CSLB C-54 Ceramic and Mosaic Tile (Trade Exam) — All Questions
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40 questions
A tile contractor will cut painted walls in a preschool built in 1972. Which federal rule applies?
- a.The asbestos NESHAP only
- b.No rule; it is not housing
- c.The EPA RRP rule✓
- d.Only the OSHA noise rule
The RRP rule covers renovations for pay in pre-1978 housing and child-occupied facilities such as preschools. It is tempting to think only homes are covered.40 CFR 745 Subpart E
What is the title of the EPA pamphlet renovators must give owners before pre-1978 renovation work?
- a.Renovate Right✓
- b.Lead-Safe Homes
- c.Protect Your Family
- d.Know Your Tile
The rule's pamphlet is Renovate Right: Important Lead Hazard Information for Families, Child Care Providers and Schools, delivered no more than 60 days before work.40 CFR 745.83-.84
When vacuuming floors after removing presumed-asbestos vinyl tile, what floor tool must the HEPA vacuum use?
- a.Any tool with a HEPA bag
- b.A rotating brush head
- c.A metal tool, no brush✓
- d.A carpet beater bar
Cal/OSHA requires HEPA vacuums with a disposable bag and a metal floor tool, no brush. A brush head is the tempting default, but the order specifies a metal floor tool with no brush.8 CCR 1529(g)(8)
On a construction site, what does Cal/OSHA require for combustible debris inside the building?
- a.Storage in an open pile
- b.Removal at project completion
- c.Burning on site daily
- d.Prompt removal✓
Combustible debris accumulated inside the building shall be removed promptly during construction. Waiting until completion is the tempting shortcut.8 CCR 1513(d)
A floor will receive 16 × 16 inch tile. What flatness does ANSI A108.02 require over 10 feet?
- a.3/8 inch
- b.1/4 inch
- c.1/2 inch
- d.1/8 inch✓
Tile with an edge 15 inches or longer requires 1/8 inch in 10 feet and 1/16 inch in 2 feet. 1/4 inch applies only to smaller tile.ANSI A108.02-4.1.4.3.1 via CTEF
Water dropped on a clean slab soaks in immediately. What does that indicate?
- a.A curing compound is present
- b.The slab needs acid etching
- c.The slab is too wet to tile
- d.It is receptive to mortar✓
Water that penetrates immediately indicates the concrete needs minimal preparation. Beading would suggest a sealer or curing compound.CTEF, bond breakers
Before pouring a self-leveling underlayment, what must be applied to the prepared surface?
- a.The SLU maker's primer✓
- b.Thin-set as a bonding layer
- c.A coat of sealer
- d.Water until it stands
SLUs require a properly prepared surface primed with the manufacturer's recommended product and allowed to dry. Standing water is a bond breaker.CTEF, SLU requirements
What thickness range do cement-based self-leveling underlayments cover, according to industry guidance?
- a.1 to 2 inches only
- b.Over 6 inches only
- c.1/16 inch to 6 inches✓
- d.1/4 to 1/2 inch only
Cement-based SLUs can be installed from as thin as 1/16 inch up to 6 inches, depending on the product.CTEF, underlayment guide
Under the TCNA stone method over wood (F250 STONE), what is the minimum plywood subfloor thickness?
- a.15/32 inch
- b.1/4 inch
- c.3/8 inch
- d.19/32 inch✓
F250 STONE calls for a tongue-and-groove plywood subfloor at least 19/32 inch thick, plus a second underlayment layer. 15/32 inch is the residential underlayment layer.TCNA F250 via CTEF
How are the joints between cementitious backer units treated under the VA specification?
- a.Fiberglass tape and mortar✓
- b.Left open for movement
- c.Paper tape and drywall mud
- d.Silicone sealant only
Joints and corners are filled with latex-portland cement mortar and covered with fiberglass tape embedded in the same mortar. Drywall mud is not a tile substrate treatment.VA 09 30 13
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What total thickness of scratch and leveling coats does the VA specification allow over solid backing?
- a.1/8 to 1/4 inch
- b.3/8 to 5/8 inch✓
- c.5/8 to 3/4 inch
- d.1 to 1-1/2 inches
Over solid backing the coats total 3/8 to 5/8 inch; over metal lath on studs, 5/8 to 3/4 inch.VA 09 30 13
In which three forms do waterproof membranes for tile come, according to industry guidance?
