CPO Pool Calculations and Formulas Questions and Answers

Question 1

An L-shaped swimming pool consists of two rectangular sections.
The first section measures 40 ft long by 20 ft wide.
The second section measures 30 ft long by 15 ft wide.
If the entire pool has an average depth of 5 ft, what is the total volume in gallons? (Use 7.48 gallons per cubic foot)

Accepted Answer

46,750 gallons

Answer

29,920 gallons

Answer

6,250 gallons

Answer

91,630 gallons

Question 2

An operator needs to calculate the filter surface area for a round high-rate sand filter that has a diameter of 36 inches. What is the correct filter surface area in square feet?

Accepted Answer

7.07 sq ft

Answer

28.26 sq ft

Answer

9.42 sq ft

Answer

1,017.36 sq ft

Question 3

A public pool with a volume of 75,000 gallons has a measured Total Alkalinity (TA) of 40 ppm. To reach the desired level of 100 ppm, how many pounds of sodium bicarbonate are required? (Dosage factor: 1.4 lbs of sodium bicarbonate raises TA by 10 ppm in 10,000 gallons)

Accepted Answer

63.0 lbs

Answer

8.4 lbs

Answer

112.5 lbs

Answer

105.0 lbs

Question 4

Using the Langelier Saturation Index (LSI) formula and the provided factors, what is the LSI for a pool with the following readings: pH = 7.2, Temp = 76°F, Calcium Hardness = 200 ppm, Total Alkalinity = 50 ppm, and TDS < 1000 ppm? (Formula: LSI = pH + TF + CF + AF - 12.1; Factors: TF=0.6, CF=1.9, AF=1.7)

Accepted Answer

-0.7

Answer

0.7

Answer

1.3

Answer

-1.5

Question 5

A 120,000-gallon public swimming pool is required by the local health code to have a turnover rate of 6 hours. What is the minimum required flow rate in gallons per minute (GPM) to meet this code?

Accepted Answer

333 GPM

Answer

20,000 GPM

Answer

1,200,000 GPM

Answer

2,000 GPM

Question 6

A 40,000-gallon pool has a Total Chlorine (TC) of 2.5 ppm and a Free Chlorine (FC) of 0.5 ppm. To achieve breakpoint chlorination, a chlorine dose of 10 times the Combined Chlorine (CC) is required. How many pounds of calcium hypochlorite (67%) are needed? (Dosage factor: 2 oz of 67% cal-hypo adds 1 ppm to 10,000 gallons)

Accepted Answer

5.0 lbs

Answer

10.0 lbs

Answer

2.5 lbs

Answer

1.25 lbs

An L-shaped swimming pool consists of two rectangular sections.The first section measures 40 ft long by 20 ft wide.The second section measures 30 ft long by 15 ft wide.If the entire pool has an average depth of 5 ft, what is the total volume in gallons? (Use 7.48 gallons per cubic foot)

An L-shaped swimming pool consists of two rectangular sections.
The first section measures 40 ft long by 20 ft wide.
The second section measures 30 ft long by 15 ft wide.
If the entire pool has an average depth of 5 ft, what is the total volume in gallons? (Use 7.48 gallons per cubic foot)