Formulas

Question 1

What is the formula for determining volume for a rectangular or square shaped container?

Answer 1

Capacity in gallons=L’xW’xD’x7.5(number of gallons in a cubic foot of water)

Question 2

What is the formula to determine the volume of a cylinder, pipe, or hose in gallons?

Answer 2

Capacity in gallons=(Pi)x r² x H’ (or L’) x 7.5 gallons

Where
Pi=3.14
r= radius or 1/2 of the diameter in feet
H= average height/depth in feet

Question 3

What is the formula for determining the flow from a smooth bore nozzle when nozzle pressure is known?

Answer 3

GPM= 29.7 x d² x √NP

Question 4

What is the formula to determine percentage of loss from static and residual pressures?

Answer 4

(SP-RP)100/SP

Question 5

What are the percent drop categories and their corresponding like volumes amounts?

Answer 5

0-10% = 3 times
11-15% = 2 times
16-25% = 1 times
>25% = Less than 1 times

Question 6

What is the formula to determine nozzle reaction for a smooth bore nozzle?

Answer 6

NR = 1.57 x d² x NP

Question 7

What is the formula to determine nozzle reaction for a fog nozzle?

Answer 7

NR = .0505 x Q x √NP

Question 8

Formula for calculating friction loss.

Answer 8

FL=CQ²L

Q=flow rate in hundreds of gpm (flow/100)
L=length in hundreds of feet (length/100)