Nevada A-10E Pool Alteration and Repair Contractor Examination

In pool circulation design, what does turnover time measure?

• AThe time required to heat the pool 10 degrees Fahrenheit
• BThe period required to circulate a volume of water equal to the pool or spa capacity thro…
• CThe time between backwashes of a sand filter
• DThe life of the filter media before replacement

Under NAC 444.152, a Nevada public bathing or swimming facility recirculation system must recirculate, clarify, and disinfect the facility volume at least how often?

• AEvery 12 hours or less
• BEvery 8 hours or less
• CEvery 6 hours or less
• DOnce every 24 hours

NAC 444.484 requires circulation and filtration equipment on a Nevada public spa to recirculate the entire spa volume at least once every:

• A6 hours
• B2 hours
• C60 minutes
• D30 minutes

Which three filter types are the standard media options when replacing pool or spa filtration equipment?

• ASand, diatomaceous earth (DE), and cartridge
• BGravel, zeolite only, and reverse-osmosis membrane
• CBag, carbon, and ion-exchange resin
• DScreen, sock, and paper-roll

A sand filter on a hotel pool reads 10 psi when clean. When should the A-10E technician backwash?

• AWhen the gauge returns to 0 psi
• BOn a fixed 24-hour clock regardless of pressure
• CWhen operating pressure rises about 8 to 10 psi above the clean starting pressure
• DOnly when the water is visibly green

Before moving a multiport filter valve from FILTER to BACKWASH, the technician must first:

• AIncrease the heater thermostat to high
• BShut off the circulating pump
• COpen the main drain all the way and close all skimmers
• DAdd a full charge of DE to the skimmer

A 21,600-gallon commercial pool must turn over in 6 hours. What minimum recirculation flow is required?

• A36 gpm
• B48 gpm
• C60 gpm
• D90 gpm

NAC 444.152 requires which pair of gauges on a public recirculation system?

• AA temperature gauge on the heater only and a chlorine residual chart
• BA vacuum gauge on or immediately before the pump suction and a pressure gauge immediately…
• CTwo pressure gauges, both on the filter influent
• DA flow meter only; gauges are optional on commercial systems

Where is the pump hair-and-lint strainer installed in a typical pool recirculation train?

• AOn the heater outlet, after the heat exchanger
• BOn the pump suction, before the impeller
• COn the filter waste line only
• DAfter the chemical feeder

After backwashing a diatomaceous-earth (DE) filter, what additional step is required before returning the system to FILTER?

• AReplace the sand laterals
• BRecharge the grids with the manufacturer’s specified charge of fresh DE
• CFill the tank with muriatic acid
• DRemove the grids and discard them after every backwash

How is a cartridge filter cleaned when pressure rises about 8 to 10 psi above the clean reading?

• AMove the multiport to BACKWASH for two minutes
• BShut down the pump, open the tank, remove the cartridges, and hose them clean
• CAdd DE powder through the skimmer
• DReplace the sand and laterals

A 600-gallon commercial spa must turn over in 30 minutes. What minimum recirculation flow is required?

• A10 gpm
• B15 gpm
• C20 gpm
• D40 gpm

When replacing a pump on a commercial hotel pool versus a single-family backyard pool, which requirement is MOST likely to change?

• AThe need for a strainer basket on the pump suction
• BThe required turnover time and health-authority listing of the equipment
• CThe need to prime a self-priming pump after service
• DThe use of PVC unions at the pump for future service

Replacement pumps, filters, and chemical feeders on public aquatic facilities should be listed to which equipment standard?

• ANSF/ANSI 50
• BNSF/ANSI 61 only
• CASTM C150
• DAWWA C651

A replacement circulating pump must be selected primarily to:

• AMatch the horsepower sticker on the old motor regardless of flow
• BDeliver the required turnover flow at the system’s total dynamic head with clean filter m…
• CProduce the highest possible pressure at the filter gauge
• DRun only on the jet-booster circuit

Total dynamic head (TDH) used to size a replacement pool pump includes:

• AOnly the vertical lift from the waterline to the heater top
• BPipe friction, fittings, elevation change, and equipment losses through the strainer, fil…
• COnly the clean-filter pressure reading
• DOnly the vacuum reading at the pump

When replacing a dedicated-purpose inground pool filter pump after the federal efficiency deadline, the replacement unit generally must:

