MSC 111 After the Vote: What the MASS Code Actually Changes

When Issue 21 went to press, the central expectation around MSC 111 was that IMO would adopt the non-mandatory MASS Code. That expectation has now materialised.

During its 111th session in London, the Maritime Safety Committee adopted the International Code of Safety for Maritime Autonomous Surface Ships — giving the industry its first formal global safety framework for ships operating with reduced, remote, or autonomous human control. IMO has described this as the first-ever global framework for maritime autonomous surface ships, emphasising that the MASS Code is initially non-mandatory and focused on enabling innovation while keeping safety, accountability, and the human element central. The vote is done. The code exists. And the next question — the more useful one — is what it actually changes for working maritime professionals.

What this is not

Before looking at what MSC 111 delivered, it is worth being precise about what it did not do.

It did not replace SOLAS. The MASS Code sits alongside the existing convention structure; it does not dismantle it. It did not make the framework mandatory. The code enters a voluntary phase, deliberately designed to allow flags, class societies, technology developers, and early operators to test application before mandatory implementation is considered. And it did not classify ordinary automated ships as MASS vessels. Integrated alarm management, voyage decision-support systems, and advanced condition monitoring are already standard on most modern merchant ships — none of these place a vessel inside the MASS framework.

This distinction matters practically. The MASS Code becomes relevant only when safe operation of a safety-critical function depends on remote or autonomous control rather than onboard crew execution. That is a categorical threshold, not a sliding scale of technical sophistication.

For trials already underway, the only IMO interim guidance that remains directly in force is MSC.1/Circ.1604, as West P&I has underlined, and the MASS Code will sit alongside that guidance until its provisions are folded into a mandatory SOLAS framework in the next decade.

The three things MSC 111 did not do — the clearest frame before reading further.

What this actually is

The correct reading of MSC 111 is not that autonomous ships are arriving across commercial fleets in the near term. It is that the industry now has a common regulatory architecture — and that architecture changes the terms of the conversation, permanently.

Before MSC 111, autonomous and remotely operated shipping projects could be framed as private technology experiments, evaluated against vague analogies with ordinary automation, and approved or rejected without a shared reference point. That phase is over. From this point forward, any serious MASS project must be measured against an adopted IMO safety code with a defined scope: surveys and certification, approval processes, risk assessment, system design, software principles, safe operations, alert management, manning and watchkeeping, navigation, connectivity, remote operations, fire safety, security, cargo handling, anchoring, machinery, and electrical installations.

This is a goal-based instrument, which is exactly the right architecture for a technology field still in active development. Overly prescriptive drafting would have locked in assumptions that early operational experience will inevitably challenge. The goal-based approach allows the framework to evolve as the evidence base builds.

The value of that design is already visible at the national level. South Korea's MASS Act — enacted in January 2024 and in force from January 2025, making it one of the first domestic autonomous shipping laws in the world — was deliberately constructed with the same regulatory flexibility. Under the Act, vessels operating within MOF-designated autonomous ship operating areas can receive exemptions from specific regulatory requirements after safety evaluation, including the crewing provisions under Article 11 of the Ship Officers Act that would otherwise prohibit unmanned trials. These designated zones are, in effect, structured sandboxes for goal-based validation. Safety is demonstrated through performance evidence, not by simply satisfying prescriptive rules written for crewed ships. The IMO MASS Code's experience-building phase operates on the same principle at the international level — and Korea's head start means its operational data will likely inform how the mandatory code is eventually drafted.

South Korea's MASS Act — a working model for the goal-based validation approach now embedded in the IMO code.

For the engine room and technical departments

Engineers, ETOs, and shore-side technical staff should read the MASS Code's treatment of machinery, electrical installations, software, and connectivity as confirmation that autonomous shipping is not purely a navigation problem.

A remotely operated or highly autonomous ship depends on machinery control reliability, fault tolerance, cyber resilience, power system stability, and well-defined degraded-mode behaviour. In practical terms, engineering assurance under MASS moves closer to control-system assurance and software assurance. The question is no longer just whether equipment is maintained to class requirements — it is whether the automated systems governing that equipment can demonstrate safe behaviour across the full range of operating conditions, including abnormal and emergency states, without physical intervention from onboard crew.

For engineers currently working aboard conventional vessels, the near-term effect is interpretive rather than operational. The MASS Code will not appear on your SMS or PMS in the immediate term. What it will do is shape the vocabulary and the documentation expectations for the condition monitoring, remote access, and automation integration that is already present on modern ships — particularly as those systems become subjects of PSC scrutiny and class survey in the coming years.

For navigation officers and bridge teams

For deck officers, the MASS Code introduces a new watchkeeping and manning framework for vessels where the traditional bridge watch may be remote or reduced. The practical questions the code forces into the open are not theoretical: who holds situational awareness, who receives and acts on alerts, how is handover managed, what happens during connectivity degradation, and how is collision avoidance responsibility maintained?

