Pump Manual - Definitions

Question 1

Atmospheric pressure

Answer 1

14.7

Affects amount of vacuum that can be generated inside a pump and how high water can be drafted

Question 2

Back flushing

Answer 2

Flowing water through a discharge and out of an intake to remove debris

Question 3

British Thermal Unit (BTU)

Answer 3

energy needed to cool or heat one point of water by one degree Fahrenheit

Question 4

Critical application rate (CAR)

Answer 4

GPM per sqft of foam needed to extinguish flammable liquid fires

0. 1 GPM/sqft for hydrocarbons
1. 2 GPM/sqft for polar solvents

Question 5

Critical velocity

Answer 5

Point at which sped of water from a centrifugal pump creates so much turbulence that it makes it impossible to move any more water

Question 6

Dependable lift

Answer 6

height that a column of water can be lifted to provide a reliable fire flow

14.7 ft at sea level

Question 7

Freeman’s formula

Answer 7

Calculates GPM flow from solid bore/hydrant

GPM = 29.7 x D^2 x sqrt(NP)

Question 8

Dual pumping

Answer 8

Using a strong hydrant to supply two pumpers by connecting intake to intake

Question 9

Eductor rate (ED)

Answer 9

Application % for eductors:

3% for hydrocarbons
6% for polar solvents
Class A: 0.1 - 1.0%

Question 10

Expansion rating ratio

Answer 10

Expansion ratio assigned to aeration nozzles and foam expanding attachments used as part of a formula to calculate the amount of area that aerated foam will cover

Question 11

FDC standard pressure for spinklers

Answer 11

150 PSI

Question 12

Fire Load

Answer 12

Avg weight lbs/sqft of contents of a room

Avg begroom has 4.3 lbs/sft

Question 13

Fuel load

Answer 13

Total quantity of combustible contents of a building, space or fire area including interior finish and trim.

Expressed in heat units of equivalent weight in wood

Question 14

Head pressure

Answer 14

For every 1’ increase in elevation .434 PSI increase

e.g. 5 lbs per floor

Question 15

Master stream

Answer 15

large caliber hose that flows 350 GPM or more

Question 16

Maximum lift

Answer 16

Height a pumper in good condition can be expected to life water at draft.

Generally considered 2/3 of the theoretical life, or between 22-25 feet

Question 17

Max dependable flow

Answer 17

75% of the total capacity of an engine

this is the max flow for an engine during a relay operation

Question 18

Needed Fire Flow (NFF)

Answer 18

The amount of water (in GPM) needed to control the fire within 1 min

Question 19

Normal operating pressure

Answer 19

Pressure in a water system during regular domestic consumption

Question 20

Parallel (Volume) mode

Answer 20

In a two-stage pump, source water flows from intake into the eye of both impellers simultaneously

Each impeller pumps 50% of that rated GPM capacity of the pump

Question 21

Priming Pump

Answer 21

Positive displacement pump that pumps air out of centrifugal pumps…when activated, reduces pressure inside pump below 14.7 (atmospheric pressure)

Question 22

Pump Discharge Pressure Formula

Answer 22

PDP = NP + FL +- EP + AFL

Question 23

Reasonable Efficiency

Answer 23

% of water that is actually converted into steam in a fire = 80%

Question 24

Series (Pressure) mode

Answer 24

First stage impeller increases pressure and dishcarges 50-70% of the volume capacity through the transfer valve and into the eye of the 2nd impeller

Question 25

Specific heat

Answer 25

amount of heat needed to raise the temp of a specific quantity of material, and the amount of heat needed to raise the temp of a identical weight of water by the same # of degrees (measured in BTUs)

Question 26

Static pressure

Answer 26

Stored potential energy available to force water through pipes, fittings, fire hose, and adapters while water is at rest

Question 27

Tandem pumping

Answer 27

Short relay. Pumper at water source pumps to the intake of second pumper.

Used when pressures higher than the capabilities of a single pump are required.

Question 28

Theoretical lift

Answer 28

Theoretic height that a column of water can be lifted by atmospheric pressure in true vacuum

33.9 ft at sea level (14.7 x 2.304 psi = 33.9)

Question 29

Total pressure

Answer 29

PSI X number of square inches in a cross-section of an area upon which force is exerted

Question 30

Type 1 Pumper

Answer 30

100% of its rated capacity at 150 psi
70 % of its rated capacity at 200 psi
50% of its rated capacity at 250 psi

Measured from draft lifting water at least 10 ft