Proactive Grooming Validation & Efficacy Across Coating Categories

Summary

As the IMO develops a legally binding Biofouling Management Convention, one assumption keeps coming up: that gentle brush grooming only suits certain antifouling coatings. This paper tests that assumption against more than 2,000 commercial cleans on 91 vessels over three years, covering hard, foul-release and ablative coatings. Across that dataset, no coating damage has been attributed to grooming.

The evidence goes beyond fleet data. Independent water sampling by SGS Marine Services during grooming of a self-polishing copolymer coating found copper and zinc below detection limits throughout. An ongoing submerged panel trial across seven leading coatings shows no significant change in dry film thickness at two-, four- or eight-week intervals.

The central finding is that coating risk is set by cleaning configuration and fouling load, not coating type. Slime forms within weeks on every coating, so grooming at that cadence keeps the required force within what every coating category tolerates. The paper argues that regulation should target outcomes, meaning clean hulls with intact coatings, rather than prescribing which coatings can be cleaned.