Chapter 7 Fire Hose Nozzles and Flow rates


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What are the three basic types of fire streams? Solid, Fog, and Broken.
What other type of stream can a fog stream nozzle create? Psuedosolid (Straight stream).
What is the length of a solid stream nozzle usually and why? One to one and one-half times its diameter. And its purpose is to give the water its round shape before discharge.
What is the formula for determining the flow from a solid stream? GPM=29.7(d)^2 (square root of the nozzle pressure)
What are Constant Flow Nozzles? Designed to flow a specific amount of water at a specific nozzle discharge pressure on all stream patterns.
Most constant flow nozzles are intended to be operated at a nozzle pressure of? 100 psi, although there are some lower pressure nozzles that operate at 50 to 75 psi.
What is a Manually Adjustable Nozzle (Adjustable Gallonage Nozzle)? Has a number of constant flow settings, enabling the firefighter to select a flow rate that best suits the existing conditions.
What is the minimum flow setting for interior structural fire fighting? 95-100 gpm.
What are Automatic Nozzles? Also referred to as constant pressure nozzles or multipurpose nozzles. Are basically variable fow nozzles with pattern change capabilities with the ability to maintain the same nozzle pressure.
What is the most common variable flow nozzles in use today? Automatic Nozzles.
What psi does High-Presssure fog nozzles operate at? pressures up to 800 psi.
What type of nozzles are best for wildland fires? High-Pressure Nozzles and lines (only flow 8-15 gpm).
What is a Master Stream? Any stream that is too large to be controlled w/out mechanical aid.
What are the four basic categories of master stream devices? Monitor, Turret, Deluge and Elevated Master Stream
What is unique about the Monitor? The stream direction and angle can be changed while water is being discharged.
Which master stream is mounted on a fire app deck and is connected directly to the pump by permanent piping? Turret Pipe.
What is unquie about the Deluge Set? has a short length of LD hose, siamese connection at the supply end, and the direction/angle of the stream cannot be changed while discharging water
What is an Elevated Master Stream? Ladder pipe/aerial device
What is the difference between Broken Nozzles and Fog Nozzles? Fog uses deflection or impinging streams. Broken Streams are created when water is forced through a series of small holes on the discharge end.
What type of stream produces larger droplets of water, and what is the advantage? Broken stream and this tends to give the stream better reach and penetrating power.
What are Water Curtain nozzles and what are they most effective in? Produce a fan shaped stream intended to protect combustible materials from the heat of an adjacent fire. Only effective in absorbing convected heat from fires.
Explain a Piercing Nozzle (Penetrating Nozzle). Commonly used in aircraft fires, or voids or attics below lightweight roof systems and AFFF in a confined area. Driven into concrete with a sledgehammer.
What is Nozzle Reaction? The force pushing back on the fire fighters handling the hose.( Newton's Third Law of Motion) Greater discharge pressure the greater the reaction
Is the driver/operator usually responsible for selecting an appropriate nozzle to perform an evolution? No. But they must undrstand the capabilities of each nozzle in order to support it.
What is a fire stream influenced by? Velocity, gravity, wind, and friction with the air
What is a Periphery fog stream? The line bounding a rounded surface; the outward boundary of an object distinguished from its internal regions.
What is a Deflection Fog stream? A turning or state of being turned; a turning from a straight line or given course; a bending; a deviation
What is a fire stream? Stream of water or other extinguishing agent after it leaves a nozzle until it reaches the desired point.
What is a Impinge fog stream? To strike or dash about or against; clashing with a sharp collision; to come together with force
What is the reach of a fog stream directly dependent on? The width of the stream, the size of the water droplets, wind and the amount of water flowing.
Most Manually adjusted nozzles are designed to supply how much gallonage? 100 psi NP
What is the minimum flow for interior structure FF? 95-100 gpm
High pressure fog nozzles operate up to? 800 psi
What are the three basic types of monitors? fixed, portable and combination
A fog stream that drives several jets of water together @ a set angle to break the water up into finely divided particles is? Impinging stream
What are the 4 types of fog stream nozzles? Constant flow, Manually adjustable, Automatic(Constant pressure), and High Pressure Nozzles
What master stream is also called a deck gun? Turret
According to IFSTA, tests have revealed that the practical working limits for velocity of fire streams are w/in how many feet? 60-120 feet
Most constant flow nozzles use what type of mechanical principle? Periphery-Deflected stream
A Periphery-Deflected stream is usually used on what type of nozzle? Constant Flow nozzle
What type of stream is High Pressure Fog? Impinging stream
What is a Turret sometimes called? Deck Gun
What pressure can solid hand lines be raised if greater reach and volume is needed? 65 psi
What is the practical working limits for velocity of fire streams? 60-120 feet per second (25-100 psi)
How may a fog stream be produced? By deflection at the periphery or by impinging jets at the periphery or by combination
What type of fog pattern does impinging stream nozzles usually produce? wide-angle fog pattern