Arizona ROC A (KA) Dual Engineering Examination

Under NEC Article 680, what is the minimum size of solid copper conductor required to form the equipotential bonding grid around an outdoor permanently installed swimming pool?

• A#8 AWG solid copper
• B#6 AWG stranded copper
• C#10 AWG solid copper
• D#4 AWG aluminum

According to the Virginia Graeme Baker (VGB) Pool and Spa Safety Act and ISPSC standards, what is the required configuration for submerged suction outlets in a commercial swimming pool?

• AA single main drain cover with an automatic shut-off pump relay
• BAt least two anti-entrapment suction outlets separated by a minimum of 3 feet on center
• CDual main drains spaced a maximum of 12 inches apart connected to a common header
• DA single unvented gravity suction sump with a flat grate cover

What are the maximum allowable water turnover times for a public commercial swimming pool and a public spa, respectively, per ISPSC standards?

• A12 hours for a pool and 2 hours for a spa
• B8 hours for a pool and 1 hour for a spa
• C6 hours for a pool and 30 minutes for a spa
• D4 hours for a pool and 15 minutes for a spa

What is the NEC Article 680 restriction regarding convenience electrical receptacles installed near an outdoor swimming pool wall?

• AReceptacles may be installed 3 feet from the pool wall if hardwired with #12 AWG copper
• BReceptacles are permitted anywhere along the coping provided they have weatherproof covers
• CAt least one GFCI-protected receptacle must be located between 6 feet and 20 feet from th…
• DNo receptacles are permitted within 20 feet of the inside pool wall under any condition

What is the primary engineering purpose of installing a hydrostatic relief valve in the floor sump of an in-ground concrete swimming pool?

• ATo equalize external hydrostatic groundwater pressure under the shell and prevent pool fl…
• BTo relieve internal hydraulic pressure generated by high-head filtration pumps
• CTo purge trapped air pockets from the main suction line during pump priming
• DTo automatically drain overflow water when rainwater exceeds the pool skimmer level

What ventilation feature is required for dedicated chemical storage rooms housing elemental chlorine gas cylinders for commercial pool treatment?

• ANatural gravity roof louvers only
• BContinuous mechanical exhaust ventilation with intake near the ceiling and exhaust taking…
• CHigh-velocity ceiling exhaust fans pulling air upward toward the roof deck
• DPositive-pressure supply fans blowing outside air into the room without exhaust ducting

What is the minimum 28-day compressive strength required for pneumatically applied concrete (shotcrete/gunite) forming a structural pool shell?

• A2,500 psi
• B3,000 psi
• C4,000 psi
• D5,500 psi

A rectangular commercial swimming pool measures 50 feet long by 24 feet wide. The shallow end is 3 feet deep for a length of 20 feet, sloping uniformly over 20 feet to a deep end depth of 9 feet for the remaining 10 feet. What is the approximate pool volume in gallons, and what flow rate (GPM) is required for a 6-hour turnover?

• A31,200 gallons and 87 GPM
• B36,000 gallons and 100 GPM
• C48,500 gallons and 135 GPM
• D58,000 gallons and 161 GPM

When connecting a commercial landscape irrigation system containing chemical fertigation injectors to a potable water supply, which backflow assembly is mandatory?

• AReduced Pressure Zone (RPZ) backflow preventer assembly
• BDouble Check Valve Assembly (DCVA)
• CAtmospheric Vacuum Breaker (AVB) installed at grade level
• DSingle check valve with a bypass meter

In commercial turf irrigation design, what does the principle of 'head-to-head coverage' require?

• ASprinkler heads should be spaced so each head throws water 25% of the distance to adjacen…
• BSprinkler heads must be placed such that the spray radius of each head reaches the locati…
• CSprinklers are spaced at twice the manufacturer's rated throw radius
• DSprinklers should alternate between full-circle and half-circle heads on the same lateral…

What is the standard base course depth and bedding sand layer thickness for an interlocking concrete paver pedestrian plaza per ICPI standards?

