CPO Disinfection and Sanitizers 2

Question 1

Which chlorine product has the highest available chlorine content by percentage?

Accepted Answer

Trichlor (trichloroisocyanuric acid)

Answer

Sodium hypochlorite (liquid bleach)

Answer

Calcium hypochlorite (cal hypo)

Answer

Sodium dichlor

Question 2

What is the most effective disinfecting form of free chlorine in pool water?

Accepted Answer

Hypochlorous acid (HOCl)

Answer

Hypochlorite ion (OCl⁻)

Answer

Monochloramine (NH₂Cl)

Answer

Dichloramine (NHCl₂)

Question 3

Trichlor and dichlor are considered 'stabilized' chlorines because they contain:

Accepted Answer

Cyanuric acid (CYA)

Answer

Calcium carbonate

Answer

Sodium bicarbonate

Answer

Potassium monopersulfate

Question 4

What effect does sodium hypochlorite (liquid chlorine) have on pool pH?

Accepted Answer

Raises pH due to its highly alkaline nature

Answer

Lowers pH significantly

Answer

Has no effect on pH

Answer

Lowers total alkalinity only

Question 5

Which calcium-based chlorine product will gradually increase total calcium hardness in pool water?

Accepted Answer

Calcium hypochlorite (cal hypo)

Answer

Trichlor tablets

Answer

Sodium hypochlorite

Answer

Sodium dichlor

Question 6

Why must calcium hypochlorite (cal hypo) and trichlor NEVER be mixed or stored together?

Accepted Answer

The combination can cause a violent fire or explosion

Answer

They cancel each other's disinfection effect

Answer

They produce excess cyanuric acid

Answer

They lower pH to dangerous levels

Question 7

What is the recommended free chlorine range for a commercial swimming pool under the Model Aquatic Health Code?

Accepted Answer

1.0–5.0 ppm

Answer

0.1–0.5 ppm

Answer

5.0–10.0 ppm

Answer

10.0–20.0 ppm