CSLB C-53 Swimming Pool (Trade Exam) — All Questions

A pool drops 1-1/2 inches per day. A bucket on a step drops 1 inch in the same time. What is the likely conclusion?

• a.A sound pool, since both levels dropped
• b.A chemistry problem in the water
• c.A leak of about 1/2 inch a day✓
• d.A large leak of 2-1/2 inches per day

The excess drop beyond evaporation is 1.5 − 1.0 = 0.5 inch per day, so a small leak is likely. Both dropping does not mean no leak, 2.5 inches adds the numbers, and level loss does not diagnose chemistry.CSLB C-53 outline (Water loss and discoloration)

A 20 by 30 foot pool loses 1/2 inch more than the bucket per day. At 7.5 gallons per cubic foot, how many gallons are lost to the leak per day?

• a.About 25 gallons
• b.About 1,500 gallons
• c.About 188 gallons✓
• d.About 4,500 gallons

Volume is 600 square feet × (0.5 ÷ 12) = 25 cubic feet, and × 7.5 = 187.5 gallons. The 25 figure is cubic feet, 1,500 treats the drop as 4 inches, and 4,500 is the surface area times 7.5.CSLB C-53 study guide 13E-53 (computation questions)

What does automatic makeup water do to a leak's visibility?

• a.It stops the leak as the level rises
• b.It makes the leak larger over time
• c.It can hide a leak by refilling✓
• d.It changes the pH of the water

Automatic makeup water keeps the level up, so the leak shows up as higher water usage. It does not enlarge or stop the leak or change chemistry.2025 CBC §3127B.3

Brown water appears after the fill source is switched to a well. What comes first?

• a.Test the water for metals and balance✓
• b.Drain the pool to refill with city water
• c.Add heavy chlorine to clear it up
• d.Replace the sand in the filter

Brown discoloration often indicates dissolved iron or other metals, which a test confirms before any treatment. Draining without checking groundwater, heavy chlorine and new sand do not address the source.CSLB C-53 outline (Water loss and discoloration)

Why check groundwater before draining a pool?

• a.The tile will change color in the sun
• b.The plaster finish will melt on drying
• c.The pump will run dry and burn up
• d.An empty shell can lift✓

A high water table can push on an empty shell, and public pools in such areas require a hydrostatic relief device. Sun does not change tile color this way, plaster does not melt on drying, and draining the pool does not make the pump burn up.2025 CBC §3137B.1

What crack width does the shotcrete association's statement describe as reasonable for watertightness in water-retaining structures?

• a.Up to about 0.004 inch✓
• b.Up to about 1 inch
• c.Up to about 1/2 inch
• d.Up to about 0.5 inch

The position statement says crack widths of up to 0.004 inch are reasonable for watertightness. Half an inch and an inch are far wider.American Shotcrete Association Position Statement #8

Which condition increases shrinkage cracking in a new shell?

• a.Seven days of continuous wet curing
• b.Cleaning the joints before the next lift
• c.Skipped curing in hot, dry or windy weather✓
• d.Placing at the right slump for the job

The FAQ says lack of curing and exposure to windy, hot or dry conditions increase shrinkage and cracking. Seven days of wet curing, cleaning joints before the next lift and placing at the right slump are all good practice.American Shotcrete Association Pool FAQ

A permit is issued to remodel an existing private-home pool. What must it require about the safety features?

• a.A single listed safety feature
• b.The seven listed safety features
• c.Waived features, since the pool already exists
• d.At least two of the seven safety features✓

The Act applies when a permit is issued for remodeling an existing pool or spa at a private single-family home, requiring at least two of seven. A single feature falls short, all seven is more than the Act requires, and the features are not waived for an existing pool.Health and Safety Code §115922

What must a permit for remodeling an existing pool require for its suction outlets?

• a.Upgrade to entrapment grates✓
• b.Capping of the existing outlets
• c.Painting of the existing outlets
• d.Removal of the existing outlets

The permit requires existing suction outlets to be upgraded to anti-entrapment grates meeting the ANSI/APSP-16 standard or successor. Capping, painting or removing the outlets does not provide the required grate.Health and Safety Code §115928.5

What surface preparation does the association recommend for new shotcrete on old concrete?

• a.A smooth dry surface with bonding agent
• b.A painted surface left to dry first
• c.A polished wet surface under standing water
• d.A rough SSD surface, no bonding agent✓

The FAQ recommends roughening about 1/16 inch, cleaning, SSD and no bonding agent. A smooth dry surface with a bonding agent, a painted surface and a polished surface under standing water all interfere with bond.American Shotcrete Association Pool FAQ

A homeowner wants to thicken a 3-inch wall by 6 inches. What should the contractor do?

