CPO Disinfection and Sanitizers Questions and Answers 2

Question 1

What is the minimum free chlorine residual required for a public swimming pool according to most state health codes?

Accepted Answer

1.0 ppm

Answer

0.5 ppm

Answer

2.0 ppm

Answer

3.0 ppm

Question 2

What is the difference between free chlorine and combined chlorine in pool water?

Accepted Answer

Free chlorine is available to sanitize while combined chlorine has reacted with nitrogen compounds

Answer

Free chlorine is less effective than combined chlorine

Answer

Combined chlorine is the total of all chlorine in the pool

Answer

There is no practical difference between the two

Question 3

What process is used to eliminate chloramines from pool water?

Accepted Answer

Superchlorination or breakpoint chlorination

Answer

Adding muriatic acid

Answer

Lowering the water temperature

Answer

Adding a clarifier

Question 4

Which form of chlorine has the lowest pH and tends to lower pool water pH when added?

Accepted Answer

Trichlor (trichloroisocyanuric acid)

Answer

Calcium hypochlorite

Answer

Sodium hypochlorite

Answer

Lithium hypochlorite

Question 5

What is the recommended maximum cyanuric acid level for outdoor public pools?

Accepted Answer

100 ppm

Answer

30 ppm

Answer

50 ppm

Answer

There is no recommended maximum

Question 6

What alternative sanitizer is approved by the EPA for primary pool disinfection alongside chlorine and bromine?

Accepted Answer

None of the above, only chlorine and bromine are EPA-approved primary sanitizers

Answer

Hydrogen peroxide

Answer

Ozone alone

Answer

UV light alone