- a.Wax, oil and resin
- b.Liquid, fabric and sheet✓
- c.Paper, felt and foil
- d.Grout, caulk and paint
Waterproof membranes come as liquid-applied, fabric-reinforced and sheet products, each designed to bond, support tile and stop water.CTEF, wet areas
Under the VA liquid-membrane procedure, how far up the walls is the membrane turned?
- a.At least 1 inch
- b.Only to the cove joint
- c.At least 4 inches✓
- d.At least 12 inches
The membrane is extended over drain flashing rings and turned up vertical surfaces not less than 4 inches above the finish floor.VA 09 30 13
What nominal thickness does the federal specification give for a chlorinated-polyethylene crack isolation sheet?
- a.0.030 inch✓
- b.0.125 inch
- c.0.010 inch
- d.0.040 inch
The federal specification lists 0.030 inch for the CPE crack isolation membrane and 0.040 inch for the CPE shower waterproof membrane.UFGS 09 30 10
Under TCNA's residential exposure classes, which is an example of a Res3 (wet) surface?
- a.A dining room wainscot
- b.A dry hallway floor
- c.A tub-shower wall✓
- d.A fireplace hearth
Res3 includes shower floors and tub and shower walls: surfaces soaked or frequently wet. A hallway floor is not a wet surface.TCNA Handbook via CTEF
Paint overspray is found on a slab that will receive tile. Which removal approach does industry guidance reject?
- a.Photographing and reporting it
- b.Citrus or solvent cleaners✓
- c.A change order for the removal
- d.Mechanical removal after an RFI
Industry guidance says solvents and citrus cleaners should never be used because they drive the residue deeper. Reporting and a change order are the recommended path.CTEF, bond breakers
Who can remove the presumption that old resilient flooring and its mastic contain asbestos?
- a.The tile contractor, by visual inspection of the material
- b.The flooring dealer who sold the material
- c.An industrial hygienist, by recognized analysis✓
- d.The building owner, by written statement that it is safe
Section 1529 treats resilient flooring, mastic and backing as asbestos-containing unless an industrial hygienist determines otherwise by recognized analysis. Visual judgement, a dealer's word and an owner's statement are not analytical determinations.8 CCR 1529
After removing presumed asbestos-containing vinyl tile, which cleanup method is prohibited?
- a.Dry sweeping✓
- b.Wet wiping of the floor
- c.HEPA vacuuming with a metal floor tool
- d.Wetting the area during scraping of adhesive
Section 1529 prohibits dry sweeping for this work. Wet methods, a HEPA-filtered vacuum with a metal floor tool and no brush, and wet scraping of adhesive are the permitted practices.8 CCR 1529
Who must supervise Class II asbestos work, such as removing asbestos-containing floor tile?
- a.A competent person✓
- b.A certified lead renovator
- c.A C-22 contractor's apprentice
- d.A building inspector present for the day
Section 1529 requires all Class II work to be supervised by a competent person as defined in the section. A lead renovator is certified under a different federal rule, an apprentice has no defined supervisory qualification, and a building inspector does not run the work.8 CCR 1529
Under the Contractors State License Law, what amount of asbestos-containing material in asbestos-related work calls for a C-22 license or a qualifier who passed the asbestos certification exam?
- a.100 square feet or more✓
- b.10 square feet or more
- c.50 square feet or more
- d.1,000 square feet or more
The law bars a contractor from asbestos-related work involving 100 square feet or more of asbestos-containing surface area without that license or certification. The statute excepts vinyl asbestos floor materials from the certification-exam requirement, but Cal/OSHA work rules still apply to them. The smaller and larger figures are not the statutory line.Contractors License Law, B&P Code 7058 series (2026 Law Book)
Under the federal lead renovation rule, how much painted interior surface per room can be disturbed and still count as minor repair and maintenance?
- a.1 square foot or less
- b.20 square feet or less
- c.100 square feet or less
- d.6 square feet or less✓
The rule's minor-repair definition is 6 square feet or less per room indoors. 20 square feet is the exterior figure, while 1 and 100 square feet are not the rule's thresholds.40 CFR 745.83
A crew wants to toss broken tile from an upper window into a ground-level bin. Under Cal/OSHA's construction orders, when is that allowed?
