Pump Ops Chpt 6 Flashcards
The fire service operates three types of nozzles to produce three basic fire streams: _____,_______, and _____.
Solid, fog, and broken steams
A ________ is produced with a fixed orifice and a smooth bore nozzle. The stream is tight with little spray or shower effect.
Solid fire stream
On handlines should generally be operated at a maximum of _____ nozzle pressure, while master stream appliances should be operated at a maximum______.
50 psi and 80 psi
GPM = 29.7 x D2 x NP
Gpm = discharge in gallons per minute
29.7 = a constant
D = diameter of orifice in inches
NP = nozzle pressure
A _________ may be produced by deflection at the periphery, by impinging jets of water, or a combination of these methods.
Fog stream
Periphery deflected streams are produced by deflecting water around an inside circular stem in the nozzle. The water is then deflected by the exterior barrel of the nozzle. The position of the stem relative to the barrel will determine the shape of the _______
Fog stream
Is designed to flow a specific volume of water on all stream patterns at a specific nozzle discharge pressure.
A constant flow nozzle
Most _______ are designed to operate at a nozzle pressure of 100 psi. However some nozzles may operate at 50 or 75 psi.
Constant flow nozzles
These nozzles allow the firefighter operating the handline to select the flow rate to suit fire and operating conditions.
Selectable gallonage nozzles
Are a type of variable flow nozzle with the ability to change patterns while maintaining the same nozzle pressure.
Automatic fog nozzle
Operating at a pressure of up to _____ high pressure fog nozzles produce a stream with significant forward velocity but relatively low volume of water delivery.
800 psi
These nozzles are best suited for wildland fires and are not recommend for structural fire fighting due to their low water flow of only _____ to ____ gpm
8 to 15 gpm 30L/min to 60L/min
Generally, _____ is the maximum flow for a handline
350 gpm
Are capable of water flow in excess of 350 gpm and must be properly secured to a safe position. These appliances may produce solid or fog streams and generate considerable nozzle reaction due to their higher flow rate.
Master stream nozzles
Are generally operated during incidents where handlines would be ineffective, conditions require a defensive posture, or personnel are limited.
Master stream appliances
Commonly called deck guns and permanently mounted on the apparatus
Fixed monitors
Maybe used in a mount on the apparatus or removed and used remotely from the vehicle.
Combination monitors
Stored on the apparatus for deployment to the location where they will be used.
Portable monitors
Are most often lowered through holes or other openings to the cellar of an occupancy. These devices may also be deployed for attic or other void space fires.
Cellar nozzles
Also called ________ are commonly used in aircraft firefighting, car fires, or to apply water to voids, attics, or their areas inaccessible to standard fire streams.
Piercing nozzles
The piercing nozzle is generally designed as _____ to _____ hollow steel rod ______ in diameter.
3 to 6 ft 1 1/2 inches in diameter
Designed to suppress fires in chimney flues, the_______ is supplied by a booster hose. The device consists of a solid piece of brass or steel with many small impinging holes. Flowing only ____ to _____ at a nozzle pressure of______psi the impinging holes of the _______ produce a very fine mist which turns to steam in the hot interior of the chimney.
Chimney nozzles
Flowing 1.5 to 3 GPM
100 psi
This _______ illustrates Newton’s third law of motion: for every action there is an opposite equal reaction
Nozzle reaction
Nozzle reaction for solid stream nozzles
NR = 1.57 x D2 x NP
NR nozzle reaction in pounds
1.57 a constant
d nozzle diameter
NP nozzle pressure per square inch
A simple guideline for the customary system of measurement is ______ this may be used to achieve the approximate solid stream nozzle reaction on the fire ground.
NR = Q/3
Nozzle reaction for fog stream nozzles
NR = 0.0505 x Q x NP
NR nozzle reaction in pounds
0.0505 a constant
Q total flow through the nozzle in gallons per minute
NP nozzle pressure in pounds per square inch
A simple guideline for the customary system of the measurement is _______. This may be used to achieve the approximate for stream nozzle reaction on the fire ground.
NR= Q/2
Solid stream nozzles on handlines should generally be operated at a maximum of
50 psi
Although a narrow pattern is possible, impinging stream nozzles most often provide a
Wide angle fog pattern
When operating a _______, the driver operator sets its discharge gallonage with a specified range before use
Selectable gallonage nozzle
Adjust to fluctuating water flow to maintain effective pressure and a consistent fire stream in all flow ranges
Automatic nozzles
Smooth bore streams are generally operated at ____
80 psi master stream
While fog appliances are generally operated at
100 psi
As water is discharged from a nozzle at a given pressure, a counterforce pushes back against firefighters operating a hoseline. This force, called
Nozzle reaction