• a.Use a bonding agent in place of steel
• b.Skip the curing to save time
• c.Pour without changing the steel
• d.Have the designer check the steel✓

Added thickness would require more reinforcing steel, so the designer verifies. Pouring without steel changes or skipping curing is unsafe, and a bonding agent is not a substitute.American Shotcrete Association Pool FAQ

What triggers a public wading pool alteration under the code?

• a.Replacing a burned-out light bulb
• b.Repairs costing $50 or more✓
• c.Cleaning the filter cartridges
• d.Painting the deck around the pool

Alteration includes changing the structure, enlarging, moving, installing a new circulation system, and making repairs costing $50 or more to the circulation system. Painting, cleaning and a bulb are not alterations.2025 CBC §3161B

Who must get a plan approved before renovating a public pool?

• a.Plans go to the equipment supplier
• b.Plans go to the neighbors for a vote
• c.Enforcing agent approval first✓
• d.Plans go to the tile contractor

The code requires plans for construction, renovation or alteration of a public pool to be approved in writing by the enforcing agent before work begins. The equipment supplier, the neighbors and the tile contractor have no approval authority.2025 CBC §3103B.1

Which new metal item in the bonding zone must be bonded after a remodel?

• a.A plastic skimmer lid in the deck
• b.A wooden bench free of fittings
• c.A rubber mat beside the steps
• d.A metal ladder or handrail nearby✓

Metal items and fittings for handrails, ladders, drains and diving boards within the zone are bonded. Plastic, wood and rubber are nonconductive.City bonding handout (Menifee), 2022 CEC §680.26

Which statement describes the sequence for removing a pool?

• a.Bury the shell without notice given
• b.Fill the pool with water and leave it
• c.Permit, disconnect, drain, fill, inspect✓
• d.Cover the pool with a tarp and wait

Removal needs a permit, utility disconnection, controlled drainage, shell treatment, engineered fill and inspection. Filling with water, tarping and burying skip the required steps.CSLB C-53 outline (Pool/Spa Repair, Renovation, Removal, and Maintenance)

What must be done before servicing a pump?

• a.Lock out, tag out and relieve pressure✓
• b.Spray the pump with water to cool it
• c.Remove the GFCI to stop nuisance trips
• d.Open the lid while the pump runs

Control of hazardous energy requires locking out, tagging out, verifying and relieving stored energy. Spraying water, removing the GFCI and opening the lid while the pump runs each create a hazard.Title 8 §3314

A replacement gas pool heater must have which features?

• a.A pilot light without an on-off switch
• b.A thermostat dial in place of a switch
• c.A standing pilot for easier starts
• d.A switch and no standing pilot✓

Heaters require an externally mounted, readily accessible switch and gas heaters may not have a continuously burning pilot. A pilot without a switch, a thermostat dial in place of a switch and a standing pilot each violate one or both rules.2025 Energy Code §110.4(a), §110.5

What must replacement pump circuits have?

• a.An unbonded casing and a plain breaker
• b.A standing pilot light on the motor
• c.Skipped grounding on the pump
• d.GFCI and a bonded motor casing✓

Pool pump motor circuits need GFCI protection, and motor casings are bonded. An unbonded casing, a pilot light on a motor and skipped grounding are unsafe or unrelated.City electrical and bonding handouts (Menifee)

A public rapid sand filter must contain what depth of media?

• a.Not less than 20 inches✓
• b.Not less than 10 feet
• c.A depth that fits the tank
• d.Not less than 2 inches

The filter contains not less than 20 inches of media and not less than 10 inches of gravel above the underdrain. A depth of 2 inches is too shallow, 10 feet is far too deep, and a depth that fits the tank is no stated minimum.2025 CBC §3129B.2

A public cartridge filter vessel must be capable of what?

• a.Draining through an indirect drain✓
• b.Being buried below the equipment pad
• c.Being painted to match the equipment
• d.Being left dry between cleanings

The filter vessel must be capable of being drained and equipped with an indirect drain. Burying the vessel, painting it and leaving it dry between cleanings have nothing to do with draining.2025 CBC §3132B.2

A replaced suction outlet cover must meet which condition?

• a.It is optional on small pumps
• b.Needs tools to remove✓
• c.It has wide slots for easy flow
• d.It snaps off by hand for cleaning

Anti-entrapment grates cannot be removed except with tools and have openings shaped to prevent entrapment. A cover that is optional, has wide slots or snaps off by hand creates an entrapment or removal hazard.Health and Safety Code §115928

What does the pump pressure gauge reading above clean baseline with low flow indicate?

• a.An empty basket in the strainer
• b.A low water level in the pool
• c.A dirty filter or clogged return✓
• d.A closed skimmer line to the pump

High pressure with low flow means resistance after the pump, such as a dirty filter. A low level, empty basket or closed skimmer would raise vacuum or starve the pump.CSLB C-53 outline (Equipment and systems)