Driver/ops Ch 7-11, 15 Flashcards
Minimum flow setting for interior structure firefighting?
95-100gpm
Formula for gpm out a solid stream nozzle
GPM= 29.7 x d(squared) x squareroot NP
Define master stream
Any fire stream that is too large to be controlled without mechanical aid
Four categories of master streams
Monitor, turret, deluge, elevated master stream.
How is a monitor different than deluge?
Stream direction and angle can be changed while water is flowing
What is turret pipe?
Mounted on apparatus deck, connected directly to the pump by direct piping
What is deluge set?
Short length of hose with s large nozzle supported by tripod.
Elevated master stream?
Large capacity nozzle at the end of an aerial device.
Nozzle reaction for solid stream nozzles formula
NR= 1.57 x D squared x NP
Nozzle reaction for fog streams formula
NR = .0505 x Q x squareroot nozzle pressure
Q= total flow in gpm
What causes friction loss?
Hose condition, couplings, kinks, volume of water flowing per minute.
Friction loss formula
FL= coefficient x gpm/100 squared x length/100
FL= CxQ2xL
Elevation pressure formula
EP= .5xheight
Two types of flow meters
Paddle wheel and spring probe
Classy fuels are divided into what two categories?
Hydrocarbons and polar solvents
Four methods foam may be proportioned
Induction, injection, batch mixing, premixing
What is class A foam?
Formulation of hydrocarbon surfactants that reduce the surface tension of the water in the foam solution.
Shelf life of protein based foams
Ten yrs
Shelf life of synthetic based foams
20-25 yrs
What is the most common type of foam used today
aFFF
Aqueous film forming foam
Tactical advantages of CAFS
Longer fire stream reach, durable uniform air bubbles, resists heat longer, hose lines weigh less, safer attack from greater distance.
Still lame
CAFS limitations
Expensive, erratic hose reaction, hose ruptures, additional training.
True false: nozzle flow rates should be different for class A foam application as for water.
FALSE
They should be the same. It’s safety
IFSTA definition of handling nozzle:
Any nozzle that one to three firefighters can safely handle and flows less than 350 gpm
4 techniques for applying foam
Direct application, roll on, bank down, rain down
What are Durable agents
Water absorbent polymers rather than hydrocarbon based surfactants.
When mixed with water they form minute polymer bubbles filled with water.