• A2 inches of uncompacted soil base and 2 inches of bedding sand
• B10 inches of asphalt millings base and 1/2 inch of damp coarse sand
• C4 to 6 inches of compacted dense-graded aggregate base and 1 inch of uncompacted bedding…
• D8 inches of concrete slurry sand base and 3 inches of compacted masonry sand

Without a custom site-specific structural engineering design, what is the maximum total exposed height generally permitted for standard gravity segmental concrete block retaining walls?

• A2 feet
• B3 feet
• C6 feet
• D4 feet (including buried base block)

What is the maximum recommended water flow velocity in thermoplastic (PVC) irrigation mainlines to prevent destructive water hammer surges?

• A5 feet per second (fps)
• B8 feet per second (fps)
• C12 feet per second (fps)
• D15 feet per second (fps)

For a 12V AC low-voltage landscape lighting system, what is the maximum recommended allowable voltage drop from the transformer to the furthest fixture?

• A25% of rated voltage (down to 9.0V)
• B10% of rated voltage (down to 10.8V)
• C2% of rated voltage (down to 11.76V)
• D40% of rated voltage (down to 7.2V)

If an automatic irrigation zone valve fails to shut off after the controller cycle finishes, which condition is the most probable physical cause?

• AA blown 2-amp controller fuse
• BA short circuit in the 24VAC solenoid coil
• CDebris trapped under the valve diaphragm seating surface or clogged bleed port
• DExcessive water pressure at the main meter exceeding 150 psi

How should a perforated subdrainage collector pipe be installed behind a masonry retaining wall to manage groundwater buildup?

• APlaced at the top of the wall backfill with perforation holes facing upward
• BEmbedded in fine clay backfill without filter fabric
• CPlaced on a smooth concrete cap above the high-water line
• DPlaced near the footing behind the wall with perforations facing down, surrounded by wash…

What is the minimum uniform slope required for a 4-inch gravity sanitary sewer lateral pipe to maintain a self-cleansing flow velocity of 2 feet per second?

• A1/4 inch per foot (2.08%)
• B1/8 inch per foot (1.04%)
• C1/16 inch per foot (0.52%)
• D1/2 inch per foot (4.16%)

When performing a low-pressure air test on a newly installed PVC gravity sewer line per ASTM F1417, how must groundwater above the pipe invert be accounted for?

• AAir testing cannot be performed if groundwater is present
• BThe test pressure must be increased by 0.433 psi for every foot of groundwater head above…
• CGroundwater requires subtracting 1.0 psi from the standard 3.5 psi test pressure
• DThe air pressure must be held at 25 psi regardless of water table height

In sanitary sewer manhole construction, at what vertical elevation difference between the incoming sewer invert and the manhole bench is an external drop manhole connection required?

• A12 inches or greater
• B18 inches or greater
• C24 inches or greater
• D36 inches or greater

Which pipe bedding class provides the highest structural load capacity for rigid concrete sewer pipe by encasing the pipe bottom in reinforced concrete?

• AClass D bedding
• BClass C bedding
• CClass B bedding
• DClass A concrete cradle bedding

Using Manning's equation for full-pipe flow, V = (1.486 / n) x R^(2/3) x S^(1/2), what is the approximate flow velocity in a 12-inch (1.0 ft) diameter smooth PVC sewer pipe (n = 0.010) laid at a slope of S = 0.0018 ft/ft? (Hydraulic radius R = D/4 = 0.25 ft.)

• A2.50 feet per second
• B3.73 feet per second
• C1.10 feet per second
• D5.20 feet per second

What is the maximum allowable distance between manholes on straight runs of public gravity sewer mains 15 inches in diameter or smaller?

• A250 feet
• B400 feet
• C600 feet
• D1,000 feet

When testing flexible thermoplastic (PVC) gravity sewer pipe for post-installation deflection using a rigid mandrel (go/no-go gauge), what is the maximum allowable pipe deflection?

