I85PREP
⌘ K
AMPP CCAS study materials
AMPP CCAS study resources

AMPP CCAS practice questions

One question at a time. Build your AMPP CCAS understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Surface Preparation

A specification requires white metal blast cleaning. Which standard defines this degree of surface cleanliness?

  1. SSPC-SP 7/NACE No. 4
  2. SSPC-SP 6/NACE No. 3
  3. SSPC-SP 5/NACE No. 1 Correct answer.
  4. SSPC-SP 10/NACE No. 2

Explanation

White metal blast cleaning is the most thorough abrasive blast grade; it requires removal of all visible rust, mill scale, coating, and foreign matter, leaving a uniform gray-white surface. It is published as SSPC-SP 5/NACE No. 1. The other designations describe progressively less thorough degrees of blast cleaning.

Question 2Surface Preparation

Loose rust, loose mill scale, and loose paint must be removed using only scrapers, wire brushes, and abrasive paper. Which standard covers this work?

  1. SSPC-SP 2 Correct answer.
  2. SSPC-SP 11
  3. SSPC-SP 15
  4. SSPC-SP 3

Explanation

Hand tool cleaning, covered by SSPC-SP 2, uses non-power hand tools such as scrapers, wire brushes, abrasive paper, and chipping hammers. It removes loose rust, loose mill scale, loose coating, and similar material but does not remove tightly adherent matter. Power-tool grades are separate standards.

Question 3Surface Preparation

Oil and grease must be removed from steel before abrasive blasting. Which SSPC standard describes this cleaning?

  1. SSPC-SP 13
  2. SSPC-SP 1 Correct answer.
  3. SSPC-SP 16
  4. SSPC-SP 8

Explanation

SSPC-SP 1 covers solvent cleaning: removal of oil, grease, dirt, soil, salts, and other contaminants using solvents, emulsions, alkaline cleaners, or steam. It is normally performed before blasting or power tooling so contamination is not driven into the steel or smeared across the surface.

Question 4Surface Preparation

Which field method measures the peak height of an abrasive blast profile on steel?

  1. A high-voltage holiday detector
  2. A magnetic pull-off gauge
  3. Replica tape Correct answer.
  4. A wet-film comb gauge

Explanation

Replica tape is a compressible foam pressed against the blasted surface so the peaks deform it; reading the tape with a spring micrometer gives profile peak height. Comparators per ISO 8503 give only a visual or tactile grade, not a numeric value.

Question 5Surface Preparation

Under the usual coating specification rule, how far above the dew point must the steel surface be before blasting or coating?

  1. At least 1°F (0.5°C) above the dew point
  2. At least 15°F (8°C) above the dew point
  3. At least 5°F (3°C) above the dew point Correct answer.
  4. Exactly at the dew point

Explanation

The widely applied rule is that steel temperature must be at least 5°F (3°C) above the dew point before abrasive blasting or coating. That margin prevents condensation from forming on the surface, which would contaminate the profile and impair adhesion.

Question 6Surface Preparation

At 7 a.m. the steel is 6°F above the dew point. By 9 a.m., rapid evaporative cooling has dropped the steel to 1°F below the dew point. What is the correct action?

  1. Heat the abrasive so it dries the steel as it blasts
  2. Stop work until steel is 5°F above the dew point Correct answer.
  3. Continue blasting; the abrasive scours off any moisture
  4. Continue blasting and apply a thin mist coat at once

Explanation

Once surface temperature reaches or falls below the dew point, moisture condenses on the steel and contaminates the freshly prepared profile, so both blasting and coating must stop. Work resumes only when the steel is again at least 5°F (3°C) above the dew point.

Question 7Surface Preparation

You must quantify chloride contamination on a blasted steel surface before coating. Which method is appropriate?

  1. Magnetic gauge measurement of profile
  2. Bresle patch extraction with conductivity reading Correct answer.
  3. High-voltage holiday detection
  4. Tape adhesion testing of the coating

Explanation

The Bresle method extracts soluble salts from a defined area using a patch and a known volume of water; conductivity of the recovered liquid is converted to salt density. It is described in ISO 8502-6 and ISO 8502-9 and is the usual field check for chlorides before coating.

Question 8Surface Preparation

Which test checks compressed blast air for entrained oil and water?

