Understanding the terminology behind industrial coatings helps facility managers, engineers, and maintenance professionals make better decisions about protecting critical assets. Whether you are evaluating a proposal, reviewing a coating specification, or planning a long-term maintenance strategy, knowing what these terms mean puts you in a stronger position to ask the right questions and get the right results.
This glossary covers the materials, methods, standards, and processes that define professional industrial coating work, from surface preparation and abrasive blasting through coating application, inspection, and long-term performance. Terms are organized by topic so you can quickly find what you need.
The ability of a coating to withstand mechanical wear from traffic, equipment, or material handling without degrading. High abrasion resistance is critical for floor coatings in manufacturing facilities and protective coatings on equipment subject to material flow or impact.
A surface preparation method that propels abrasive media at high velocity to remove rust, mill scale, old coatings, and contaminants from steel or concrete. Proper abrasive blasting creates the clean surface and anchor profile necessary for long-term coating adhesion and performance.
The bond strength between a coating and the substrate surface. Proper adhesion depends on surface cleanliness, preparation quality, environmental conditions during application, and compatibility between the coating and substrate material.
The surrounding air temperature at the time of coating application. Most coating systems specify minimum and maximum ambient temperature ranges for proper curing and film formation.
The professional organization formed by the merger of NACE International and SSPC that establishes coating application standards, inspector certifications, and contractor quality programs. AMPP standards govern surface preparation, coating application, and inspection across industrial projects.
A quality program certification for contractors performing coating work on industrial structures. QP1 certification verifies that a contractor maintains documented quality control procedures, trained personnel, proper equipment, and safety programs required for complex coating projects.
An advanced quality program certification specifically for contractors performing hazardous paint removal and abatement work. QP2 certification demonstrates capability to safely handle lead-based paint removal, chemical stripping, and other regulated coating removal activities with appropriate containment and disposal procedures.
The surface texture or roughness created by abrasive blasting, measured in mils. The anchor profile provides “tooth” for coating adhesion and is specified to match the coating system requirements, typically ranging from 1.5 to 4 mils for most industrial coatings.
An international standards organization that publishes technical standards for materials, products, and test methods, including numerous standards for coating materials, surface preparation, and performance testing used throughout industrial coating projects.
A protective coating system that isolates the substrate from the environment by forming an impermeable layer between the metal or concrete and corrosive elements such as moisture, oxygen, and chemicals.
A coating defect characterized by raised bubbles or pockets in the coating film, typically caused by moisture vapor transmission, solvent entrapment, or application over contaminated surfaces.
A primer or intermediate coating applied to improve adhesion between dissimilar materials or between old and new coating layers.
An electrochemical corrosion control method that protects metal structures by making them the cathode in an electrical circuit. Often used in conjunction with protective coatings on buried or submerged steel.
Surface degradation of a coating caused by UV exposure and weathering, resulting in a powdery residue. Common in exterior coatings and an indicator that recoating may be needed.
A coating’s ability to withstand exposure to acids, alkalis, solvents, and other aggressive chemicals without degrading, softening, or losing adhesion. Critical for coatings in processing plants, wastewater facilities, and chemical storage areas.
Protective coating systems for concrete or steel clarifier tanks in water and wastewater treatment plants, designed to resist continuous water immersion, pH fluctuations, and chemical exposure.
The complete specification of primer, intermediate coats, and topcoat layers designed to work together to provide required protection. Coating systems are engineered for specific environments and service conditions.
The internal strength of a coating film, the ability of the coating to hold together as a unified layer. Poor cohesion leads to coating failure even when adhesion to the substrate is good.
An enclosed or partially enclosed area with limited entry and exit points, poor ventilation, and potential atmospheric hazards. Coating work inside tanks, vessels, and silos requires confined space entry permits, air monitoring, ventilation, and rescue planning.
The electrochemical deterioration of metal caused by reaction with its environment. In industrial facilities, corrosion is accelerated by moisture, chemical exposure, temperature cycling, and airborne contaminants.
The period required for a coating to reach full hardness, chemical resistance, and mechanical properties after application. Cure times vary by coating chemistry, temperature, and humidity.
The process of removing moisture from air in an enclosed space to create suitable environmental conditions for coating application and cure. Often required for tank lining projects to prevent moisture-related coating defects.
The separation of coating layers from each other or from the substrate, typically caused by poor surface preparation, contamination, or moisture infiltration.
