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