- a.When the crew shouts a warning first and watches the drop zone for people
- b.After normal working hours when the site is empty
- c.When the bin is covered with plywood
- d.Only when the landing area is guarded by barricades or similar means✓
Section 1513 bars throwing waste, materials or tools from buildings to areas where employees may be unless the fall area is guarded. A shout, the hour of day or a covered bin does not keep people out of the drop zone.8 CCR 1513
Where should a crew place waste solvents and other flammable job-site wastes?
- a.In the regular debris pile until the end of the working shift
- b.In open buckets kept beside the saw
- c.In covered containers kept separate from normal debris✓
- d.In the dumpster along with the broken tile and other debris
Section 1513 calls for flammable or hazardous wastes to go in covered containers separate from normal debris. Mixing them in a debris pile, leaving them open, or putting them in the general dumpster defeats that separation.8 CCR 1513
Before saw cutting or breaking a slab-on-grade for a plumbing change, what should be verified?
- a.Whether it is a post-tension slab✓
- b.Whether the slab is more than 4 inches thick
- c.Whether the slab has a curing compound
- d.Whether the slab has radiant tubing
A city bathroom-remodel handout warns that cutting a tendon in a post-tension slab can be dangerous to life and costly to repair. Thickness, curing compound and tubing matter for other reasons but are not the hazard that handout flags.City of Milpitas bathroom-remodel handout (2025 codes)
In a bathroom tile remodel, the tub shows small chips before work starts. What does industry guidance advise?
- a.Photograph the defects and tell the owner in writing✓
- b.Say nothing, since the tub will be covered by a drop cloth
- c.Mention it to the owner in passing
- d.Repair the chips first with leftover thin-set mortar from the job
Guidance says to inspect the tub, take photos and report defects in writing, because an installer who starts without notice may end up paying to repair or replace the tub. Silence and a casual mention leave no record, and mortar is not a tub repair material.CTEF, tub protection
Before its employees arrive at a construction site, what must the employer do about site conditions?
- a.Order a safety inspection from the city building department
- b.Wait for the first injury report to show what the hazards are
- c.Make a thorough survey of the site for predictable hazards✓
- d.Hand out the Code of Safe Practices at the gate
Section 1511 requires a thorough survey of the site before employees are present to determine predictable hazards and the safeguards needed. No city inspection is required for this, waiting for an injury is the opposite of prevention, and handing out the Code does not identify site hazards.8 CCR 1511
The federal tile specification lists a floor tolerance for dry-set mortar installations. What is it?
- a.1/4 inch in 10 feet
- b.1/16 inch in 3 feet
- c.1/8 inch in 10 feet✓
- d.1/8 inch in 8 feet
For dry-set mortar floors the specification gives 1/8 inch in 10 feet. 1/4 inch in 10 feet is the VA allowance for a portland cement mortar bed, 1/16 inch in 3 feet is the organic adhesive floor figure, and 1/8 inch in 8 feet is the wall figure.UFGS 09 30 10
A floor slopes evenly 1 inch over 12 feet but has no high or low spots. In tile terms, it is:
- a.Level but not flat
- b.Flat but not level✓
- c.Both flat and level
- d.Neither flat nor level
In tile work, flat means no significant high or low spots, and level means parallel to a true horizontal plane. An even slope is flat and not level, so tile can sit on it without lippage.CTEF, flat vs level
What must grinding equipment be fitted with when preparing a substrate for tile?
- a.A water nozzle that wets the slab down with slurry
- b.A bonnet that sends dust to an approved HEPA vacuum✓
- c.A dry broom attachment that sweeps dust aside
- d.A cloth sleeve that holds the dust loosely
Industry guidance says grinders must have the appropriate bonnet to capture dust and send it to an attached, approved HEPA vacuum. A water nozzle only makes slurry, a broom attachment moves dust around, and a cloth sleeve does not filter fine dust.CTEF, substrate patching
A new slab has curing compound on it. Which preparation method does industry guidance say properly removes it?
- a.Mopping with a citrus-based cleaner and rinsing
- b.Mechanical abrasion such as shot blasting✓
- c.Wiping with paint remover
- d.Brushing on a bonding sealer
Guidance names mechanical abrasion, such as shot or bead blasting, as the proper way to take off a thin layer along with the compound. Citrus cleaners and paint removers should never be permitted, and a sealer would simply add another bond breaker.CTEF, bond breakers
How should water be measured when mixing a self-leveling underlayment?
