Jotun HSS’ “always clean hull” verified by DNV

The independent verification confirms no measurable speed loss and an always clean hull under real operating conditions. Based on a combined assessment of physical in-water inspections and verified performance monitoring in line with ISO 19030, the verification confirms that hulls protected with HSS remain effectively free from fouling throughout the observation period.

The verification represents a significant milestone for hull performance management, providing independent, third-party confirmation that continuous hull cleanliness can be achieved and sustained in operation — and that this cleanliness translates directly into maintained vessel speed.

“Our HSS, including our robotic hull cleaner The HullSkater, was designed to deliver an always clean hull and today we are thrilled to announce that the findings mark the first time this has been independently verified under real-world operating conditions,” said Helle Vines Ertsås, Global Category Manager for HSS in Jotun.

The verification is grounded in physical inspection data from in-water inspections carried out across a sample of 33 vessels. These inspections consistently confirmed the absence of fouling, providing direct evidence that the hulls remained in a clean condition throughout the assessed period.

In parallel with the physical inspections, DNV assessed performance monitoring data from 12 vessels operating under HSS. The analysis showed no measurable speed loss, using an average of 3.5 years of in-service data, including a one-year reference period as per ISO 19030. This confirms that the verified clean hull condition is not only visible through inspections but also reflected in vessel performance data.

“DNV’s role has been to independently assess the inspection and performance data from vessels operating with Hull Skating Solutions. The analysis confirmed that the hulls remained clean throughout the review period and that no measurable loss of speed occurred. This provides Jotun with third-party verification that the solution performed as intended under real operating conditions,” explained Olav Rognebakke, Head of Section Hydrodynamics and Stability at DNV.

HSS is Jotun’s proactive hull cleaning solution designed to prevent fouling from developing in the first place.

“Using the robotic HullSkater to inspect and proactively clean the underwater hull, early-stage fouling is removed before it can attach and grow, and that keeps the hull in a clean condition while the vessel remains in operation. The HullSkater works in harmony with a dedicated high performance coating, SeaQuantum Skate, approved and recognised as compatible with the HullSkater. The solution is also backed up by proactive condition monitoring and technical service,” Vines Ertsås said.

Hull fouling has historically been managed through periodic drydocking and reactive cleaning.

“This verification demonstrates that proactive, continuous hull maintenance through HSS can prevent fouling from developing in the first place,” said Morten Sten Johansen, Global Category Director for Hull Performance in Jotun

With this verification, HSS establishes a new reference point for what constitutes a clean hull in practice. Rather than relying on assumptions or indirect indicators, hull condition and performance are verified through documented inspections and ISO-aligned performance data.

“Credible speed loss data matters. Without it, operators face operational and regulatory risk, and fleet decarbonisation plans can be built on the wrong assumptions. Independent verification, like through DNV, is how we turn claims into documented performance. Ensuring real environmental effect for the industry, the ocean and the planet is important elements in our Clean shipping commitment,” said Johansen.