CSLB C-53 Swimming Pool (Trade Exam) — All Questions
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40 questions
A filter backwash line ends a few inches above a floor drain with a visible gap. What does this arrangement represent?
- a.A pressure relief arrangement on the filter
- b.A direct connection to the sewer line
- c.A cross-connection to the potable supply
- d.An indirect waste with an air gap✓
A visible air gap between the waste pipe and the receiving fixture is an indirect waste, so sewage cannot siphon back into the equipment. A direct connection has no gap, a cross-connection links potable water to the pool, and a relief arrangement is a different device.2025 CBC §3141B.1, §3141B.5
Which order follows the water path through a pool's equipment pad?
- a.Sanitizer, heater, pump and strainer, filter, returns
- b.Pump and strainer, filter, heater, sanitizer, returns✓
- c.Filter, pump and strainer, sanitizer, heater, returns
- d.Heater, filter, pump and strainer, returns
Water leaves through skimmers and drains, passes the pump and its strainer, goes through the filter, then the heater and sanitizer, and returns to the pool. Starting at the sanitizer or heater puts equipment ahead of the pump, the filter-first order puts the filter ahead of the pump, and the heater-first order sends unfiltered water to the heater and leaves out the sanitizer.CSLB C-53 outline (Plumbing)
What protects the potable supply at a public pool deck hose bibb?
- a.A decorative cap chained to the bibb
- b.A removable screen over the outlet
- c.A rubber washer in the handle
- d.A nonremovable backflow device✓
Potable outlets with hose attachments need a nonremovable hose bibb backflow preventer, a nonremovable vacuum breaker or an atmospheric vacuum breaker. A screen, cap or washer does not stop backflow.2025 CBC §3118B
What does the Energy Code require between a filter and a heater?
- a.A direct flanged joint between the two units
- b.A shutoff valve at each end of the heater
- c.18 inches of pipe, or dedicated lines✓
- d.A pressure gauge of some type between the two
The summary requires at least 18 inches of horizontal or vertical pipe between filter and heater, or dedicated suction and return lines, or built-in connections for future solar. A gauge, valves or a direct flange do not meet it.2025 Energy Code §110.4(b)2
Where does one city's checklist require the gas shutoff for a pool heater?
- a.At the street meter alone
- b.Inside the house wall alone
- c.Within 6 feet of the heater✓
- d.Within 50 feet of the heater
The checklist requires a gas shut-off valve within 6 feet of the heater. Fifty feet, the street meter alone or an indoor valve are farther or not the local requirement.City of Dublin checklist (2025 CPC)
An air blower line for a spa is tied into the main recirculation return. What does the public-pool code say?
- a.Aeration and jets fully separate✓
- b.It is acceptable on residential spas
- c.It is acceptable if a check valve is added
- d.It is acceptable if the blower is quiet
A spa's aeration or jet system is completely separate from the recirculation system and not interconnected with any other pool. A check valve, a residential label and low noise do not change that.2025 CBC §3138B.1
Which circuit needs GFCI protection under one city's electrical summary?
- a.A 400-ampere service entrance for the house
- b.A wall clock in the pool bathroom
- c.A doorbell transformer at the front gate
- d.A 15- or 20-ampere pump motor circuit✓
Pool pump motors of that rating, cord-connected or hardwired, need GFCI protection. A service entrance, a clock and a doorbell are not pool pump circuits.City electrical handout (Menifee), 2022 CEC §680.21(C)
In a city using the 2022-code homeowner guide, how close may a pool receptacle be to the pool?
- a.No closer than 10 feet✓
- b.As close as 2 feet
- c.As close as 5 feet
- d.As close as 6 feet
That guide allows no receptacle closer than 10 feet and requires at least one GFCI receptacle between 10 and 20 feet. The 6-foot figure belongs to the county handout and the 2025 city checklist, and 2 and 5 feet are closer than any source allows.City builder guide (Menifee), 2022 CEC
A county handout requires a general-purpose receptacle at what distance from the inside pool wall?
- a.1 to 3 feet
- b.30 to 50 feet
- c.A single 10-foot point
- d.6 to 20 feet✓
The county handout calls for at least one general-purpose receptacle between 6 and 20 feet from the inside wall, GFCI protected. Distances of 1 to 3 feet are too close, 30 to 50 feet are too far, and a single 10-foot point restates one spot inside the range instead of the rule.County of Sonoma CNI-044
Which fixture does one city's pool guide prohibit?