- a.By eye against the bucket line
- b.By adding it until the mix looks pourable
- c.In a measuring container✓
- d.By the same count as the last bag mixed
Guidance says accurately measuring the water in a measuring container is a must for self-leveling underlayment. Judging by eye, by pourability or by the previous bag's count gives an inconsistent mix.CTEF, self-leveling underlayment
Before any tile installation begins, what must be determined about the structure?
- a.That the finished floor is the same color as the walls
- b.That the mortar supplier has a local warehouse
- c.That the tile carton count matches the order
- d.That it can carry the added weight of the tile assembly✓
Guidance says the ability of the structure to carry the added weight of the tile assembly must be determined first. Color matching, warehouse location and carton counts do not address what the framing can support.CTEF, underlayment guide
Which ASTM standard does the VA specification cite for polyethylene sheet used as a cleavage membrane?
- a.ASTM D4397✓
- b.ASTM C648
- c.ASTM C847
- d.ASTM C1026
The specification cites polyethylene sheet conforming to ASTM D4397. C648 is breaking strength of tile, C847 is metal lath, and C1026 is the freeze-thaw test for exterior tile.VA 09 30 13
Which of these is a requirement listed for a waterproof membrane under tile?
- a.It must absorb water into its fabric
- b.It must stay loose-laid under the mortar bed
- c.It must bond tenaciously to the protected surface✓
- d.It must add texture to the finished tile surface
Guidance lists bonding tenaciously to the protected surface, supporting the weight of the tile and preventing water from entering the substrate. Absorbing water defeats the purpose, a loose-laid layer cannot support tile, and texture is not a membrane requirement.CTEF, wet areas
What shear bond strength must an uncoupling membrane reach in seven days under the test cited for these products?
- a.50 psi or greater✓
- b.25 psi or greater
- c.100 psi or greater
- d.400 psi or greater
Uncoupling membranes are not covered by ANSI or ISO standards but must reach 50 psi or greater per the A118.12 test method. 25 psi is too low, and 100 and 400 psi are not the stated threshold (400 psi appears in guidance about glass tile bond).CTEF, underlayment guide
What tool helps an installer confirm the thickness of a liquid-applied waterproof membrane while it is still wet?
- a.A straightedge laid across the floor
- b.A wet film thickness gauge✓
- c.A moisture meter used on the slab
- d.A notched trowel
A wet film gauge reads the applied thickness before the coat cures. A straightedge checks flatness, a moisture meter checks substrate moisture, and a trowel does not measure film thickness.CTEF, wet areas
After the second coat, what total thickness does the VA specification give for a liquid-applied elastomeric membrane?
- a.5 to 8 mils
- b.10 to 20 mils
- c.100 to 150 mils
- d.50 to 75 mils✓
The first coat is 30 to 50 mils and the recoat brings the total to 50 to 75 mils (1.3 to 1.9 mm). The smaller ranges are far too thin, and 100 to 150 mils is double the stated total.VA 09 30 13
After a liquid-applied membrane cures, how does the VA specification test it for leaks?
- a.1/2 inch of water for 1 hour
- b.2 inches of water for 72 hours
- c.4 inches of water for 8 hours
- d.1 inch of water held for 24 hours✓
The VA test is 1 inch (25 mm) of water for 24 hours. The other depth and time pairs are not what that specification states.VA 09 30 13
Under the VA stone specification, how far must cleavage membrane be lapped at joints?
- a.At least 1 inch
- b.At least 2 inches
- c.At least 4 inches✓
- d.At least 12 inches
Cleavage membrane is placed over the substrate and lapped at least 100 mm (4 inches) at joints. 1 and 2 inches are too short to keep the bed separated, and 12 inches is more than the stated minimum.VA 09 63 40
An installer ties a loose-lay shower pan liner to an uncoupling membrane from a different maker, and it leaks. What does industry guidance say about this?
- a.Any two membranes are interchangeable with each other
- b.Mixed systems invite failure outside the warranty✓
- c.Leaks come only from poor tile cutting at the drain
- d.The manufacturer warranty will cover any mixed system
Guidance says combining products or methods from various manufacturers is a recipe for failure that the manufacturer's warranty will not cover, and its example of a pan liner joined to an uncoupling membrane leaked at once. Membranes are not interchangeable, and tile cutting was not the cause.CTEF, wet areas