Specifying Anti-Microbial Coatings for Healthcare Environments

A Wall Is Part of the Clinical Envelope

In a healthcare building, surfaces are not decoration; they are a controlled environment. Walls, corridors, and clinical-area finishes are touched constantly, cleaned aggressively, and surrounded by people for whom a surface that harbours microbial growth is a genuine risk. A finish that performs in an office — looks clean, wipes down occasionally — is the wrong specification for a ward. The clinical setting asks the coating to do work the eye never sees: resist the growth of bacteria and mould on its surface, and keep doing so through years of repeated, harsh cleaning.

Coralex Painters specifies and applies coating systems for institutional and healthcare buildings across Accra, and an anti-microbial specification is one of the most misunderstood requests in the trade. It is routinely treated as a product choice — “use the anti-microbial paint” — when it is in fact a performance specification that has to be matched to tested standards, to the cleaning regime, and to the durability the setting demands. Getting it right is a matter of specification, not of picking a tin with the right word on the label.

What “Anti-Microbial” Actually Has to Mean

The term is only useful if it is backed by a test. An anti-microbial coating is one whose surface inhibits the survival and growth of microorganisms — but a marketing claim and a measured performance are different things. Internationally, the antibacterial activity of a treated surface is measured by ISO 22196, which sets out how to quantify the reduction of bacteria on a coated surface against an untreated control under defined conditions. A coating specified for a clinical area should be able to demonstrate performance to that standard, not simply carry the word “anti-microbial” on its data sheet.

That distinction matters because the performance has to be designed in and has to last. An additive that delivers measured antibacterial activity when the film is new is only useful if that activity persists through the surface’s working life and through the cleaning it will receive. Specifying to ISO 22196 anchors the conversation to a tested figure rather than a claim — the starting point for a finish that does clinical work rather than merely looking the part.

Cleanability Is Half the Specification

An anti-microbial surface that cannot withstand clinical cleaning is a contradiction. Healthcare surfaces are cleaned frequently and with disinfectants that are chemically harsh by design, and a coating that chalks, softens, or breaks down under that regime fails on two counts at once: it loses its finish, and as the film degrades it becomes harder to clean and more able to harbour the very growth it was meant to resist. So the specification cannot stop at antibacterial performance; it has to pair that performance with a finish hard and washable enough to survive the disinfection it will live with.

This is why an anti-microbial coating is a system, not a product. The right additive performance has to sit on the right finish chemistry, on the right primer, on a substrate prepared to take it — each element chosen so that the clinical performance is delivered and maintained, not delivered once and then eroded by the first month of cleaning.

Preparation and Film Build Decide Whether It Performs

The cleanest clinical specification on paper still depends on the surface beneath it. Substrate preparation graded to ISO 8501 ensures the coating bonds to sound material, because a high-performance finish that delaminates is no finish at all — and a peeling edge in a clinical area is exactly the discontinuity that defeats an infection-control surface. Through application, dry-film thickness is verified to ISO 2808, because the coating delivers its rated performance and its cleanability only at its specified build. An anti-microbial system applied thin is an anti-microbial system that under-performs invisibly.

Healthcare buildings rarely close to be repainted, so this work is also sequenced around live clinical operations — phased by wing or floor, worked in agreed windows, with low-VOC systems chosen so areas return to service quickly. The specification and the delivery are inseparable: the right system, prepared and built correctly, applied without compromising the running of the building.

What to Specify, Not Just What to Buy

For an estate or infection-control lead commissioning a clinical repaint, the request should not be “an anti-microbial paint.” It should be a specification: a system whose antibacterial activity is demonstrable to ISO 22196; a finish hard and washable enough for the cleaning and disinfection regime of the area; a substrate prepared to ISO 8501; and a film build verified to ISO 2808 so the rated performance is actually installed. And it should come with a documented record per area, so the estate can prove what was specified, maintain it, and reorder it to match.

That is the difference between a corridor that has been painted a clinical colour and a surface that is genuinely part of the infection-control envelope. Coralex Painters specifies anti-microbial systems to the standard the clinical setting requires, applies them to a prepared and verified substrate, and documents the result — because in a hospital, a finish that only looks hygienic is not hygienic at all.