CPO Advanced Professional Practice 3

Question 1

A pool operator wants to calculate the Langelier Saturation Index (LSI). Which set of factors is required?

Accepted Answer

pH, temperature, calcium hardness, total alkalinity, TDS

Answer

The LSI is calculated using pH, water temperature, calcium hardness, total alkalinity, and TDS to assess water balance and corrosion/scale potential.

Question 2

A pool using a saltwater chlorine generator (SWG) shows consistently low free chlorine despite the generator running at 100%. The MOST likely cause is:

Accepted Answer

Low salt concentration in the water

Answer

If CYA is very high, chlorine activity is suppressed, but low salt concentration directly reduces the amount of chlorine the electrolytic cell can generate.

Question 3

Under OSHA standards, which personal protective equipment (PPE) is required when handling concentrated (35%) sodium hypochlorite?

Accepted Answer

Chemical-resistant gloves, goggles, and apron

Answer

Concentrated hypochlorite is a strong oxidizer and corrosive; OSHA requires chemical-resistant gloves, splash goggles, and a protective apron to prevent skin and eye injury.

Question 4

A public pool must post maximum bather load (MBL) calculations. Using the standing room formula, a pool with 1,200 sq ft of surface area yields an MBL of:

Accepted Answer

200 bathers

Answer

The standing room formula uses 6 sq ft per bather: 1,200 ÷ 6 = 200 bathers maximum.

Question 5

A pool operator discovers that the ORP (oxidation-reduction potential) reading is 650 mV but free chlorine measures 1.5 ppm. The BEST explanation is:

Accepted Answer

High CYA is reducing chlorine's oxidizing power despite adequate free chlorine

Answer

CYA binds free chlorine and lowers ORP; even with measurable free chlorine, high CYA reduces the electrochemical activity that ORP sensors detect.

(CPO) Certified Pool and Spa Operator Practice Test

(CPO) Certified Pool and Spa Operator Practice Test

CPO Advanced Professional Practice 3