NPLQ NPLQ Water Quality and Chemical Management Questions and Answers 2

Question 1

What does 'total alkalinity' measure in pool water?

Accepted Answer

The water's ability to resist changes in pH

Answer

The amount of free chlorine present

Answer

The concentration of dissolved salts

Answer

The hardness of the water

Question 2

Which chemical is most commonly used to lower pool pH?

Accepted Answer

Muriatic acid (hydrochloric acid)

Answer

Sodium carbonate (soda ash)

Answer

Calcium hypochlorite

Answer

Sodium bicarbonate

Question 3

What is the primary health risk associated with insufficient sanitizer levels in pool water?

Accepted Answer

Spread of waterborne illnesses such as Recreational Water Illness (RWI)

Answer

Increased water temperature

Answer

Excessive foaming

Answer

Staining of pool surfaces

Question 4

At what free chlorine level should a pool typically be closed to swimmers according to CDC guidelines?

Accepted Answer

Below 1 ppm

Answer

Below 5 ppm

Answer

Below 0.01 ppm

Answer

Below 10 ppm

Question 5

What is the most common cause of cloudy or turbid pool water?

Accepted Answer

Poor filtration, high pH, or insufficient sanitizer allowing particulates to accumulate

Answer

Excess cyanuric acid levels

Answer

Too much free chlorine in the water

Answer

Water temperature below 70°F

Question 6

What does the Langelier Saturation Index (LSI) help pool operators determine?

Accepted Answer

Whether pool water is corrosive, balanced, or scale-forming

Answer

The amount of chlorine needed per gallon

Answer

The correct turnover rate for the filtration system

Answer

The ideal bather load for the pool