Foam Flashcards
Class A and B foam that we use at TFD are High or Low expansion foams?
Low
What are class A foams used for?
Ordinary combustibles
What are class B foams used for?
Flammable liquids
What are the 5 class B foam types listed in the powerpoint?
Protein foam Fuoroprotein foam Film Forming Fluoroprotein foam (FFFP) Aqueous Film Forming Foam (AFFF) Micro-Blaze Out
Hydrocarbon fuels ____ on water and are ____. (Wont mix with water)
Float
Hydrophobic
What does hydrophobic mean?
Wont mix with water
What are 7 examples of hydrocarbon fuels?
Gasoline Kerosine Fuel oil Benzene Jet fuel Crude oil Naptha
Hydrocarbon fuel fires typically give off what color of smoke?
Black
Polar solvents are hydrophillic which means that…
They mix with water
What are 7 examples of polar solvents?
Alcohols Esters
Acetone Acids
Lacquer thinner Isopropyl
Ketones
Which burns cleaner, hydrocarbon fuels or polar solvents?
Polar solvents
Sometimes while polar solvents are on fire, the ___ is not visible
Flame
What are the 4 ways that foams work?
Smothering
Separating
Cooling
Suppressing
What is smothering?
Preventing air and flammable vapors from combining
What is separating?
Intervening between the fuel and the fire
What is cooling?
Water in the foam lowers the temperature of the fuel and adjacent surfaces
What is suppressing?
Preventing the release of flammable vapors
Many agents can extinguish a class B fire, however, foam provides what 4 things?
Firefighter safety
Prevention of fuel ignition/reignition
Suppression of flammable vapors
Post fire security
What is surface tension?
The ability of water to bind together
Does foam increase or decrease the surface tension of water?
Decrease
Decreasing the surface tension of water allows the foam to do what?
Float on top
What are the 3 types of incidents that may require foam?
Transportation accidents
Chemical spills
Spills of paint, motor oil, lacquer thinner (Flam. Liq. stored in warehouses and department stores)
What 3 things is foam NOT effective on?
Class C (electrical fires)
Pressurized gas
Combustible metals
What is the friction loss on a foam proportioner?
55 psi
What is foam “solution”?
The foam concentrate mixed with water
What is the foam tetrahedron?
Foam concentrate
Water
Air
Mechanical agitation
Foam is generated by what 3 things?
Mixing foam concentrate with water to make foam solution
Mechanical agitation
Aeration of the foam solution as it leaves the nozzle or is introduced before leaving the nozzle
Where does mechanical agitation occur?
As the water and foam concentrate pass through the hose
With finished foam, greater expansion = ____ ____
Slower drainage
As the foam drains it will become ____. It may look the same but will allow the ____ of ____.
This foam is called ____ ____
Dry
Release of vapors
Skeletal foam
What are the 3 foam application techniques?
Bounce off
Bank-in
Lofting/raindown
When applying foam to a fire, what should you never do?
Plunge
da toilet
TFD engines carry what kind and how much foam on engines?
10 gallons of AFFF (Class B)
20 gallons of Class A in tank
Class B foam is proportioned at ___% or ___% with a ___ foot max hose lay
3% or 6%
250 foot
Class A foam is proportioned between ___% to ___% with a ___ foot max hose lay
.1 to 1%
350 foot
The proportioner should be set at __ gpm
95 gpm
What stream should we use when applying foam according to TFD SOPs?
30 degree fog
What is the rate of application for a hydrocarbon fuel spill?
.10 gpm foam solution per square foot
What is the rate of application for an ignited hydrocarbon fuel spill?
.15 gpm foam solution per square foot
With un-ignited fuels, you may use a ____ percentage of solution per square foot to suppress vapors.
But you should make sure that in case of ignition…
Reduced
You should have enough
What is gasoline blending?
Blending a polar solvent with a hydrocarbon
This is a process performed at the refinery level
What are the results of gasoline blending?
A slightly polar hydrocarbon with high vapor pressure and a low surface tension
What are 2 products used in blending?
MTBE- Methyl Tertiary Butyl Ether
Methanol
What kind of foam must you use for gasoline blending and where can you find a supply of it?
AFFF/ARC
Station 1
What are 5 safety considerations with foam?
Identifying the hazard Preserving the blanket Wind direction Flowing fuel Backup lines
What are 3 ways we can preserve the foam blanket?
Do not apply water to the foam
Do not walk in the blanket
Do not drag hose in the foam blanket
The powerpoint lists 8 reasons why eductors fail, try to list them all.
Mis-matched eductor and nozzle Air leaks in pick up tube or hose connection Improper flushing after use Kinked discharge hose line Nozzle elevation Too much hose between eductor and nozzle Incorrect inlet pressure to eductor Partially closed nozzle
Departments throughout the nation are going to class __ foam
A
What are 4 safety benefits for class A foam?
Quicker knockdown (more tenable atmosphere)
Easier overhaul because of the absorption of water into the material
Use less water (less water damage)
Can be used for pre-treatment in wildland fires
What is one concern of class A foam?
Footing may be slippery
What is wet water?
Good for decreasing the surface tension of water
Does wet water foam?
NO
So there is no barrier
Still will work for deep seated fires
What is the ratio for wet water?
1 bottle for a 500 gallon tank
What is micro blaze out?
Non-toxic, biodegradeable penetrating agent containing non-pathogenic microbs that digest hydrocarbons
Micro blaze out is UL listed for ____ ____
Fighting fire
3 other things for Micro blaze out…
Still not being used to fight fire at this time
Saves us $ for spill clean up
Used for hydrocarbon spills
What is the ratio for Micro blaze out?
2.5 gallons of water for 8 oz of micro blaze out
What is high expansion foam?
Water combined with synthetic surfactant, detergent type foaming agent and anti-freeze
What is the expansion rate for high expansion foam?
200:1 to 1000:1
What is high expansion foam useful for?
Fighting class A fires in indoor structures and inaccessible places (done by totally flooding area)
What does high expansion foam do?
Displaces oxygen
What is one consideration when using high expansion foam?
Structure must be properly ventilated
Where is the only place that we can find high expansion foam generators?
At the PSA
WP-25 produces ___cfm when pumped at 200psi at the inlet
2500cfm
High expansion foam generators foam concentrate is ____ proportioned at the required rate and has an optional ____ ____ to direct foam through openings
Automatically
Discharge tube