- a.A fixture 20 feet high at 15 feet from the water
- b.A deck light 30 feet from the water at 10 feet high
- c.A luminaire 8 feet up, 4 feet from the edge✓
- d.A GFCI-protected wet-niche pool light installed per plan
The guide prohibits fixtures within 5 feet of the edge and less than 12 feet above grade, or directly over the pool, and the fixture 8 feet up and 4 feet from the edge breaks both limits. The fixtures 15 or 10 feet from the water lie outside the restricted zone, and the wet-niche light is the normal installation.City builder guide (Menifee)
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What clear working space does one city's guide require in front of electrical sub-panels?
- a.10 feet deep and 10 feet wide
- b.36 inches deep and 30 inches wide✓
- c.6 inches deep and 6 inches wide
- d.18 inches deep and 12 inches wide
The guide requires a clear space 36 inches deep and 30 inches wide, free of other objects. Ten feet by 10 feet is far more than the guide asks, and 6 by 6 inches and 18 by 12 inches are smaller than the required space.City builder guide (Menifee)
What is applied to the ground wire connection in a wet-niche forming shell before plastering, except for LED fixtures?
- a.Potting compound over the lug and wire✓
- b.Skipped sealing, since the lug is submerged
- c.Electrical tape wrapped around the lug
- d.Pool paint brushed over the lug
The guide requires the ground lug and wire connection to be covered or encapsulated with an approved potting compound. Tape and paint do not seal it against water, and a submerged lug is exactly why it needs sealing.City builder guide (Menifee)
How must pool equipment's electrical connections be made?
- a.To the listing and maker's instructions✓
- b.With unlisted adapters if they fit
- c.To the owner's stated preference
- d.With whatever fasteners are on the truck
Electrical equipment is installed according to its listing and manufacturer's instructions. Unlisted adapters, the owner's preference and whatever fasteners are on the truck all ignore the listing.City electrical handout (Menifee), 2022 CEC §110.3(B)
Which feature does the Energy Code require of pool heating equipment?
- a.A readily accessible on-off switch✓
- b.A continuously burning pilot light
- c.A built-in variable-speed pump
- d.A built-in debris skimmer
Heaters need an externally mounted, readily accessible on-off switch, and gas heaters may not have a continuously burning pilot. A pump and a skimmer are not heater features.2025 Energy Code §110.4(a), §110.5
Which control must a residential pool have under the Energy Code?
- a.A lifeguard call button on the deck
- b.A time switch for off-peak pump operation✓
- c.A wireless remote for the pool light
- d.A mechanical water-level float for the skimmer
The summary requires a permanently installed time switch so pumps run during off-peak electric demand periods, plus directional inlets. A lifeguard call button, a wireless light remote and a skimmer float are not Energy Code controls.2025 Energy Code §110.4(b)4
What must a public cartridge filter system provide for continuous service?
- a.A salt cell in the return line
- b.A separate blower for the cartridges
- c.A second heater on the same loop
- d.A second set of elements to swap in✓
The code requires an additional set of filter elements available while the existing elements are cleaned. A heater, salt cell and blower are not required for service.2025 CBC §3132B.3
What filtration rate cap applies to a public rapid sand pressure filter?
- a.15 gallons per minute per square foot
- b.0.375 gallons per minute per square foot
- c.3 gallons per minute per square foot✓
- d.30 gallons per minute per square foot
Rapid sand pressure filters are capped at 3 gpm per square foot. The 0.375 figure is cartridge, and 15 is the minimum backwash rate.2025 CBC §3129B.1
A public pool needs 240 gpm through a DE filter capped at 2 gpm per square foot. What minimum area is needed?
- a.80 square feet
- b.120 square feet✓
- c.12 square feet
- d.480 square feet
Area is 240 ÷ 2 = 120 square feet. Multiplying gives 480, the sand rate gives 80, and 12 divides by 20.2025 CBC §3130B.1
What must the floor of a public pool equipment area built since 2013 provide?
- a.A bed of loose gravel for drainage
- b.A 1/4-inch-per-foot slope to a drain✓
- c.A level surface without a drain
- d.A carpeted surface for sound control
The floor must be sloped at least 1/4 inch per foot to a drain and be a continuous slab of cleanable, nonabsorbent material. Loose gravel and carpet cannot be cleaned, and a level floor with no drain does not shed water.2025 CBC §3122B
Solar collectors are the compliance path for a pool with 600 square feet of surface. What is the minimum collector area?
- a.100 square feet
- b.240 square feet
- c.360 square feet✓
- d.600 square feet
Sixty percent of 600 is 360. The figure 240 is 40 percent, 600 is the full area, and 100 is not related.2025 Energy Code §110.4(c)
Which license classification includes installing solar heating equipment for a pool in its definition?