Central to these questions is the Remote Operations Centre — the ROC. Under MASS Degree 2 and above, the ROC is the entity from which a ship is controlled and monitored when no crew is exercising real-time navigation authority onboard. The MASS Code's human element framework is currently working through some of the hardest unresolved questions in the entire code — and most of them live at the ROC boundary. Who holds the conn during a handover from onboard automation to an ROC operator, and at exactly what moment does legal responsibility transfer? What communication latency between ship and ROC is acceptable before a safety-critical decision is considered compromised? If the ROC operator initiates a manoeuvre that results in a collision, does liability sit with the operator, the owner, the software developer, or the flag state?

The ROC boundary is where the MASS Code's hardest human-element questions are concentrated.

None of these questions have clean answers yet, and MSC 111 has not tried to pre-empt them. They are precisely what the experience-building phase is designed to surface — and they are the reason that navigation officers who understand the COLREGS framework deeply are better positioned than they might realise to contribute to how those answers are eventually written.

The LR post-session report confirms four additional provisions that navigation officers and technical staff should know. First, when crew or persons are on board a MASS, the master must be physically present onboard (Code II/14.2.1.12) — remote mastering is not permitted as a default. Second, the ROC is subject to the ISPS Code (II/5.8), meaning security obligations extend to shore control infrastructure. Third, emergency towing arrangements under SOLAS II-1/3-4 apply to MASS regardless of size — and remote or autonomous activation capability must be provided where no alternative rapid deployment means exist. Fourth, the MASS and ROC certificate templates finalised at MSC 111 are examples only, not standardised statutory forms: each flag state must develop its own certificate and record formats.

The code creates the formal structure in which these questions must now be addressed and audited. For most serving officers, the immediate implication is awareness: understanding the categorical distinction between the automation already aboard your vessel and the regulatory threshold at which that automation would require MASS-compliant governance.

For shore management, superintendents, and fleet functions

MSC 111 changes the management conversation from watch this space to prepare the governance model.

The voluntary code gives flags, class societies, technology developers, and early operators a recognised basis for design approval, survey logic, trials, and operational assurance — immediately. That means documentation quality, risk justification, management of change, and decision traceability become central considerations long before a mandatory code arrives.

For DPA-level and fleet management functions, the shift is strategic. Any project involving remote access, shore-based monitoring with decision authority, or reduced manning will need to be evaluated against whether it crosses the MASS threshold — and if it does, whether the governance framework in place is adequate. Liability and insurance positioning will follow the same logic.

Lloyd's Register has now published its post-session MSC 111 summary, confirming the key outcomes and providing the first class society framing of the adopted code. The LR report identifies CCC, HTW, III, NCSR, SDC and SSE as the sub-committees tasked with supporting development of the mandatory code. Detailed technical circulars and approval pathway guidance from individual class societies will follow as the experience building phase takes shape.

The timeline

The MASS Code has been adopted as a non-mandatory framework, with entry into effect on 1 July 2026. MSC 111 also developed a draft framework for the experience building phase (EBP) to be progressed at MSC 112, including the list of documents to be considered during that phase. The mandatory code is targeted for entry into force on 1 January 2032 — though the LR post-session report notes that MSC 111 itself acknowledged this date may be unrealistic and 2036 could be more appropriate. The 2032 date was retained but may be revised at a later stage.

The regulatory roadmap from adoption to mandatory implementation. Source: IMO MSC 111, May 2026.

Six years is not a long runway when you consider the depth of regulatory, technical, and operational change involved. Watchkeeping equivalence, cyber resilience, connectivity failure protocols, software assurance standards, emergency intervention frameworks, and the defined human role during abnormal conditions are all unresolved in detail. The experience-building phase exists to generate the evidence base needed to answer those questions responsibly.

The real outcome of MSC 111

The industry now has a common safety vocabulary for autonomous shipping. The regulatory discussion has moved from expectation to architecture, from possibility to adopted code.

Most ships in service today will continue to trade under conventional manning, conventional survey regimes, and conventional safety expectations. MSC 111 does not change that. What it changes is the framework within which any departure from those conventions — even incremental, technology-driven departures — will now be evaluated.

For maritime professionals, the most useful posture over the next 18 to 24 months is disciplined observation. Track how flag states apply the voluntary code. Watch how class societies structure approval pathways. Monitor where the hard unresolved questions surface. And recognise that the interpretive and documentary changes now underway are exactly how major future regulation begins — not with a fleet-wide operational disruption, but with a shift in what counts as a defensible answer to the question: is this safe?

The MASS Code has given the industry a structured basis for asking that question. That alone is a significant shift.

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Updated May 2026 with Lloyd's Register post-session MSC 111 summary report. Further updates will follow as DNV, ABS, KR, and ClassNK publish their post-session notes.