forward of the
starboard main diesel, are rated at 250 GPM with a discharge head of 125 psi. The auxiliary fire pump is
located in the bow thruster room and is driven by the bowthruster diesel engine. It is rated
|
||
|
||
