CAFS Flashcards
the ratio of the foam’s volume in its aerated state as
compared to the original volume of the non-aerated
solution is called the _______.
expansion ratio (gallons solution:gallons finished foam)
Low-X expansion ratio is between:
1:1 to 20:1
Mid-X expansion ratio is between:
21:1 to 200:1
Hi-X expansion ratio is between:
201:1 to 1000:1
the time it takes for foam bubbles to pop is called?
drain time
the higher the expansion ratio, the ______ the
drain time.
longer
the dryer the foam, the ______ the drain time.
longer
the minimum rate at which a foam solution or finished
foam can be applied to a given fire in order to achieve
extinguishment is called the ______.
critical application rate
3 parts to a CAFS
air compressor
water pump
foam injector
3 types of air compressors
1) reciprocating piston
2) rotary vane
3) rotary screw
nozzles that introduce air into a foam solution by the
Venturi Principle are called ______.
aspirating nozzles
the rapid pressurization of a structure caused by an
increased heat absorbtion which causes a rapid steam
expansion and penetration and can aid in exterior
firefighting is called ______.
compressed air foam push
foam solution that has been aerated is called ____.
finished foam
finished foam that is produced when metered at a
1:1 ratio. this foam type is recommended for _____
because it will stick to vertical surfaces and typically
has a longer drain time. it resembles _____ and is
called ______.
exposure protection
shaving cream
fluid foam
device that allows foam concentrate and water to mix
is called a _____.
foam proportioner
mixture of foam concentrate and water is called ____.
foam solution
4 components of the Foam Tetrahedron
1) water
2) foam
3) air
4) agitation
foam generating systems that includes the energy of
an air compressor to the energy of a water pump are
called _____.
high energy systems
foam generating systems that uses the velocity of a
a water stream to mix air with the solution at the nozzle
tip to deliver finished foam are called ______.
low energy systems
NAFS
nozzle aspirated foam system
CAFS
compressed air foam system
rotary screw air compressors are capable of achieving
output pressures over _____ psi and output volumes
over _____ cfm.
200
1500
a dangerous condition in CAFS when the foam solution
is not rich enough or unevenly mixes with air and causes
pockets(______) of water and air to the nozzle. this is
called _____.
slugs
slug flow
_____ lower the surface tension of a liquid.
surfactants
a method of foam application for exposure protection
using a 2-layered foam blanket. wet foam is applied
first and then followed by a layer of fluid foam. this
provides a stronger insulation against radiant heat or
direct flame contact. this is called
2-tier exposure protection
as water flows through a constricted pipe, velocity
increases and pressure is reduced allowing foam
concentrates to be introduced to the water supply.
the principle behind this is called _____.
the venturi effect
“very wet foam” has a ratio of _____?
it is recommended for _____.
3:1 (water:air)
master stream operations
“wet foam” has a ratio of _____? and is recommended
for most applications on ______ fires. it resembles ___.
2:1 (water:air)
Class A
ice cream