  1. ASTM D4285 blotter test Correct answer.
  2. ASTM D4417 surface profile test
  3. ASTM G62 holiday detection test
  4. ASTM D3359 tape adhesion test

Explanation

ASTM D4285 directs compressed air onto a white absorbent cloth for a specified period; oil or water in the air shows as staining or wetting of the cloth. Blasting with contaminated air can deposit oil on the fresh profile and cause coating defects such as fisheyes and poor adhesion.

Question 9Surface Preparation

What nozzle angle to the steel surface is recommended for abrasive blasting?

  1. Around 15 degrees
  2. Around 45 degrees
  3. Around 30 degrees
  4. Around 90 degrees Correct answer.

Explanation

The nozzle is held at roughly 75 to 90 degrees to the surface, which delivers maximum impact energy per particle. Lower angles reduce cleaning efficiency and tend to smear contamination rather than remove it.

Question 10Surface Preparation

A venturi nozzle has worn so the orifice has enlarged while compressor pressure stays the same. What is the result?

  1. Air consumption falls and profile deepens
  2. Air velocity rises and cleaning improves
  3. Air velocity falls and cleaning rate drops Correct answer.
  4. Air velocity holds steady but the pattern narrows

Explanation

A worn, enlarged orifice passes more air at lower velocity for the same compressor output, so impact energy per particle drops and cleaning rate falls while air consumption rises. Nozzles are replaced once the bore wears past a set limit, commonly about 1/16 inch.

Question 11Surface Preparation

Which abrasive characteristic most directly controls the depth of the anchor profile produced?

  1. Particle size of the abrasive Correct answer.
  2. Color of the abrasive
  3. Moisture content of the abrasive
  4. Bulk density of the abrasive

Explanation

Coarser particles carry more kinetic energy and produce a deeper, rougher profile, while finer abrasives give a shallower profile. Size and shape are therefore selected to match the specified profile and the thickness of the coating system.

Question 12Surface Preparation

Near-white blast cleaning (SSPC-SP 10/NACE No. 2) allows staining on no more than what percentage of each unit area?

  1. 5% Correct answer.
  2. 33%
  3. 0%
  4. 50%

Explanation

Near-white blast cleaning removes all visible rust, mill scale, coating, and foreign matter while allowing only slight staining or shadows on no more than 5% of each unit area. It sits between white metal, which allows no staining, and commercial blast, which allows up to 33%.

Question 13Surface Preparation

Commercial blast cleaning (SSPC-SP 6/NACE No. 3) is best described as which of the following?

  1. Removal of all visible matter, with no staining allowed anywhere
  2. Removal of all visible matter, with staining up to 33% allowed Correct answer.
  3. Removal of all visible matter, with staining up to 5% allowed
  4. Removal of loose matter only, with tight mill scale kept

Explanation

Commercial blast cleaning removes all visible rust, mill scale, coating, and foreign matter, but allows staining to remain on up to 33% of each unit area. It is the grade most often specified for coatings in atmospheric exposure.

Question 14Surface Preparation

In SSPC-SP 12/NACE No. 5, which water jetting level provides the most thorough cleaning?

  1. WJ-2
  2. WJ-4
  3. WJ-3
  4. WJ-1 Correct answer.

Explanation

WJ-1 is the most thorough water jetting level: it removes all visible coating, rust, and foreign matter down to bare substrate, permitting only faint shadows. WJ-2, WJ-3, and WJ-4 are progressively less thorough and are used where a lower cleanliness level is acceptable.

Question 15Surface Preparation

Why is dry silica sand restricted or banned as a blasting abrasive in many jurisdictions?

  1. It is too soft to cut a profile
  2. It cannot be recycled for reuse
  3. Breathing airborne silica causes silicosis Correct answer.
  4. It reacts with steel and causes corrosion

Explanation

Dry silica sand fractures on impact and releases respirable crystalline silica; inhaling it can cause silicosis and other lung disease, which is why many jurisdictions restrict or ban it. Where it is still permitted, engineering controls and respiratory protection are required.

Question 16Surface Preparation

New galvanized steel must be prepared for a thin-film coating without losing the zinc layer. Which method is appropriate?

  1. Pickling in a strong acid bath
  2. Sweep blasting with a fine non-metallic abrasive Correct answer.
  3. Power wire brushing until the zinc is removed
  4. Abrasive blasting to a 4 mil profile at full pressure

Explanation

Galvanized steel needs only a light, shallow anchor pattern to give the coating a mechanical key, which sweep blasting with a fine non-metallic abrasive at reduced pressure provides. Aggressive blasting cuts through the zinc and removes the sacrificial protection the coating relies on.