The temperature at which moisture in the air condenses into liquid water. Coating application requires the substrate temperature to be a minimum of 5 degrees F above dew point to prevent moisture contamination during application and cure.
The thickness of a cured coating measured in mils (thousandths of an inch). Proper DFT is critical to coating performance: insufficient thickness reduces protection while excessive thickness can cause cracking or premature failure.
Specialized coating systems for anaerobic digester tanks in wastewater treatment facilities, requiring resistance to methane, hydrogen sulfide, and other aggressive byproducts of biological treatment processes.
A high-performance coating based on epoxy resins, known for excellent adhesion, chemical resistance, and abrasion resistance. Epoxy coatings are widely used for tank linings, floor coatings, and protective coatings in industrial environments.
A chemical surface preparation method using acid solutions to clean and profile concrete or masonry surfaces prior to coating application.
Light surface oxidation that forms on freshly blasted steel when exposed to moisture before coating application. Flash rust must be removed or addressed before coating to ensure proper adhesion.
The waiting period between application of coating layers to allow solvents to evaporate. Proper flash time prevents solvent entrapment that can cause blistering or poor intercoat adhesion.
Horizontal and vertical steel members in buildings, platforms, and structures requiring protective coating to prevent atmospheric corrosion.
Coatings certified for direct or indirect contact with food products, meeting FDA and USDA requirements. Used for floors, walls, tanks, and equipment in food processing and beverage production facilities.
A corrosion protection method where steel is coated with zinc through hot-dip or electroplating processes. Coatings over galvanized steel require special surface preparation and compatible primers.
A coating formulated to be applied at greater thickness per coat (typically 10+ mils DFT) to reduce the number of coats needed and provide enhanced barrier protection.
A gap, void, or pinhole in a coating film where the substrate is exposed. Holidays are detected using electronic holiday detectors and must be repaired to prevent localized corrosion.
The amount of moisture in the air, expressed as relative humidity percentage. Coating application typically requires relative humidity below 85% to prevent moisture-related defects.
Continuous or frequent submersion in liquids, requiring specialized coating systems designed for constant contact with water, chemicals, or other fluids. Common in tank linings and secondary containment applications.
The systematic examination and documentation of surface preparation quality, coating application procedures, film thickness, and final coating condition to verify compliance with specifications and standards.
A fire-resistive coating that swells when exposed to heat, forming an insulating char layer that protects structural steel from fire damage.
Water-based coating systems using latex binders. While common in architectural applications, industrial environments typically require higher-performance epoxy, urethane, or other chemistries.
The regulated process of removing lead-based paint from industrial structures, requiring AMPP QP2 certification, containment systems, worker protection, and documented disposal procedures.
The blue-gray iron oxide layer formed on steel during hot rolling manufacturing processes. Mill scale must be completely removed by abrasive blasting before coating because it provides poor adhesion and can cause premature coating failure.
The movement of water vapor through concrete slabs, which can cause blistering and delamination of floor coatings. MVT testing and moisture mitigation are critical before applying concrete floor coating systems.
Inspection methods that evaluate coating or substrate condition without causing damage, including holiday detection, ultrasonic thickness measurement, and adhesion testing.
Certification from NSF International that a coating or lining material is safe for contact with potable water or food products. Required for tank linings in water treatment and food processing facilities.
The federal agency that establishes and enforces workplace safety regulations, including requirements for fall protection, confined space entry, respiratory protection, and hazardous material handling during coating projects.
Coating failure caused by water or moisture moving through the coating film toward soluble salts or contaminants on the substrate surface, creating pressure that lifts the coating.
The application of new coating layers over existing coatings. Successful overcoating requires compatibility testing, proper surface preparation, and verification that the existing coating is sound.
A fast-curing urethane coating offering rapid return to service, UV resistance, and good chemical resistance. Often used for concrete floor coatings in industrial facilities requiring minimal downtime.
A high-performance coating known for excellent chemical resistance, abrasion resistance, and UV stability. Urethane coatings are commonly used as topcoats over epoxy systems and as primary coatings for floors and tanks in demanding chemical environments.
Drinking water. Tank linings for potable water storage require NSF-approved coating materials and strict application procedures to ensure safety.
NSF-approved coating systems for interior surfaces of drinking water storage tanks, meeting strict safety standards for human consumption.
The first coat in a coating system, applied directly to the prepared substrate to provide adhesion, corrosion resistance, and a suitable base for subsequent coats.
