CPO Pool & Spa Maintenance & Operations 2 — Questions and Answers
Question 1: What is the recommended turnover rate for a standard commercial swimming pool?
- Every 2 hours
- Every 6 hours (Correct answer)
- Every 8 hours
- Every 12 hours
Correct answer: Every 6 hours
Most health codes require commercial pools to turn over the entire water volume every 6 hours through the filtration system.
Question 2: Which type of filter requires backwashing to clean it?
- Cartridge filter
- Diatomaceous earth filter
- Sand filter
- Both sand and DE filters (Correct answer)
Correct answer: Both sand and DE filters
Both sand filters and diatomaceous earth (DE) filters use backwashing as their primary cleaning method, reversing water flow to flush out trapped debris.
Question 3: When should a CPO operator perform a full water chemistry test?
- Once per week
- Once per month
- At least twice daily during peak season (Correct answer)
- Only when the water looks cloudy
Correct answer: At least twice daily during peak season
Commercial pool operators should test water chemistry at least twice daily, especially during periods of heavy bather load.
Question 4: What is the primary purpose of a skimmer in pool operations?
- To circulate chemicals throughout the pool
- To remove surface debris before it sinks (Correct answer)
- To monitor water temperature
- To regulate pump pressure
Correct answer: To remove surface debris before it sinks
Skimmers draw water from the pool surface to remove floating debris such as leaves, oils, and insects before they sink and decompose.
Question 5: A pool operator notices the pressure gauge on the filter is reading 10 psi above the clean starting pressure. What action is required?
- Add more water to the pool
- Increase the pump speed
- Backwash or clean the filter (Correct answer)
- Add more chlorine
Correct answer: Backwash or clean the filter
A pressure increase of 8–10 psi above the clean starting pressure indicates a dirty filter that needs backwashing or cleaning.
Question 6: What chemical is used to lower the pH in pool water?
- Sodium carbonate (soda ash)
- Sodium bicarbonate
- Muriatic acid or sodium bisulfate (Correct answer)
- Calcium hypochlorite
Correct answer: Muriatic acid or sodium bisulfate
Muriatic acid (hydrochloric acid) or dry acid (sodium bisulfate) are the most common chemicals used to lower pH in pool water.
Question 7: What is 'channeling' in the context of a sand filter?
- Water bypassing the filter media through pathways in the sand (Correct answer)
- The direction of water flow through the pump
- A method of distributing chemicals evenly
- The process of adding new sand to the filter
Correct answer: Water bypassing the filter media through pathways in the sand
Channeling occurs when water finds preferential pathways through the sand bed, bypassing the filter media and reducing filtration effectiveness.
CPO Pool & Spa Maintenance & Operations 2
What is the recommended turnover rate for a standard commercial swimming pool?