- a.C-35 Lathing and Plastering
- b.C-33 Painting and Decorating
- c.C-9 Drywall
- d.C-53 Swimming Pool✓
The C-53 definition says a swimming pool contractor constructs pools, spas or hot tubs, including installation of solar heating equipment. C-35 covers lathing and plastering, C-33 painting and decorating, and C-9 drywall.16 CCR §832.53
How far must solar suction outlets be from any inlet fitting on a public pool?
- a.At least 20 feet
- b.At least 50 feet
- c.At least 5 feet✓
- d.At least 1 foot
Solar heating system suction outlets are located no closer than 5 feet to any pool inlet fitting. One foot is closer than allowed, and 20 and 50 feet are more than stated.2025 CBC §3139B.1
What must a solar heating installation not do to a public pool's circulation?
- a.Increase the width of the deck around it
- b.Change the color of the water in the shell
- c.Interfere with turnover or pipe velocity✓
- d.Reduce the depth of the pool at the shallow end
The installation shall not interfere with the required turnover rate nor exceed the pipe flow velocities. Color, deck width and depth are unrelated.2025 CBC §3139B.1
Which plumbing provision prepares a pool for future solar heating?
- a.Dedicated lines or connections✓
- b.A second pump motor on the pad
- c.A thicker liner in the shell
- d.A wider deck around the pool
The Energy Code allows dedicated suction and return lines or built-in or built-up connections installed to allow future solar. A second pump motor, a thicker liner and a wider deck provide no connection for solar heating.2025 Energy Code §110.4(b)2
Which systems does the solar contractor classification cover?
- a.Thermal and photovoltaic solar systems✓
- b.Gas piping and venting for water heaters
- c.Landscape lighting and low-voltage controls
- d.Pool finishes and interior plastering
The C-46 definition covers installing, modifying, maintaining and repairing thermal and photovoltaic solar energy systems. Gas piping and venting, landscape lighting and pool finishes belong to other trades.16 CCR §832.46
A fiberglass pool shell has no steel to bond. What does the nonconductive-shell handout call for?
- a.Skipped bonding for the shell
- b.An 8 AWG bare copper perimeter conductor✓
- c.A conductor attached to the ladder alone
- d.A conductor laid loose inside the water
The perimeter conductor serves in place of the shell's steel grid. Skipping it, bonding only the ladder or laying a wire in the water does not form the perimeter bond.City bonding handout (Menifee), 2019 CEC §680.26
What does one city's checklist require for fiberglass pools before they are filled?
- a.Barriers and safety features in place✓
- b.The landscaping planted around the shell
- c.The heater installed and running
- d.The deck poured and finished
Fiberglass pools must have all barriers and safety features in place before filling with water. The deck, heater and landscaping do not control the fill.City of Dublin checklist
A factory-built spa, 3 feet deep, rests on a patio slab and uses a hard-wired heater circuit. What does one city's checklist say about permits?
- a.No permits, even for hardwiring
- b.A full engineered building permit and plan review
- c.A planning permit in place of the others
- d.No building permit, but an electrical permit✓
Prefabricated spas not exceeding 4 feet deep on the ground or a slab are exempt from the building permit, while non-plug-in electrical connections need a permit. No permits at all ignores the hardwiring, a full engineered building permit is not required for an exempt spa, and a planning permit does not replace the building or electrical permits.City of Dublin checklist (Municipal Code 7.28.310)
Which spa is exempt from the Swimming Pool Safety Act's requirements?
- a.A spa with a decorative fabric cover
- b.A spa installed in an apartment lobby
- c.A spa with a lightweight foam lid
- d.A spa with a locking ASTM F1346 cover✓
The Act exempts hot tubs or spas with locking safety covers complying with ASTM F1346. A decorative or foam cover is not a compliant locking cover, and an apartment spa is a different setting handled elsewhere.Health and Safety Code §115925
How does the Act define a swimming pool?
- a.A structure with water over 18 inches deep✓
- b.Structures that have diving boards
- c.A structure with water more than 6 feet deep
- d.In-ground concrete structures at homes
The definition includes in-ground and aboveground structures, hot tubs, spas, portable spas and nonportable wading pools over 18 inches deep. Diving boards do not define a pool, 6 feet is not the depth threshold, and limiting it to in-ground concrete structures leaves out aboveground pools and spas.Health and Safety Code §115921
A portable spa at a single-family home holds water 24 inches deep. How does the Swimming Pool Safety Act treat it?