Systematic procedures to verify that surface preparation, coating materials, application methods, environmental conditions, and film thickness meet project specifications throughout all phases of work.
The time period during which additional coating layers can be applied over a previous coat without special surface preparation. Outside the recoat window, surface abrasion or other preparation may be required for proper adhesion between coats.
Iron oxide formed by the corrosion of steel when exposed to moisture and oxygen. Rust must be completely removed before coating application to ensure proper adhesion and long-term performance.
A visual assessment scale (typically A, B, C, D) describing the extent of corrosion on steel surfaces before preparation. Used to specify appropriate surface preparation methods.
A coating that corrodes preferentially to protect the underlying substrate, typically containing zinc or aluminum particles. Sacrificial coatings provide galvanic protection even when damaged.
A coating defect where material runs or curtains during application due to excessive film thickness, improper thinning, or application on vertical or overhead surfaces.
A common term for abrasive blasting when sand is used as the abrasive media. Modern industrial projects typically use steel grit, aluminum oxide, or other media instead of sand due to silica health hazards.
Structures such as dike floors, sumps, and containment basins designed to capture spills and leaks from primary storage vessels. Secondary containment coatings must resist chemical exposure and provide leak-proof protection.
The expected duration that a properly applied coating system will provide adequate protection before requiring maintenance or replacement, typically ranging from 10 to 20+ years depending on environment and system design.
Protective and functional coatings for grain, cement, aggregate, and other bulk material storage silos, often requiring both interior and exterior protection against abrasion, moisture, and environmental exposure.
Specialized coating systems for industrial chimneys and exhaust stacks, requiring high-temperature resistance, UV stability, and often access by rope or aerial lift for surface preparation and application.
Chlorides, sulfates, and other water-soluble contaminants on steel surfaces that can cause osmotic blistering and coating failure. Testing and removal of soluble salts are critical before coating application, especially in coastal or industrial environments.
A surface preparation standard for removing oil, grease, and other soluble contaminants using solvents or cleaners. Typically performed before abrasive blasting.
Abrasive blasting to remove at least 95% of all visible contaminants, leaving only slight shadows or discoloration. Required for immersion service, severe corrosion environments, and high-performance coating systems.
Manual surface preparation using wire brushes, scrapers, and chipping hammers to remove loose rust and coatings. Provides minimal surface preparation suitable only for low-performance coating systems or maintenance touch-up.
Mechanical surface preparation using power wire brushes, grinders, or sanders. Better than hand tool cleaning but still inferior to abrasive blasting for most industrial applications.
Abrasive blasting to remove 100% of all visible contaminants, leaving a uniformly white-gray metal surface. The highest standard of surface cleanliness, typically specified for the most demanding service conditions.
Abrasive blasting to remove all oil, grease, dirt, rust, and coating except for tightly adhered residues. Minimum 2/3 of surface must show uniform metal color. Acceptable for many industrial coating systems.
The underlying surface being coated: steel, concrete, aluminum, or other material requiring protection.
All activities required to clean and condition a substrate before coating application, including contaminant removal, abrasive blasting or mechanical preparation, and profile creation. Proper surface preparation is the single most critical factor in coating performance.
A specialized protective coating system applied to the interior of storage tanks to prevent corrosion, contamination, and product loss. Tank linings must be selected based on stored product, temperature, and regulatory requirements.
The final coating layer in a system, providing color, gloss, UV resistance, and the primary barrier against environmental exposure.
Localized coating repair of holidays, damaged areas, or welds after the main coating application is complete.
Corrosion that occurs beneath an intact coating film, typically caused by inadequate surface preparation, moisture penetration, or coating disbondment. Dangerous because damage progresses hidden from view.
A coating’s ability to withstand ultraviolet light exposure without chalking, fading, or degrading. Critical for exterior and roof coating applications.
Organic chemicals that evaporate from coating materials during application and cure. VOC content is regulated by environmental agencies, and many industrial facilities require low-VOC or compliant coating systems.
Exterior and interior coating systems for elevated water storage tanks, requiring specific surface preparation, approved materials for potable water contact, and often performed by crews trained in high-access work.
The thickness of a coating immediately after application, before solvent evaporation and cure. WFT measurement allows applicators to verify that proper dry film thickness will be achieved.
A primer coating containing high levels of metallic zinc that provides galvanic (sacrificial) corrosion protection to steel substrates. Widely used as a first coat in multi-layer protective coating systems for structural steel in corrosive environments.