The measurements of pressure, including atmospheric pressure. measured in PSI absolute
Automatic/Constant Pressure Nozzle
nozzle with a spring mechanism built in that reacts to pressure changes and adjusts the flow and resultant reach of the nozzle
amount of water that can be moves to extinguish the fire, depends on the water supply, pump(s) and their capabilities, and the size and length of the hose.
a device used to fight fire in basements or cellars when firefighters cannot make a direct attack on the fire; has 6 or 9 solid tips or broken stream openings designed to rotate in a circular spray pattern
Combination Fire Attack
a blend of the direct and indirect fire attack methods, with firefighters applying water to both the fuel and the atmosphere of the room
spray nozzle that is capable of providing straight stream and spray patterns, which are adjustable or variable by the operator. most commonly used nozzle
Constant/Set Volume Nozzle
nozzle with one set volume at a set pressure. forexample, 60 gpm at 100psi - the only adjustment is pattern
Direct Fire Attack
an attack on the fire made by aiming the flow of water directly at the material on fire (directly at the seat)
Total amount of water flowing from the discharge side of the pump
the water or other agent as it leaves the hose and nozzle toward its objective, usually the fire
the rate or quantity of water delivered, usually measured in gpm or lpm (1gmp=3.785lpm)
delivers either a fixed spray pattern of variable combination of straight stream and spray patterns
caused by the rubbing of materials against each other while in movement and converts or robs some of the movement energy into heat energy
measurement of friction in a system such as hoseline
measures pressure without atmospheric pressure. measured in PSI or PSIG
measures the pressure of a column of water in feet. gain or loss results when water is being pumped above or below the lvl of the pump. a head of 2.31 ft = 1 psi
the study of fluids at rests and in motion
Indirect Fire Attack
an attack made on interior fires by applying a fog stream into a closed room or compartment, thus converting the water into steam to extinguish the fire
estimate of the amount of water required to extinguish a fire in a certain time period. based on the type and amount of fuel burning
a tapered or constricted tube used to increase the speed or change the direction of water or other fluids
the amount of volume of water that a nozzle will provide. measured in gpm or lpm
the pressure required to effectively operate a nozzle. always measured in PSI or kilopascals
the distance the water will travel after leaving the nozzle.
the force that makes the nozzle move in the opposite direction of the water flow.
originally designed to penetrate the skin of aircraft and now has been modified to pierce through building walls and floors
generic term to describe the person responsible for operating a fire apparatus pump.
Solid Stream Nozzles
type of nozzle that delivers an unbroken or solid stream of water to the fire. AKA solid tip, straight bore, or smooth bore
nozzle pattern that creates a hollow stream, similar in shape to solid stream pattern, but the straight stream pattern must pass around the baffle of the nozzle.
the arrangement or configuration of the water or other agent droplets as they leave the nozzle
Vacuum (Negative) Pressure
the measurement of the pressure less than atmospheric pressure, which is usually read in inches of mercury (in. Hg or mm Hg) on a compound gauge
Variable, Adjustable, or Selectable Gallonage Nozzle
nozzle that allows the nozzleperson to select the flow, with usually 2 or 3 choices, and the pattern
The forward pressure of water as it leaves an opening
Water Curtain Nozzle
designed to spray water to protect exposures against heat by wetting the exposure's surface
4 Elements That Affect Fire Stream
when water leaving the nozzle starts to fall over and break apart
Handlines use tips from ___ to ___ inches at ___ PSI.
3/4 to 1 1/4 inches at 50 PSI
Masterstreams use tips sizes of ___ inches and larger at ___ PSI
1 1/4 inches at 80 PSI
Why are small lines popular to use?
ease of mobility
number of personnel required to operate
their ability to extinguish one to three typical rooms of fire with their flow
The method of stream application or fire attack depends on what?
the fire's fuel
the fire's location
suppression equipment of the FD
When should you never use an indirect fire attack?
when there is a possibility of people in the room
1 cubic foot of water = ____ cubic feet of steam at 212F
Effective fire streams will these noticeable results when applied to a fire.
fire location becomes tenable
What is the equation for engine pressure (also called pump discharge pressure)?
engine pressure = nozzle pressure + friction loss +/- elevation + special appliances
Nozzle pressure for smooth bore handline
50 PSI (345 kPa)
nozzle pressure for fog handline
normal:100 PSI (690kPa)
mid: 75 (517 kPa)
low: 50 (345 kPa)
nozzle pressure for smooth bore master stream
80 PSI (552 kPa)
nozzle pressure for fog master stream
100 PSI (690 kPa)
What is the equation for nozzle reaction on a smooth bore nozzle?
Nozzle reaction = 1.57 x diameter of nozzle tip in inches, squared x nozzle pressure
What is the equation for nozzle reaction on a fog nozzle?
NR=gpm X the square root of nozzle pressure X .0505
What is the equation for friction loss?
FL = Q2 x C x L
Friction loss = quantity of water in hundreds of gallons per minute X friction loss coefficient for the diameter of the hose X length of the hose is hundreds of feet
Coefficient Value for 1 1/2 inch hose
Coefficient Value for 1 3/4 inch hose
Coefficient Value for 2 inch hose
Coefficient Value for 2 1/2 inch hose
Coefficient Value for 3 inch hose with 2 1/2 inch couplings
Coefficient Value for 4 inch hose
Coefficient Value for 5 inch hose
Coefficient Value for 6 inch hose
What is normally the cause of ineffective fire streams?
improper pump or nozzle operations
Elevation is usually rounded to ___ PSI per foot or ___ PSI per floor or 10 feet for practical fireground purposes.