ISO 6319 gives ports a method, not an answer

The first international standard for conducting and documenting in-water cleaning has been available since March. Its authors are clear that it does not say when a port should grant a permit. That omission, more than the standard’s content, is shaping the positions of owners, cleaning contractors and coatings suppliers ahead of PPR 14. The committee meets at IMO headquarters in London from 25 to 29 January 2027.

Speaking on Riviera Maritime Media’s webinar, ISO 6319:2026 in Practice: In-Water Cleaning, Inspection and the New Compliance Baseline, panellists examined a standard that is operationally useful but still lacks action thresholds, a verification regime and consequences for non-compliance.

ISO 6319:2026, Conducting and documenting in-water cleaning of biofouling on ships, was published by ISO/TC 8/SC 2 in March. It emerged from the Clean Hull Initiative, launched by Bellona and Jotun in 2021. It was drafted alongside ISO 20679:2025, a companion standard covering independent performance testing of in-water cleaning systems. Contributors included the Port of Antwerp-Bruges, Jotun and Wallenius Wilhelmsen.

What the standard will not do

Irene O. Tvedten, the Bellona Foundation’s senior adviser on maritime issues and leader of the drafting project, identified chronology as the standard’s principal strength. It takes a cleaning event from preparatory assessment through monitoring to post-cleaning documentation. IMO’s 2025 guidance on in-water cleaning, MEPC.1/Circ.918, does not provide the same end-to-end process.

The standard is deliberately narrower in scope. It does not address coating selection. It also separates cleaning provisions at biofouling rating 1, above which capture requirements become more stringent.

Its omissions are intentional. Ms Tvedten said the standard gives ports a decision-making process, but does not set risk-acceptance criteria or consequences for non-compliance. Those matters remain for IMO to decide. They include action thresholds, performance criteria, inspection frequencies and enforcement.

PPR 13 agreed in February 2026 to recommend a standalone convention rather than amendments to Marpol Annex VI. The aim is to finalise a draft legal framework by 2029 for consideration at MEPC 89. This is a drafting milestone, not an entry-into-force date. The distinction matters because 2029 is often presented as the compliance deadline.

Ms Tvedten’s concern is not that regulation will be too stringent. It is that it will remain incoherent. Ports currently tend either to ban in-water cleaning outright or to permit it with few distinctions. In her view, neither approach serves the environment.

Bellona argues that cleaning is the solution, rather than the problem. That is a campaigning position and should be understood as such. However, the Port of Antwerp-Bruges and IMO’s own guidance now recognise controlled cleaning as a legitimate practice.

The investment standoff

A sharp commercial intervention came from Nick Laker, SeaTec’s operations director for underwater services. SeaTec is part of V.Group’s marine services arm and operates across a global port network.

SeaTec has adopted the fouling-rating scoring system. It has not yet invested in closed-circuit hull cleaning. Its investment has so far extended only to closed-circuit propeller polishing.

Mr Laker’s reasoning was clear. Capture equipment costs millions, but there is no level playing field against which to recover that investment. He warned that vessels could route through deregulated zones to avoid capture requirements. That would undermine the business case for early investors.

His proposed sequence was equally clear: establish repeatable recording first, then create the confidence needed to invest in recovery systems.

That approach is rational for a contractor. It also means that the capture capacity implied by a binding convention remains limited. By the supplier side’s own account, the market is still immature. Mr Laker described closed-circuit hull-cleaning providers as early adopters operating in an infancy market.

He was unequivocal on safety. IMCA published D082, Guidance on Diving Operations in Support of Underwater Ship Husbandry, in January 2024. It followed at least five reported diver deaths connected to underwater ship husbandry during 2023. IMCA has said the activity has one of the highest fatality rates in commercial diving. Incidents are often linked to SCUBA rather than surface-supplied equipment.

Mr Laker argued that surface supply should be the minimum standard. He said price-led procurement is driving safety failures.

Prevention and its regulatory cloud

Two panellists argued that the cheapest clean is the one avoided.

Markus Jönsson, chief executive of I-Tech, argued that barnacle settlement is primarily a function of vessel activity, rather than coating failure. Risk rises when ships operate below roughly six knots and during idle periods.

I-Tech’s dry-dock study covered 685 vessels. It found barnacles on nearly 90 per cent of inspected tankers, compared with about 70 per cent of pure car carriers and container ships. More than one-third of the full sample arrived with more than 10 per cent hull coverage.

Dr Sasha Heriot, Cathelco’s product development business manager, presented prevention as compliance planning, rather than a fuel-efficiency measure. Lighter fouling requires less aggressive removal. It also reduces coating damage and provides a cleaner evidential baseline.

Cathelco is part of Evac Group. It supplies electrolytic marine-growth-prevention systems that dose sea chests and pipework with copper ions. It has also launched a new generation of ultrasonic hull systems.

The independence problem

Mark Riggio, owner of Simplify Ballast, chaired the ISO drafting groups and is technical director of BEMA. He returned repeatedly to two related issues: compatibility; and third-party verification.

Ms Tvedten confirmed that the working group found no formal IMO definition of compatibility. It therefore created one. The group settled on a requirement for assessment, rather than testing.

The distinction matters. Testing language is reserved for water-quality impacts, which ISO 20679 can support. Compatibility testing is close, Ms Tvedten said, but not yet established. The main beneficiary would be the owner, who currently avoids proactive cleaning because of concerns about coating damage.

Mr Riggio argued that extending dry-docking intervals on the strength of in-water reports would require independent assessment. That could an include independent review of ROV footage.

Asked whether SeaTec uses independent assessors, Mr Laker said the company writes its own reports. He also acknowledged that the process is subjective.

The evidential chain therefore runs from a contractor’s self-authored report, to an owner’s biofouling record book, and then to a port state. That may be sufficient for permitting. It remains well short of the evidence class would need before relaxing a bottom-survey requirement. Mr Riggio suggested that coating service life, rather than documentation, would be the limiting factor in any case.

PPR 14 will begin to address the central question. If IMO sets action thresholds before the capture fleet is in place, and before compatibility can be tested rather than simply asserted, who bears the cost of the gap? It may be the owner denied entry, the contractor that invested early, or the port that continues to say no.

Riviera has further webinars scheduled on 12 October, examining what happens when international biofouling guidance meets coastal state reality, and in November on biosecurity at the border. To register for the webinars, as well as view and register for the Friday 22 January London Workshop, please click here.