Chapter 6

Question 1

What factors effect the condition of the stream as it exists the nozzle?

Answer 1

Operating pressure, nozzle design and adjustment, condition of the nozzle orifice

Question 2

What factors influence the fire stream from when it leaves the nozzle and when it reaches its destination?

Answer 2

Velocity, gravity, wind, friction with the air

Question 3

What 3 types are of nozzles operated by the fire service?

Answer 3

Solid, fog, and broken stream

Question 4

solid fire stream

Answer 4

Is produced with a fixed orifice and a smooth bore nozzle and stays together as a light stream with little spray or shower effect

Question 5

What type of hose lines smooth bore nozzles?

Answer 5

Handling and master streams

Question 6

How are solid stream nozzles designed?

Answer 6

Sothat water flowing through the nozzle is reduced gradually so that the water has a smooth shape at discharge. The smooth waterway helps maximize the reach of the stream.

Question 7

What determines the flow and reach of as solid stream?

Answer 7

The size of the discharge and the nozzle pressure.

Question 8

What psi should hand lines with a solid stream nozzle be operated at?

Answer 8

50psi

Question 9

What psi should master streams with a smooth bore nozzle be operated at?

Answer 9

80psi

Question 10

How do fog nozzles break streams of water in to finely divided particles?

Answer 10

That stream is driven up against an obstruction with sufficient force to diffuse the water and shatter the mass.

Question 11

In a fog nozzle what does the pattern of deflection determine?

Answer 11

The forward velocity of the stream of water, the pattern of the final stream and the shape.

Question 12

In what ways does fog nozzles produce fog streams?

Answer 12

Deflection at the periphery, impinging streams of water, or both.

Question 13

What are periphery-deflected fog streams?

Answer 13

Are produced by deflecting the water around a circular stream inside the nozzle. Then the water is deflected by the outside barrel of the nozzle. The position of the stem relative to the barrel will determine the shape of the stream.

Question 14

How do impinging stream nozzles break streams of water into five evenly divided particles?

Answer 14

By driving several sets of water together at an angle.

Question 15

What angle of fog pattern do impinging stream nozzles most often provide?

Answer 15

Wide angle (but narrow is possible)

Question 16

Besides impinging stream nozzles, what other kinds of nozzle can impinging jets be used?

Answer 16

Periphery deflected stream nozzles

Question 17

What 4 things directly affect the reach of a fog stream?

Answer 17

The stream width, the size of the water droplets, the wind and the volume of water flowing.

Question 18

What is a constant flow nozzle?

Answer 18

Is designed to flow a specific volume of water on all stream patterns at a specific discharge pressure.

Question 19

How do continuous flow nozzles operate?

Answer 19

The exterior of the barrel rotates in order to adjust the flow pattern. However, the space between the deflecting stem and the interior throat of the nozzle remains the same, allowing for the same gallonage of water to be discharged on every pattern settings.

Question 20

What are selectable gallonage nozzles?

Answer 20

Allow firefighters in the nozzle to select the flow rate at the nozzle based on the conditions encountered.

Question 21

What is a disadvantage of the selectable gallonage nozzle when operating on the fire line?

Answer 21

The driver/operator must know what gallonage has been selected in order to calculate the correct discharge pressure.

Question 22

What are adjustable fog nozzles?

Answer 22

A type of variable flow nozzle with the ability to change patterns while maintaining a constant flow. If the gallonage supplied to the nozzle changes the nozzle automatically changes to maintain the same pressure and pattern

Question 23

What are most for nozzles designed to operate at?

Answer 23

100 psi

Question 24

What are high pressure fog nozzles?

Answer 24

Nozzles that produce a stream with significant forward velocity but low volume.

Question 25

What pressures do high pressure fog nozzles operate at?

Answer 25

Greater than 100 psi but not greater than 800 psi

Question 26

Why are high pressure fog nozzles not recommended for structural firefighting?

Answer 26

Because of their low water flow 8-15gpm. They are often used asan impinging stream in wildland fire.

Question 27

What is usually considered the maximum flow of a handline nozzle?

Answer 27

350 gpm

Question 28

Why are nozzles that flow greater than 350 gpm not usually used as handlines?

Answer 28

The nozzle reaction produced by the greater Flows will be difficult/ dangerous for a fire fighter on a handline to handle

Question 29

What nozzles flow greater than 350 gpm?

Answer 29

Master stream nozzles

Question 30

What kinds of streams can be produced by master stream nozzles?

Answer 30

Fog and solid stream

Question 31

What situations would require a master stream over a hand line?

Answer 31

Fires with heavy fire volume, when conditions require a defensive technique, limited number of personnel, when a farther reach is required for the water stream.

Question 32

What are smooth bore master streams usually operated at?

Answer 32

80 psi

Question 33

What pressure are fog master stream appliances usually operated at?

Answer 33

100 psi

Question 34

What are the three types of master steam appliances?