CPO CPO Filtration & Circulation Systems

Question 1

What is the standard turnover rate required for most public swimming pools?

Accepted Answer

6 hours

Answer

Most public pools require a 6-hour turnover rate, meaning the entire pool volume must pass through the filtration system at least once every 6 hours.

Question 2

When should a sand filter be backwashed?

Accepted Answer

When pressure rises 8–10 psi above the clean operating pressure

Answer

A sand filter should be backwashed when the pressure gauge reads 8–10 psi above the initial clean/starting pressure, indicating accumulated debris.

Question 3

What is the primary purpose of a hair and lint strainer (pump strainer basket)?

Accepted Answer

To protect the pump impeller from debris damage

Answer

The hair and lint strainer captures large debris before it reaches and damages the pump impeller, protecting the pump from wear and clogging.

Question 4

What filtering medium is used in a diatomaceous earth (DE) filter?

Accepted Answer

Fossilized algae powder coated onto filter grids

Answer

DE filters use diatomaceous earth — a powder made from fossilized microscopic algae — coated on filter grids to achieve very fine particle filtration.

Question 5

What causes 'channeling' in a sand filter?

Accepted Answer

Water finding preferential paths through worn sand instead of flowing evenly

Answer

Channeling occurs when water bypasses proper filtration by carving paths through degraded or compacted sand, significantly reducing filter effectiveness.

(CPO) Certified Pool and Spa Operator Practice Test

(CPO) Certified Pool and Spa Operator Practice Test

CPO CPO Filtration & Circulation Systems