Lesson Plan 11 Foam Flashcards
There are two basic types of foam;
Chemical foam and mechanical foam
The two basic ingredients of foam are ____ and _____
gas / liquid
The types of mechanical foams inlcude:
Protein/Flouroprotein
Synthetic Detergent
AFFF (Aqueous Film Forming Foam)
Mechanical foam is formed by mixing _____ and a liquid ______ agent with a ____, which is typically ____.
water; foaming; gas; air
In all foams, the bubble functions as a vehicle to _____ ____ to the fire.
carry water
Foam has proven to be the ____ _____ means of controlling and extinguishing fires for most _____ _____ (Class _), and is used successfully on ____ _ materials where penetration of water into deep-seated fires is important.
most effective; flammable liquids/Class B; Class A
____ is the gaseous agent in modern foams, and ____ is the main ingredient (____ to ____) of each bubble’s wall.
Air; water; 95%-99%
The remaining 1% to 5% of the bubble’s wall is made up of ____ ____
foaming agent
Foams can control and extinguish flammable liquid in a variety of ways, name the 5 listed:
- Exclude O2 from flammable vapors, smothering the flames
- Cool the fuel surface with the water
- Content of the foam (which relates to chemical foam containing CO2
- Prevent release of flammable vapors from the fuel surface
- Chemically absorb the heat created
The 3 components of firefighting foam _____, ____ _____, and ____ are combined using a ________ that meters a prescribed amount of foam concentrate in to the water flow and a nozzle (_____ ____) with an air inlet (_____) or mechanical agitator (______ _____). The water and foam liquid solution mixed at the proportioner passes on to the foam nozzle which introduces ____ into the mixture to generate foam.
water; foam concentrate; air; proportioner; foam generator; aspirating; spinning teeth; air
4 methods of proportioning are
Induction
Injection
Batch mixing
Premixing
Class A foam concentrates are used primarily for controlling or preventing fires involving _____ ______; acting as a _____, reducing the _____ _____ of the water which allows the water to easily penetrate the burning material. The foam properties allow for a blanket of foam to be created to protect ______ areas or prevent ______.
ordinary combustibles; surfactant; surface tension; unburned; re-ignition
Class A foam may also be used as a _______ agent for Class B _____ (_____) flammable liquid spills especially when the spill/fire involves Class A materials.
smothering; hydrocarbon / non-polar
Class A foam should not be routinely used on fuel spills deeper than ___ and should never be mixed with ______ foams.
1/2” ; AFFF
Class A foam is _____, ____ and _____, making it a first choice for firefighting operations.
non-corrosive; non-toxic; biodegradable
Using Class A foam makes water up to ____ ____ more effective on Class A fires.
5 times
Proportioned rates for Class A foams vary from ____ to ____. In the COB we use ____ as our default for structural firefighting. ____ to ____ is used for wildland or grass fires. ___ to ___ may be used to create a thick foam blanket to stop flame spread or smother a fuel/spill fire.
0.1% - 1.0%; 0.1%; 0.3% - 0.5%; 0.5% - 1.0%
T/F - AFFF foams are not environment friendly
T
AFFF is the standard product in situations where hydrocarbon fuels are the major risk. What are the 4 advantages
- Excellent fire performance
- Use in a wide variety of equipment
- Long storage life
- The AFFF/ATC concentrates are used on a wide range of polar and nonpolar flammable liquids and may be used on ordinary combustibles
Effectiveness of AFFF stems from its ability to cause a ____ ____ of water solution to float on top of ____ ______ liquids. When applied, they not only form a foam blanket, but they also develop an _____ _____ that drains from the foam and forms a ____ ___ which restricts the emission of flammable vapors.
thin film; non-polar flammable; aqueous film; vapor seal
T/F AFFF is dependent upon foam expansion (air entrapment) for its fire extinguishing effeciency
False - provides the aqueous film as well
Protein/fluoroprotein and synthetic foams attack the fire tetrahedron from ____ sides. The foam blanket ______ _____. Water in the bubble takes away ____. Until a complete foam blanket is established, no effective _____ _____ of the fuel can take place.
2; excludes O2; heat; vapor sealing
AFFF and AFFF/ATC foams, in contrast from Protein/Synthetic foams, perform all ____ functions of the fire triangle. The foam blanket _____ ____. Water in the bubbles takes away ____ and the _____ ____ slows vaporization, thus cutting off the _____ of the ____ to the fire.
3; excludes O2; heat; aqueous film; supply; fuel
Novacool is a _____ ____ ___ (___) that uses a chemical reaction along with the benefits of foam to extinguish and control the fire by cooling. It can be used on ______, ____, and ___ fires.
Universal Extinguishing Agent (UEA); Class A / B / D
How fast can Novacool take for the energy transfer from fire to water via the photochemical reaction
.001 up to .000001 of a second that 10 to the negative 3 to 10 to the negative 6 power
Using our in line eductors; what are the nozzles set at for proper gpm and nozzle pressure. What is the maximum hose length from the eductor and pressure at the eductor.
95 gpm or 125 gpm with a nozzle pressure of 100 psi. Max distance from the eductor is 150’ with a pressure at the eductor at 200 psi
Proportioning devices (inline eductors) are designed to meter the AFFF at the proper concentrations (____, ____, or ___) in the water stream
1%, 3%, 6%
Eductors use the ______ principle to pull the foam concentrate into the water stream
venturi
What prevents water from flowing back into the pickup tube and concentration container of an inline eductor.
ball check valve
Eductors operate on _____ ____, the water volume through an area, not ____ ____
water flow; water pressure
Generally, _____% or more on the inlet pressure is lost in the _____. For this reason, most eductor manufacturers recommend a minimum inlet pressure of _____ psi
40%; eductor; 200
Most BFD apparatus are equipped with on-board foam proportioning systems. These are ____ ______ - _____ ____ - _____ _____ systems. This system can provide a foam solution in ratios from _____ to ____%
variable flow - variable rate - direct injection systems; 0.1% - 3%
Novacool is used at a rate of ____%
0.4%
When approaching a hazard requiring foam, the firefighter must determine 3 specific questions
What is the hazard (fire or non-ignited spill)
What is the fuel (polar i.e. ethanol or non-polar ie gasoline)
What is the area of the hazard (ft/2)
With gasoline fires (non-polar) Novacool should be used for initial attack at _____ %
0.4%
For ethanol or polar fires, Novacool should be used at ____%
1%
Emergencies involving spills (non-ignited) spill control is conducted in 4 separate steps:
Identification
Containment
Control
Removal
Fire in ordinary combustible materials, such as wood, cloth, paper, rubber and many plastics
Class A fires
Fires in flammable liquids, oils, greases, tars, oil based paints, lacquers, and flammable gases
Class B fires
Fires which involve energized electrical equipment where the electrical non-conductivity of the extinguished media is of importance.
Class C fires
Fires in combustible metals, such as magnesium, titanium, zirconium, sodium, lithium, and potassium
Class D fires
Novacool definition: A UEF (______ _____ ____) for use in initial attack on Class __, ___ and __ fires, most often used at ____% except on alcohol type fuels where it is used at ____%
Universal Extinguishing Agent; A/B/D fires; 0.4%; 1.0%
