AMPP CIP Level 2 key terms

A stage in the coating work that cannot proceed until the inspector has performed the specified check and recorded approval. Work stops here regardless of schedule pressure, so the check cannot be skipped.

A step in the inspection plan where the contractor notifies the inspector before covering up work, but production may continue if the inspector chooses not to attend the check.

A meeting held before coating work starts where owner, contractor, applicator, and inspector review the specification, inspection plan, access, safety arrangements, and lines of communication so expectations are aligned.

A formal document recording work that does not meet the specification, stating the condition found, its location, the requirement violated, and the disposition or corrective action required before the work can be accepted.

A record kept for each working day summarising weather, surface conditions, products and batch numbers used, tests performed with results, manpower on site, and any deviations or instructions observed during the job.

The project document that states the required surface preparation, coating products, dry film thicknesses, environmental limits, test methods, and acceptance criteria for each area to be coated.

A document listing the inspections and tests to be carried out on a job, who performs each one, the acceptance criteria, and which steps are designated as hold or witness points.

The temperature at which water vapour in the air begins to condense onto a cooler surface. Coating work generally requires the steel to be at least 3 degrees Celsius above this value.

The amount of water vapour in the air expressed as a percentage of the maximum the air could hold at that temperature. It affects drying, curing, and the risk of condensation forming on steel.

The roughness pattern left on steel by abrasive blasting or power tools, usually described as depth in mils or micrometres. It gives the coating a mechanical key for adhesion.

A reference disc or plate carrying patches of graded roughness that is placed against the blasted surface, or compared by touch and magnification, to estimate the profile depth achieved.

A preparation method in which compressed air or centrifugal wheels propel abrasive particles against the steel to remove mill scale, rust, and old coatings and to cut the required profile.

A blast cleaning standard that calls for a near-white finish, allowing only very light shadows, streaks, or discolouration on a surface that is otherwise free of oil, mill scale, rust, and old coating.

A set of photographic reference standards showing blasted steel at each cleanliness level, used on site to judge whether the prepared surface matches the standard named in the specification.

A hard, brittle oxide layer formed on hot-rolled steel as it cools. If left beneath a coating it can flake away and take the coating with it, so it is normally removed by blasting.

Contaminants such as chlorides and sulfates left on the surface after cleaning. In the presence of moisture they draw water through the film and cause osmotic blistering and premature failure.

A field measurement of chloride left on the prepared surface, using a swab, sleeve, or patch extraction with a conductivity or titration instrument, and compared with the specification's permitted level.

The thickness of a coating measured while it is still wet, usually with a comb gauge, to confirm during application that the applicator is building toward the required dry thickness.

The thickness of the cured coating measured with magnetic or eddy-current gauges and compared against the specification's minimum, maximum, and average requirements for each coat and the total system.

A test that locates pinholes and thin spots in a coating by moving a wet sponge or a high-voltage probe over the surface and watching for the electrical signal that marks a defect.

A test in which a dolly is bonded to the coating and pulled perpendicular to the surface until failure. The recorded force and failure mode show how well the coating grips the substrate.

The percentage of a coating's liquid volume that remains as dry film once the solvent has evaporated. It determines how much area a given quantity of product will cover.

The area a unit volume of coating should cover at a stated dry film thickness, calculated as 1604 divided by the volume solids percentage to give square feet per gallon at one mil.

A primer containing a high proportion of zinc dust in an inorganic or organic binder. It protects steel by sacrificial action and is normally the first coat of a multi-coat system.

A two-component coating formed by reacting an epoxy resin with a curing agent. It gives tough, chemically resistant films but chalks and yellows when exposed to sunlight.

A coating based on urethane chemistry, widely used as a topcoat because it keeps colour and gloss in sunlight. Many types are two-component and need accurate mixing and induction.

The usable time after a two-component coating is mixed during which it can still be applied properly. Once that time passes the material thickens and will not form a sound film.

The waiting period some two-component products require between mixing and application, allowing the chemical reaction to begin so the coating sprays and cures as the manufacturer intends.

A method that forces coating at high pressure through a small tip so it atomises without compressed air. It is fast and suits high-build products but needs correct tip and pressure selection.

Equipment that meters and mixes two-component coatings at the spray gun so material is mixed only as it is used, avoiding the waste and interruption caused by pot life limits.

An extra pass applied by brush or roller to edges, welds, corners, and bolt heads before the main spray pass, because these areas are difficult to cover evenly by spraying alone.

The time window within which the next coat may be applied and still bond properly. Too short risks trapped solvent; too long risks poor adhesion and may require abrading the surface.

An enclosed or poorly ventilated area such as a tank or cargo hold with limited entry and exit, requiring a permit, atmospheric testing, ventilation, and a standby attendant outside.

A respirator that delivers clean breathing air from an external source through a hose to the wearer, required for abrasive blasting and many spray operations in enclosed or poorly ventilated areas.

A document supplied by the coating manufacturer listing a product's hazards, safe handling and storage, required protective equipment, first aid measures, and spill and fire response information.

Loss of coating adhesion spreading from a deliberate holiday on cathodically protected steel, driven by the alkaline environment at the exposed metal. Resistant coatings keep the disbonded radius small.