Question 17Surface Preparation

Which standard addresses surface preparation of concrete for coating?

  1. SSPC-SP 16/NACE No. 8
  2. SSPC-SP 8/NACE No. 9
  3. SSPC-SP 13/NACE No. 6 Correct answer.
  4. SSPC-SP 12/NACE No. 5

Explanation

SSPC-SP 13/NACE No. 6 covers preparation of concrete, including removal of laitance, curing compounds, and contaminants and creation of a profile by abrasive blasting, scarifying, or acid etching. Concrete differs from steel in being porous and brittle, so the techniques and acceptance criteria are different.

Question 18Surface Preparation

Why must tightly adherent mill scale be removed before a coating is applied for immersion service?

  1. It is porous and holds the coating poorly
  2. It contains salts that blister the coating
  3. It is anodic to steel and dissolves first
  4. It is cathodic to steel, so steel at breaks corrodes Correct answer.

Explanation

Mill scale is cathodic to the underlying steel, so at breaks or pores in the scale the exposed steel becomes anodic and corrodes locally, producing pitting beneath the coating. Scale is also brittle and can spall, carrying the coating with it.

Question 19Surface Preparation

How should sharp edges, weld spatter, and weld slag be handled before blasting and coating?

  1. Ground to a smooth radius and all spatter removed Correct answer.
  2. Covered with a thicker stripe of coating later
  3. Blasted at higher pressure to round them over
  4. Left as-is; coatings bridge edges without trouble

Explanation

Coatings pull away from sharp corners during curing, leaving thin spots and voids, and protruding spatter can poke through the film. Grinding edges to a small radius and removing slag and spatter before blasting gives a surface the coating can cover uniformly.

Question 20Surface Preparation

With a properly sized nozzle, raising blast pressure generally does what?

  1. Lowers cleaning rate and profile depth
  2. Raises cleaning rate but not profile depth
  3. Leaves cleaning rate unchanged but narrows the pattern
  4. Raises both cleaning rate and profile depth Correct answer.

Explanation

Higher blast pressure raises particle velocity, which increases both the cleaning rate and the depth of profile produced by a given abrasive. Excess pressure can warp thin steel or embed abrasive, so pressure is set according to the substrate and specification.

Question 21Surface Preparation

A steel surface shows pitting over its entire area and has rusted through the mill scale. Which ISO 8501-1 rust grade applies?

  1. Grade A
  2. Grade B
  3. Grade D Correct answer.
  4. Grade C

Explanation

Grade D describes steel that has rusted through its mill scale over the whole surface and shows general pitting. Grade A has largely intact mill scale with little or no rust, Grade B shows rust beginning, and Grade C has rust where mill scale has come away.

Question 22Surface Preparation

Recycled steel shot must be checked for oil, salt, and other contaminants that could be carried onto the steel. Which standard addresses this?

  1. SSPC-AB 3
  2. SSPC-AB 2 Correct answer.
  3. SSPC-AB 4
  4. SSPC-AB 1

Explanation

SSPC-AB 2 addresses the cleanliness of recycled ferrous metallic abrasives, requiring testing for contaminants that could be transferred to the substrate. New metallic abrasives are covered by SSPC-AB 3, mineral and slag abrasives by SSPC-AB 1, and encapsulated media by SSPC-AB 4.

Question 23Surface Preparation

An epoxy with a 3 mil dry film thickness is specified over a blast profile that measures 5 mils. What is the likely result?

  1. Coating peaks protrude through the film and rust early Correct answer.
  2. Adhesion improves because surface area is higher
  3. The coating cures faster on a deep profile
  4. No effect; profile does not influence performance

Explanation

When profile peak height exceeds the dry film thickness, the peaks can protrude through the coating and corrode, and the film over the peaks is too thin to protect the steel. The specified profile range is set to match the thickness of the coating system.

Question 24Surface Preparation

Adding water to the abrasive stream during blast cleaning primarily does what?

  1. Prevents all flash rust on the fresh profile
  2. Eliminates the need for respiratory protection
  3. Increases profile depth sharply
  4. Reduces dust and helps rinse away soluble salts Correct answer.

