A ship’s hull is one of its most critical components, providing buoyancy, structural integrity, and housing for essential machinery including engines, generators, and fuel systems. Because vessels spend an estimated 94% of their lives on water, hulls face constant exposure to corrosion, biofouling, and harsh sea conditions — making regular maintenance essential to performance and safety. Hull cleaning is typically required every 6 to 12 months, with mandatory drydocking at least twice every five years.

Biofouling — the accumulation of barnacles, algae, mussels, and marine organisms on the hull surface — creates drag that reduces speed and increases fuel consumption. A clean hull can improve fuel efficiency by as much as 10–20%, making hull maintenance a key factor in both operational costs and environmental impact. Modern cleaning methods have advanced significantly, with remotely operated vehicles (ROVs) and cavitation technology now leading the industry alongside traditional diver-based cleaning.

Cavitation cleaning, which uses imploding water bubbles to remove fouling without damaging antifouling coatings, is increasingly the preferred method for its safety, speed, and environmental advantages. However, hull cleaning itself carries environmental risks, including the release of invasive species and toxic heavy metals from antifouling paint. Port authorities worldwide — including Australia, New Zealand, Norway, and the UK — have implemented varying regulations to manage discharge and protect local marine ecosystems.