Assessment 2 Flashcards
The concept of pumping operations is based on what?
Creating pressure differentials
What is the definition of pressure?
The amount of energy in water
When using the hard suction, how can you tell you are receiving the maximum amount of water from the hydrant outlet?
Increase in pump speed without an increase in pressure
Does pressure have an effect on friction loss?
No
What is the characteristic of water that is important for firefighting?
Density
What is water differential a difference in?
Quantity
What is the type of pressure remaining when a valve is open and the water is flowing?
Residual pressure
What is the maximum efficient water capacity of 2.5” hose without excessive friction loss?
250 gpm
What is the net pump pressure when drafting?
Discharge pressure + FL in hose + lift psi
What is the definition of gear split?
When engine speed reaches the point that the transmission should be shifted
In a water relay, where are shutdowns initiated?
At the source of supply
Water particles creating friction accounts for what percent of friction loss in the hose?
90 percent
What might an air leak cause in a centrifugal pump?
Failure to prime
How is net pump pressure calculated?
Intake pressure - discharge pressure
Where does cavitation in a centrifugal pump usually occur?
Impeller eye in back of the blade
What is the highest pressure the pump panel discharge gauges show?
600 psi
In a syphon ejector, where is the velocity of the water converted to pressure greater than the suction pressure?
In the diffuser
When using the syphon ejector, feet of head is determined by measuring from the water source to what?
The center of the pump
When using the Gleason valve, how do you know you have sufficient pressure on the supply side?
Water will flow from the overflow
How far should the radio antenna be held from the eye?
6”
Best results during the initial priming operation are achieved with the impeller…
Stationary
When shut down for an extended period of time during a drafting operation, what can be done to prevent the water from heating up?
Open a discharge gate bleeder valve
In a relay operation, the second pump on scene shall charge his line to what pressure?
Idle
What kind of pump packing seals are used by the LAFD?
Mechanical
What is the hand signal to shut down the water source?
Hold both hands overhead with finger tips touching
When should pressure control devices be set on the pump?
As soon as desired engine pressure is obtained
What does the height to which a pump can draft rely on?
Atmospheric pressure
When drafting, the rated capacity of the pump will not be obtained when lift exceeds how many feet?
10’
What type of threads are on hydrants?
National Standard
The F-367 hydrant report, shall be completed and sent to the hydrant access unit within how many days?
14
How often is the earthquake packet checked?
Every 4 months