Explanation

Water in the blast stream suppresses airborne dust and can help rinse soluble salts from the surface, which is useful near sensitive areas. It does not remove the need for personal protective equipment, and corrosion inhibitors may be required to control flash rust.

Question 25Surface Preparation

A specification requires Sa 2½ in accordance with ISO 8501-1. Which SSPC/NACE grade is equivalent?

  1. SSPC-SP 6/NACE No. 3
  2. SSPC-SP 5/NACE No. 1
  3. SSPC-SP 10/NACE No. 2 Correct answer.
  4. SSPC-SP 7/NACE No. 4

Explanation

Sa 2½ is near-white blast cleaning, which corresponds to SSPC-SP 10/NACE No. 2. Sa 3 corresponds to white metal (SSPC-SP 5), Sa 2 to commercial blast (SSPC-SP 6), and Sa 1 to brush-off blast (SSPC-SP 7).

Question 26Surface Preparation

Which materials does solvent cleaning in accordance with SSPC-SP 1 primarily remove from a steel surface?

  1. Oil, grease, dirt, soil, and soluble salts Correct answer.
  2. Weld spatter and sharp edges
  3. Rust, mill scale, and old coatings
  4. Anchor profile and surface roughness

Explanation

SSPC-SP 1 solvent cleaning removes organic and soluble contaminants such as oil, grease, dirt, soil, and salts before mechanical surface preparation. It does not remove rust, mill scale, or existing coating films.

Question 27Surface Preparation

What is the primary function of the deadman switch on a blasting machine?

  1. To stop blast flow when the control is released Correct answer.
  2. To adjust nozzle angle during blasting operations
  3. To regulate the abrasive flow rate at the blast pot
  4. To measure compressed-air dew point at the compressor

Explanation

The deadman switch is a safety device that stops air and abrasive flow when the operator releases the control. This prevents uncontrolled blasting if the operator loses contact with the control.

Question 28Surface Preparation

Which surface preparation standard defines white metal blast cleaning?

  1. SSPC-SP 6/NACE No. 3
  2. SSPC-SP 7/NACE No. 4
  3. SSPC-SP 10/NACE No. 2
  4. SSPC-SP 5/NACE No. 1 Correct answer.

Explanation

SSPC-SP 5/NACE No. 1 is white metal blast cleaning, the most thorough abrasive blast cleaning grade. SSPC-SP 10 is near-white, SSPC-SP 6 is commercial, and SSPC-SP 7 is brush-off blast cleaning.

Question 29Surface Preparation

What is the ISO 8503 comparator used to assess?

  1. Oil content in compressed air
  2. Dew point margin at the steel surface
  3. Soluble salt concentration on the steel
  4. Surface profile grade after blasting Correct answer.

Explanation

ISO 8503 comparators are reference coupons used to judge the surface profile produced by grit or shot blasting. They help classify profile as fine, medium, or coarse and do not measure salts, oil, or dew point.

Question 30Surface Preparation

Which description matches power tool cleaning in accordance with SSPC-SP 3?

  1. Removal of all visible rust and mill scale to white metal
  2. Removal of soluble salts by high-pressure water jetting
  3. Removal of loose rust, mill scale, and paint by power tools Correct answer.
  4. Removal of only oil and grease by solvent wiping

Explanation

SSPC-SP 3 power tool cleaning removes loose rust, mill scale, paint, and other loosely adherent material using power tools. Tightly adherent material may remain, so it is not equivalent to white metal blast cleaning.

Question 31Surface Preparation

Why should carbon steel abrasives be kept separate from abrasives used to blast stainless steel?

  1. Carbon steel abrasive increases the stainless steel's chloride content
  2. Carbon steel abrasive is softer and cannot cut stainless steel
  3. Stainless steel requires only solvent cleaning and cannot be blasted
  4. Iron contamination can cause rust staining and localized corrosion Correct answer.

Explanation

Carbon steel abrasive can embed iron particles in stainless steel, and those particles can rust and initiate localized corrosion. Dedicated abrasives and equipment help prevent this cross-contamination.

Question 32Surface Preparation

Which method is commonly used to measure the peak-to-valley profile of a blasted steel surface in the field?

  1. Replica tape Correct answer.
  2. Pull-off adhesion tester
  3. Wet-film thickness gauge
  4. Bresle patch extraction

Explanation

Replica tape is pressed against the blasted surface, and the compressed tape is measured to determine surface profile. Bresle patches test salts, wet-film gauges measure coating thickness, and pull-off testers measure adhesion.

