LEARN HOW TO OPERATE YOUR PUBLIC POOL SPA FACILITY
Area of a square or rectangle:
Area (A) = Length (L) x Width (W)
The x is a way to indicate the word(s) multiply or times.
The formula is simplified as A = L x W
Area of a Circle:
Area (A) = πxr2
The π is a constant number 3.14.
The r stands for radius, which is the distance from the center of the circle to the outer
edge of the circle. The radius is 1/2 of the diameter.
r2 means radius squared, or simply r times r.
The formula is better understood if written as: A = 3.14 x r x r
Examples:
(1) You have a pool with a length of 60 feet and a width of 35 feet.
What is the area?
The formula is A = L x W
L (Length = 60 ft, W (Width) = 35 ft
A = L x W
A = 60 ft x 35 ft
A = 2,100 ft2
(1) You have a circle with a diameter of 8 feet.
What is the area?
The formula is A = 3.14 x r x t
But what is r? Well the radis is 1/2 the diameter.
Therefore r = 1/2 of 8, or 4 feet
A = 3.14 x r x r
A = 3.14 x 4 ft x 4 ft
A = 3.14 x 16 ft2
A = 50.24 sq. ft.
How about a sample problem similar to a class problem?
What is the surface area of a rectangular pool with a length of 20 meters and a width of
20 yards?
We will use a series of "plug-and play" boxes in the CPO® class. Just plug
the correct number as given by the problem to perform the math (play) as indicated. Let's try it out.
The formula for a rectangle is: A = L x W
A = x
Just Plug the numbers in and Play the formula
Remember the meters and yards conversions.
Number of meters x 3.24 = number of feet (from the Main page)
Length = 20 meters (from the problem) x 3.28 Length = 65.6 ft
Number of yards x 3 = number of feet (form the Main page)
Width = 20 yards (from the problem) x 3 Width = 60 ft
A = x=
Just as a reminder, knowing how to calculate area is important for determining
heat loss, sizing pool covers, bather loads in spas, and in some states, bather loads in pools.