• A1.0 percent of nominal internal diameter
• B3.0 percent of nominal internal diameter
• C5.0 percent of nominal internal diameter
• D12.0 percent of nominal internal diameter

How should initial backfill within the pipe embedment zone (haunching and side zone) of a flexible sewer pipe be placed and compacted?

• ADumped in a single 3-foot lift and compacted with a heavy vibratory sheepfoot roller
• BFlooded with water without mechanical compaction
• CPoured as loose soil up to finished grade
• DPlaced in uniform 6-inch loose lifts and hand-tamped or mechanically compacted to 95% Sta…

A commercial kitchen features fixtures total 30 drainage fixture units (DFUs). Per Uniform Plumbing Code (UPC) sizing tables for gravity grease interceptors, what is the minimum liquid capacity required?

• A750 gallons
• B250 gallons
• C1,500 gallons
• D3,000 gallons

Prior to installing a Cured-In-Place Pipe (CIPP) liner inside a deteriorated gravity sewer main, what preparatory step is required?

• ABackfilling the existing pipe with flowable concrete grout
• BHigh-pressure hydro-jetting cleanout and closed-circuit television (CCTV) inspection to c…
• CBoring a parallel bypass tunnel under the existing pipe alignment
• DHeating the host pipe to 300°F using steam torches

What is the standard hydrostatic test pressure and duration for newly constructed underground ductile iron or PVC water mains per AWWA standards?

• A50 psi held for 30 minutes
• B100 psi held for 1 hour
• C150 psi (or 1.5 times the working pressure) held for a minimum of 2 hours
• D300 psi held for 24 hours

Under AWWA C651, what is the required initial free chlorine concentration and minimum retention period for the continuous feed method of disinfecting a new water main?

• A10 mg/L chlorine for 4 hours
• B25 mg/L chlorine for 12 hours
• C100 mg/L chlorine for 1 hour
• D25 mg/L chlorine for 24 hours with at least 10 mg/L free chlorine residual remaining

Calculate the minimum required bearing area (sq ft) for a concrete thrust block at a 90-degree bend on an 8-inch water main tested at 150 psi. Resultant thrust F = 2 x P x A x sin(angle / 2). Assume an allowable soil bearing capacity of 1,500 lbs/sq ft and a pipe internal area A = 50.27 sq in.

• A7.1 square feet
• B4.2 square feet
• C12.5 square feet
• D18.8 square feet

What is the minimum horizontal separation required between a parallel potable water main and a sanitary sewer pipe per ADEQ / civil engineering utility rules?

• A3 feet horizontal clearance
• B10 feet horizontal clearance
• C15 feet horizontal clearance
• D25 feet horizontal clearance

Which backflow prevention assembly provides protection against both back-siphonage and backpressure in high-hazard commercial water service connections?

• ADual check valve without atmospheric vent
• BPressure Vacuum Breaker (PVB)
• CReduced Pressure Zone (RPZ) backflow assembly
• DAtmospheric Vacuum Breaker (AVB)

In corrosive soil conditions common in Arizona, how is underground ductile iron water pipe protected from exterior galvanic corrosion per AWWA C105?

• AApplying a thick coat of asphalt roof cement on site
• BWrapping the pipe in 1/4-inch lead sheeting
• CEncasement in loose polyethylene tubing (polywrap) secured with approved adhesive tape
• DSubmerging the pipe in sand without metallic bonding

What is the standard minimum depth of cover over potable water mains in Arizona to protect against surface traffic loads and extreme desert thermal stress?

• A36 to 48 inches
• B12 to 18 inches
• C60 to 72 inches
• D18 to 24 inches

Under the International Fuel Gas Code (IFGC) and NFPA 54, what is required when installing underground nonmetallic (polyethylene) fuel gas piping?

• AEncasing the pipe in steel conduit along its entire length
• BInstalling an insulated yellow copper tracer wire (minimum 18 AWG) alongside the pipe wit…
• CPainting the PE pipe with reflective yellow epoxy spray
• DPlacing steel rebar directly above the pipe every 5 feet

What are the minimum test pressure and duration requirements for testing a newly installed fuel gas piping system before placing it in service per IFGC?

