P&A Ch. 8 - Fireground Hydraulic Calculations

In what mode does the electronic pressure governor need to be so that it will compensate for hoseline shutdown during operations?

Psi

What is a mechanical device that is installed in a discharge line that senses the amount of water flowing?

Flowmeter

Which type of flowmeter is mounted on the top of a straight section of the discharge pipe and reduces the impediment to water flow?

Paddlewheel

What must be subtracted from the first two numbers of the gpm flow when factoring the flow in gallons per minute from the nozzle at a given pressure?

10

What are charts that are carried on a fire apparatus to aid in determining the proper pump discharge pressure when supplying hoselines?

Pump charts

What should be added together when operating an apparatus with flowmeters to determine the rate that should be pumped?

Flow rate for each nozzle

Which size hoseline can the Condensed Q formula not be used on to determine friction loss?

2-inch

What percent greater will the friction loss result be than the traditional formula when using the Condensed Q formula?

20 percent

How many times more water would a 2 1/2 inch hoseline need to be flowing to equal the same friction loss in a 1 1/2 inch hose line?

Four times

What happens to the spring in the spring probe as more water flows?

It is bent

What should the margin of error be when proper calibration of a flowmeter?

Plus or minus 3 percent

Below what flow rate is the gpm flowing method NOT applicable to 2 1/2 inch hoselines?

160 gpm

What can be done to determine the correct discharge pressure when performing relay pumping?

Increase the engine speed until the flowmeter reading no longer increases

Where should the pump discharge pressure provide for residual pressure when performing relay pumping calculations?

Intake of the pumper being supplied

Within what distance from the control valve for the discharge must the digital readout be located when it is equipped with a flowmeter?

6 inches

Under NFPA 1901, what increments must the flowmeter display flow as a maximum?

10 gpm

How much does the friction loss increase for every 10 gpm increase in flow in 2 1/2 inch hoseline?

1 psi