• ABe a single-speed motor if the old pump was single-speed
• BMeet the applicable U.S. Department of Energy dedicated-purpose pool pump efficiency stan…
• CBe an aboveground storable-spa pump regardless of the vessel
• DOmit a strainer so head loss is reduced

NAC 444.152 requires the recirculation pattern in a public pool to be:

• AOne hundred percent through the main drain
• BOne hundred percent through the skimmers or gutters
• CPartial flow through the main drain and the remainder through overflow gutters or skimmers
• DOne hundred percent through the waterfall feature pump

NAC 444.496 requires each public spa’s filter, recirculation, and chlorination systems to be:

• AShared with the adjacent swimming pool to save equipment-pad space
• BIndependent of any adjacent swimming pool or spa
• CServed only by the pool’s skimmer line
• DOperated only when the adjacent pool is closed

In a standard equipment sequence, where should a replacement gas or heat-pump pool heater be installed?

• AOn the pump suction, before the strainer
• BAfter the filter and before the chemical feeder, with flow/pressure proving so the heater…
• COn the backwash waste line
• DBetween the skimmer and the main drain tee

NAC 444.154 sets a maximum turnover cycle of 4 hours for which public vessel type?

• AA standard rectangular competition pool
• BAn activity pool
• CA residential backyard spa
• DA decorative yard pond with no public use

A wading pool constructed after November 1, 1988, at a Nevada public facility must have:

• AThe same recirculation system as the adjacent adult pool
• BA maximum 30-minute turnover and a separate circulation system
• CA 12-hour private-pool turnover
• DNo filter if the water is dumped daily

A rising filter-pressure gauge with falling return-flow most likely indicates:

• AA clean filter that is ready for more media
• BA loaded filter that needs backwashing or cartridge cleaning
• CA failed pressure gauge that should be ignored
• DA closed suction valve at the skimmer

A sand filter backwashes to a clear sight glass but pressure returns to the dirty reading within hours and the sand surface shows holes or mounds. The BEST next repair is:

• AAdd DE on top of the sand
• BReplace channeled or fouled sand media and inspect laterals
• CInstall a larger impeller without opening the tank
• DClose the main drain permanently

NAC 444.152 requires a public recirculation system to run whenever the facility is open and for at least how long after closing?

• A30 minutes
• B1 hour
• C3 hours
• D12 hours

The generally accepted operating pH range for a chlorinated swimming pool is:

• A5.0 to 5.6
• B6.0 to 6.4
• C7.2 to 7.8
• D8.8 to 9.4

A newly replaced copper heat exchanger fails within weeks and the pool water tests at pH 6.6 with low alkalinity. The MOST likely cause is:

• AExcessively high pH creating soft scale that protects copper
• BAggressive low-pH water dissolving the copper exchanger
• CA variable-speed pump running on a low filtration speed
• DToo much DE in a sand filter

The FIRST routine mechanical cleaning steps on a plaster pool before chemical adjustment are:

• ADrain the pool to the hydrostatic valve every visit
• BBrush walls and floor and vacuum settled debris
• CAcid-wash the entire shell
• DChip out the waterline tile

A commercial pool has widespread soft, etched plaster and exposed aggregate. Which repair is MOST appropriate?

• AA light acid wash only, with no further finish work
• BDrain, chip or grind to sound substrate, apply a bond coat, and replaster
• CPaint over the etched plaster without surface preparation
• DRaise pH to 9.0 and wait for the plaster to reharden

A sounding hammer on a plaster wall produces a hollow tone over several square feet. What does that indicate?

• AThe plaster is fully bonded and only needs brushing
• BDelamination; the loose plaster should be removed to a sound edge before a bonded repair
• CThe tile thinset is too rich
• DThe filter sand has channeled

Immediately after a traditional white-plaster application, the BEST start-up practice is:

• ALeave the shell empty for two weeks to air-cure
• BBegin filling at once with a continuous, soft fill and start controlled brushing and chem…
• CAcid-wash the fresh plaster the same day
• DFill only to the shallow-end floor for 10 days

Before completely emptying an in-ground pool for plaster or tile work, the contractor should first consider:

• AWhether hydrostatic groundwater can float or crack the empty shell
• BWhether the skimmer weir is NSF-listed
• CWhether the time clock is set to 24-hour operation
• DWhether the waterfall pump is a two-speed model

