6-17. PKP EXTINGUISHERS. Potassium bicarbonate (PKP) is carried in 10-pound portable extinguishers on board the
LSV. When fighting a surface fire, aim the discharge at the base of the flames and apply in a rapid, side-to-side,
sweeping motion, gradually progressing toward the base of the fire. PKP discharge causes a clouding effect which will
reduce visibility and will render breathing difficult. Small Class B fires can be quickly extinguished by PKP fire
extinguishers but, unless the ignition source or fuel is removed, flame flash-back could be experienced. A backup fire
hose with low-velocity fog applicator should always be made available as quickly as possible. PKP can be used
simultaneously with water.
A PKP fire extinguisher should not be laid on its side when in use. This will cause the gas
expellant to be released and not the potassium bicarbonate.
If the fire persists after expending two PKP extinguishers with little or no effect, low-velocity fog should be used.
Low-velocity water fog is superior to PKP on Class A and Class B fires.
6-18. AFFF. Aqueous Film Forming Foam (AFFF) is carried in 2-1/2 gallon, 28-pound portable extinguishers. When
fighting flammable liquid fires, aim the discharge at the base of the flame and apply it in a slow, steady side-to-side
sweeping motion so that the liquid overruns the fire surfaces, establishing and maintaining the film that smothers the fire.
After the film is established, do not break it by splashing the stream on the film surface. In the case of a Class A fire, the
stream should be pointed directly at the source of the flames to penetrate and cool the fuel.
Section IX. BASICS OF FIGHTING FIRE
6-19. GENERAL. While fire fighting techniques cannot be set forth in any chronological pattern, the following basic
rules apply to nearly all situations:
a. Isolate the fire. Close all doors, hatches and vents, and secure blowers. All flammable liquid system piping in
the affected area should be isolated from damage control deck.
b. Shut down electrical circuits in the compartment where the fire is located and in adjacent spaces to be sprayed or
c. Bring required fire fighting equipment to the scene.
d. Lead out two hoses from different plugs, when practical, to the area of the fire; rig one hose with an applicator,
and charge both hoses.