- a.Covered only when the spa is set into the ground
- b.A swimming pool, since portable spas over 18 inches count✓
- c.Not covered, because spas count only above 36 inches of depth
- d.Not covered, because a portable spa is not a fixed structure
The Act defines a swimming pool as a structure for swimming or recreational bathing that holds water over 18 inches deep, and the definition names spas and portable spas, so 24 inches qualifies. Being portable does not exempt it because portable spas are named, the 36-inch figure is not in the Act, and the definition includes aboveground structures, so burying it is not required. The one spa exemption is a locking safety cover that meets ASTM F1346.Health and Safety Code §115921
A safety pool cover used as an Act feature must carry what label?
- a.One verifying ASTM F1346-23✓
- b.One naming the cover's fabric color
- c.One naming the pump it protects
- d.One naming the installer's license
The cover must be accompanied by a label verifying the ASTM International F1346-23 specification. A label naming the fabric color, the pump it protects or the installer's license does not verify safety performance.Health and Safety Code §115922(a)(3)
Where does one county require the control for an electrically operated safety cover?
- a.Inside the pool under the cover
- b.Under the deck near the pump
- c.At ground level beside the pool
- d.At least 60 inches above grade✓
The control is mounted at least 60 inches above grade or floor so children cannot reach it. A control inside the pool under the cover or under the deck near the pump is unusable, and one at ground level is within a child's reach.County of Sonoma CNI-044
A homeowner proposes a labeled safety cover plus a pool alarm as the two features. What does the Act say?
- a.The pair satisfies it with a battery alarm
- b.The pair does not satisfy the requirement✓
- c.The pair satisfies it for spas
- d.The pair satisfies the requirement as listed
The Act lists a safety pool cover and an alarm as a combination that does not satisfy the requirement. A battery alarm does not change that, spas get no special treatment for this pair, and the pair is not satisfactory as listed.Health and Safety Code §115922(b)
Which outdoor pool must have a cover under the Energy Code?
- a.An indoor pool without a heater
- b.A pool that has a slide as its extra
- c.A pool under 2 feet of depth
- d.One with an electric or gas heater✓
Outdoor pools or spas with electric or gas heaters need a cover. An unheated indoor pool, a pool with a slide and a shallow pool are not triggers.2025 Energy Code §110.4(b)3
How far must a public pool deck extend behind and beside a diving board or slide?
- a.The board footprint itself
- b.4 feet each side and at the rear✓
- c.1 foot beyond the board
- d.12 feet in each direction
The deck extends 4 feet on both sides and the rear of any diving board, fixed access device or slide. The board footprint itself and 1 foot beyond it are shorter than 4 feet, and 12 feet in each direction is farther than the code asks.2025 CBC §3114B.1
What guard rail height is required on a diving board more than 1 meter above the water?
- a.12 inches above the board
- b.A guard rail is waived
- c.60 inches above the board
- d.36 inches above the board✓
Boards and platforms over 1 meter above the water need guard rails on both sides 36 inches above the board. A 12-inch rail is too low, a 60-inch rail is higher than the code asks, and the rail is not waived above 1 meter.2025 CBC §3113B.2
A grotto and a raised rock waterfall are added to a residential design. What does one city require?
- a.A verbal approval from the inspector
- b.A change of the pool finish color
- c.The basic permit and no more
- d.Stamped and signed details✓
The guide requires stamped and signed construction details for slides, raised rock coping, grottos and similar additions. A verbal approval, a finish color change and the basic permit alone do not meet it.City builder guide (Menifee)
A self-contained spa has a listed safety cover. How does one city's checklist treat the barrier requirements for it?
- a.The spa needs a fence on three sides only
- b.The spa needs a barrier only at night
- c.The spa is exempt from the barrier requirements✓
- d.The spa needs the same fence as a swimming pool
A self-contained spa or hot tub equipped with a listed safety cover is exempted from the barrier requirements, and if no cover information is available the pool barrier rules apply. A full fence, a three-sided fence and a night-only barrier add requirements the checklist does not impose for a covered spa.City of Dublin checklist; Health and Safety Code §115925
In one city's checklist, what is verified at the final inspection together with working equipment?
- a.Equipment warranty cards mailed to the maker
- b.A cover storage rack beside the equipment
- c.An approved safety cover or other barrier✓
- d.A pool cover in the fabric color the owner chose
The final inspection lists an approved safety cover or other barrier installation, with all equipment operational. The cover's color, mailed warranty cards and a storage rack are not inspection items.City of Dublin checklist