Compared with a residential backyard route, daily operation of a Nevada public pool MORE often requires:

• ANo chemical testing if the water looks clear
• BWritten operation records, automatic or closely managed disinfection, and health-authorit…
• CDraining the vessel every night
• DPainting the plaster each spring

In the Las Vegas Valley, filter backwash and pool drain water should normally be discharged to:

• AThe street gutter and storm drain
• BThe sanitary sewer through an approved clean-out, not a septic tank
• CAn adjacent landscaped swale that drains to the wash
• DThe spa overflow so the spa filter can recapture it

A public spa has 3.0 ppm free chlorine and 5.5 ppm total chlorine. Combined chlorine is 2.5 ppm and bathers complain of odor and eye burn. The BEST immediate chemical response is:

• ALower free chlorine to 0.2 ppm
• BPerform breakpoint chlorination (shock) and increase turnover/air-out, then retest
• CAdd cyanuric acid until combined chlorine disappears
• DTurn the heater up to 110 degrees Fahrenheit

Green, cloudy water with slippery walls MOST likely indicates:

• AAn algae bloom from inadequate sanitizer and poor circulation
• BToo much DE on a freshly charged filter
• CA failed hydrostatic relief valve
• DOver-compacted deck subgrade

An A-10E contractor servicing a hotel courtyard fountain that shares no piping with the swimming pool should treat the fountain’s recirculation as:

• AUnregulated decorative water that never needs filtration
• BIts own vessel with listed pumps, filters, and treatment sized to that feature’s volume a…
• CA branch of the pool skimmer line
• DA drainage-only system with no pump

In southern Nevada, year-round in-ground pool service MOST often means:

• AContinued circulation, water-level control, and chemistry, with freeze or wind protection…
• BA full freeze-up with the pool left empty all winter
• CRemoving the pump and burying the returns each October
• DConverting the pool to a sand filter dry well

A gas heater lights briefly then shuts down. The filter is clean, the pump is primed, but the heater’s pressure/flow switch barely makes. What is the BEST next check?

• AConfirm isolation valves are open, the internal heater bypass is set, and residual filter…
• BRaise the spa set point to 120 degrees Fahrenheit
• CAdd two bags of salt to the skimmer
• DRemove the bonding lug from the heater jacket

After a site-wide power outage, NAC 444.152 requires time clocks that govern a public recirculation system to be:

• AReset immediately, including any dependent disinfectant feeders, slurry feeders, or heate…
• BLeft as found so the original program is preserved
• CDisconnected permanently in favor of manual-only operation
• DSet to run the heater with the pump off to catch up on temperature

Why must operating water level be held at the mid-skimmer or gutter lip?

• ASo the overflow system can skim the surface and the pump does not pull air
• BTo hide stained waterline tile
• CTo increase hydrostatic uplift under the floor
• DTo keep the heater pressure switch from closing

Why do commercial spas typically need more frequent drain-and-refill than residential spas of similar volume?

• AHigher bather load concentrates oils, combined chlorine, and total dissolved solids faster
• BCommercial spas are exempt from turnover rules
• CResidential spas use more sanitizer by law
• DCommercial spas cannot be filtered

A replacement pump rattles, the gauge needles bounce, and air bubbles exit the returns. The strainer lid is dry on top. What is the MOST likely cause?

• AA suction-side air leak at the lid O-ring, unions, or valves
• BA filter that is too large for the pump
• CToo much DE on the grids
• DA closed return valve only

When is pool painting a reasonable alternative to replastering?

• AWhen the existing cementitious finish is sound, clean, dry, and prepared to the coating m…
• BWhen large hollow delaminated areas are left in place to save labor
• CWhen the shell is actively leaking at construction joints
• DWhen the owner wants to skip surface preparation

A skimmer that starves the pump even though the waterline is correct MOST often needs:

• AA cleaned or replaced basket, weir, and equalizer or float-valve check
• BA larger gas heater
• CThe main drain capped
• DThe filter multiport left on RECIRCULATE permanently

Which statement correctly distinguishes Nevada A-10E from A-10C?

• AA-10E authorizes alteration and repair of plaster, tile, coping, pumps, filters, heaters,…
• BA-10E is limited to residential plaster, coping, and deck coatings only
• CA-10C authorizes commercial pump and heater replacement
• DA-10E is a plumbing-only classification for water and gas service lines