Question 33Surface Preparation

Brush-off blast cleaning in accordance with SSPC-SP 7/NACE No. 4 is typically specified to do what?

  1. Remove all mill scale and create a deep anchor profile
  2. Remove loose rust, loose scale, and loose paint Correct answer.
  3. Produce a white metal finish for immersion service
  4. Remove soluble salts to a conductivity limit

Explanation

SSPC-SP 7 is a light blast cleaning grade that removes loose rust, loose mill scale, loose paint, and other loose material. Tightly adherent material may remain, so it is not intended for severe immersion service.

Question 34Surface Preparation

Which pair of tests is commonly performed on concrete before coating to check substrate acceptability?

  1. Chloride content and blast nozzle size
  2. Surface temperature and abrasive mesh size
  3. Anchor profile and dew point
  4. Moisture vapor emission and pH Correct answer.

Explanation

Concrete moisture vapor emission and pH are commonly checked because excess moisture or high alkalinity can interfere with coating adhesion and curing. Surface profile is also important, but the paired tests listed here are moisture and pH.

Question 35Surface Preparation

What is a common symptom of moisture in the blast air or abrasive supply?

  1. A decrease in abrasive consumption
  2. A steady increase in nozzle pressure
  3. Surging or pulsating abrasive flow Correct answer.
  4. A finer, more uniform surface profile

Explanation

Moisture causes abrasive to clump and block or restrict flow, producing a surging or pulsating blast stream. It can also promote flash rusting on the prepared surface.

Question 36Surface Preparation

Why should blasting pressure be measured at the nozzle rather than only at the compressor gauge?

  1. Nozzle pressure measurement eliminates the need for a deadman switch
  2. Hose friction causes pressure loss before the nozzle Correct answer.
  3. Nozzle pressure is always higher than compressor pressure
  4. Compressor gauges cannot read above 100 psi

Explanation

Pressure drops due to friction and restrictions in the blast hose and fittings, so compressor gauge pressure does not equal pressure at the nozzle. Nozzle pressure is the meaningful value for blast performance.

Question 37Surface Preparation

Which practice is appropriate when abrasive blasting aluminum to avoid contamination?

  1. Use dedicated nonferrous abrasives and separate equipment Correct answer.
  2. Blast with silica sand only
  3. Skip blasting and apply coating over mill finish
  4. Use the same carbon steel grit used for structural steel

Explanation

Aluminum can be contaminated by iron or other embedded particles, so dedicated nonferrous abrasives and separate equipment are preferred. Carbon steel abrasives can leave rust-promoting contamination.

Question 38Surface Preparation

Which SSPC standard covers new ferrous metallic abrasives such as steel shot and grit?

  1. SSPC-AB 1
  2. SSPC-AB 2
  3. SSPC-AB 4
  4. SSPC-AB 3 Correct answer.

Explanation

SSPC-AB 3 specifies new ferrous metallic abrasives. SSPC-AB 1 covers mineral and slag abrasives, SSPC-AB 2 covers clean dry compressed air, and SSPC-AB 4 covers recycled ferrous metallic abrasives.

Question 39Surface Preparation

What is the main function of an abrasive reclaimer/separator in a closed-cycle blasting system?

  1. To remove fines, dust, and debris from reusable abrasive Correct answer.
  2. To measure surface profile
  3. To increase nozzle pressure
  4. To add moisture to the abrasive stream

Explanation

The reclaimer separates usable abrasive from dust, fines, and debris so that only sound abrasive returns to the blast stream. It does not pressurize the system or measure surface profile.

Question 40Surface Preparation

What is the primary reason for selecting an angular abrasive instead of a round abrasive for blast cleaning?

  1. Angular abrasive cuts and creates a sharper profile Correct answer.
  2. Angular abrasive is always less dusty
  3. Angular abrasive produces a peened surface without profile
  4. Angular abrasive removes the need to measure profile

Explanation

Angular abrasives cut into the steel and produce a sharper, more angular anchor profile, while round abrasives tend to peen the surface. Profile still must be measured and verified.

Question 41Coating Materials and Selection

Which generic coating type cures primarily by reaction of its binder with atmospheric moisture?