• A100 psi for 2 hours
• B50 psi for 30 minutes
• C1.5 times the maximum working pressure, but not less than 3 psi, held for a minimum of 10…
• D10 psi for 5 seconds

A natural gas appliance requires an input rating of 250,000 BTU/hr (approx. 238 CFH for 1,050 BTU/cu ft gas). The pipe run from the meter regulator is 80 feet using Schedule 40 metallic pipe at 0.5 psi inlet pressure and 0.5-inch w.c. pressure drop. What minimum nominal pipe size is required per IFGC gas capacity tables?

• A1/2 inch
• B3/4 inch
• C1 inch
• D1-1/4 inch

What is the IFGC minimum depth of cover for underground fuel gas piping installed outdoors in soil?

• A12 inches below grade, reduced to 8 inches for approved individual outdoor appliance lines
• B6 inches
• C36 inches
• D48 inches

When purging air from a newly installed 2-inch commercial gas main prior to light-off, where must the purge discharge point be directed per NFPA 54?

• AInto the boiler room near the main burner ignition pilot
• BDirectly outdoors, clear of building air intakes, doors, windows, and ignition sources
• CInto an enclosed return air plenum
• DInto a sealed plastic containment drum filled with water

Which joining method is legally mandated for joining underground polyethylene (PE) gas pipe sections per IFGC Section 403?

• ASolvent cement welding
• BThreaded female couplings with Teflon tape
• CHeat fusion (butt fusion, socket fusion, or electrofusion) or approved mechanical fittings
• DLead-sweated sleeve joints

What is the minimum clearance distance required between an outdoor gas pressure regulator vent terminal and any building opening (windows, doors, or appliance intake vents)?

• A1 foot
• B2 feet
• C3 feet
• D10 feet

What is the minimum required design slope for built-up roofing (BUR) and single-ply roof membranes to ensure positive drainage per IBC Chapter 15?

• A1/4 inch per foot (2% slope)
• B1/8 inch per foot (1% slope)
• C1/2 inch per foot (4% slope)
• D1 inch per foot (8% slope)

When inspecting hot-air welded lap seams on a Thermoplastic Olefin (TPO) single-ply roof installation, how is seam integrity physically verified in the field?

• AX-ray radiation imaging of every linear foot
• BProbing cooled seams with a blunt cotter-pin probe or seam probe tool using firm hand pre…
• CFilling the roof surface with 6 inches of standing water for 72 hours
• DTorching seam edges with an open propane flame

For asphalt shingle roofs installed on low slopes between 2:12 and 4:12, what underlayment application is mandatory per IBC 1507.2?

• AA single layer of 15 lb felt applied with 2-inch overlaps
• BNo underlayment is required under asphalt shingles
• CTwo layers of ASTM D226 Type I (15 lb) underlayment felt applied in a shingle fashion ove…
• DA single sheet of 6-mil polyethylene plastic sheet taped at joints

At a vertical brick masonry chimney intersection on a steep-slope shingle roof, how should metal step flashing and counter-flashing be detailed?

• AContinuous single L-metal nailed to masonry faces
• BFlashing bedded entirely in exterior silicone caulk without mechanical fasteners
• CStep flashing strips woven between shingle courses with counter-flashing let into masonry…
• DAluminized roof coating brushed over bare brick

When reroofing an existing building, at what point does a structural evaluation of the roof deck and framing members become necessary before the new roof system is installed?

• AWhen the new roof system increases the total dead load of the roof by more than 5 percent
• BWhenever replacing damaged asphalt shingles on a residential roof
• COnly when changing shingle color from dark to light
• DWhen adding a second layer of 15 lb underlayment felt

How is wind uplift resistance increased along high-wind boundary zones (eaves, ridges, and corners) of a commercial standing seam metal roof?

• ADecreasing clip and fastener spacing along perimeter and corner zones
• BIncreasing panel width from 16 inches to 36 inches
• CEliminating perimeter edge cleats
• DApplying liquid roof coating along panel seams