  1. Chlorinated rubber
  2. Thermoplastic acrylic
  3. Moisture-cured polyurethane Correct answer.
  4. Two-component epoxy polyamide

Explanation

Moisture-cured polyurethanes use isocyanate-functional prepolymers that react with water vapor to form urea linkages and a crosslinked film. The other systems rely on chemical addition, solvent release, or coalescence rather than consuming atmospheric moisture.

Question 42Coating Materials and Selection

Zinc dust in a zinc-rich primer protects steel mainly by:

  1. Surface wetting
  2. Sacrificial galvanic action Correct answer.
  3. Ultraviolet light absorption
  4. Film plasticization

Explanation

Zinc is anodic to steel in the galvanic series, so it corrodes preferentially and protects exposed steel at breaks in the film. The zinc corrosion products can also help block the coating and slow further attack.

Question 43Coating Materials and Selection

Which binder type is most susceptible to chalking and gloss loss during outdoor sunlight exposure?

  1. Epoxy Correct answer.
  2. Acrylic
  3. Fluoropolymer
  4. Polysiloxane

Explanation

Aromatic epoxy binders absorb ultraviolet energy and degrade at the surface, producing chalking and gloss loss. Acrylic, polysiloxane, and fluoropolymer binders are generally much more weather-resistant.

Question 44Coating Materials and Selection

Which service condition would make an alkyd coating a poor selection?

  1. Architectural trim
  2. Exterior wood siding
  3. Caustic immersion Correct answer.
  4. Interior steel handrails

Explanation

Alkyds cure by oxidative polymerization and can saponify or hydrolyze in alkaline environments. They are therefore unsuitable for caustic immersion, even though they are common on atmospheric architectural and wood surfaces.

Question 45Coating Materials and Selection

Inorganic zinc silicate primers develop their final film properties mainly through:

  1. Oxidation of unsaturated drying oils
  2. Solvent evaporation only
  3. Reaction with moisture in the air Correct answer.
  4. Coalescence of latex particles

Explanation

Inorganic zinc silicates cure by reacting with atmospheric moisture to form a rigid, heat-resistant silicate matrix. They do not depend on drying-oil oxidation or latex coalescence.

Question 46Coating Materials and Selection

Pot life of a two-component coating refers to the:

  1. Maximum allowed interval between coats
  2. Time needed to reach complete cure
  3. Usable time after components are mixed Correct answer.
  4. Time needed to prepare the substrate

Explanation

Pot life is the period after mixing during which a two-component coating remains workable and can still be applied properly. Once it is exceeded, viscosity rise or premature reaction can prevent proper film formation.

Question 47Coating Materials and Selection

A coating with 60% volume solids is applied at 150 micrometres wet film thickness. What dry film thickness should result if all solvent leaves the film?

  1. 250 micrometres
  2. 90 micrometres Correct answer.
  3. 60 micrometres
  4. 150 micrometres

Explanation

Dry film thickness is calculated as wet film thickness multiplied by volume solids: 150 micrometres times 0.60 equals 90 micrometres. The lost solvent accounts for the difference between wet and dry thickness.

Question 48Coating Materials and Selection

Which function is the primary role of a primer rather than a topcoat?

  1. Color stability
  2. Abrasion resistance
  3. Corrosion inhibition Correct answer.
  4. Gloss retention

Explanation

A primer is designed mainly to bond to the prepared substrate and inhibit corrosion, often with inhibitive pigments or zinc. Color, gloss, and abrasion resistance are more typical topcoat requirements.

Question 49Coating Materials and Selection

For an exterior steel structure in strong sunlight, which topcoat is generally preferred over a standard amine-cured epoxy?

  1. Coal tar epoxy
  2. Standard amine-cured epoxy
  3. Zinc-rich primer
  4. Aliphatic polyurethane Correct answer.

Explanation

Aliphatic polyurethane topcoats resist ultraviolet degradation and retain gloss and color much better than standard epoxies. Epoxies are useful as primers or intermediate coats but tend to chalk in sunlight.

Question 50Coating Materials and Selection

Which coating is most suitable for the interior of a tank storing hot, aggressive solvents?

  1. Acrylic latex
  2. Epoxy phenolic Correct answer.
  3. Alkyd enamel
  4. Inorganic zinc silicate

Explanation

Epoxy phenolic coatings have a high crosslink density and good resistance to many solvents and chemicals at elevated temperature. Latex and alkyd films are far too permeable and chemically vulnerable for this service.