If the people, systems and decisions that keep a ship operationally safe are no longer all on board, how does the industry prove that safety is still under control?
As maritime operations move toward autonomous and remotely operated ships, this question becomes central. Before asking when these vessels will become common, the industry needs to understand what happens to safety when control, monitoring, watchkeeping, judgement and emergency response are no longer confined to the ship itself, but shared between the ship, shore, intelligent systems and human operators.
From Onboard Presence to Distributed Responsibility
For generations, maritime safety has been built around human presence at sea. Masters, officers, engineers and watchkeepers were not just positions in a crewing table. They were the people who lived with the conditions and risks, felt the ship, experienced the environment, responded to alarms, made judgement calls and carried responsibility in real time within the same physical space.
The emergence of Maritime Autonomous Surface Ships (MASS) challenges this model. Functions that were once carried out, supervised or controlled on board may now involve Remote Operations Centres (ROCs), software systems, and human operators working from different locations.
This shift makes the safety question more complex. It is no longer only whether the technology works. The harder question is whether safety can still be demonstrated, trusted and approved when the operation itself is no longer centred only on the ship.
Why the MASS Code Matters to Everyone
The MASS Code should not be read only as a regulatory or technical document. Its importance lies in how it connects different parts of maritime operations around the same safety discussion.
Ports, pilots, SAR authorities, policy makers, insurers, lawyers, seafarers, unions, training providers, surveyors, terminal operators and shipping companies will each meet MASS from a different point in the operation. For some, the issue may arise at port entry or in congested waters. For others, it may arise through emergency response, certification, training, liability, surveying or budget planning.
At this stage, the Code does not provide every final answer. It offers a shared framework for addressing these questions in a structured way, rather than relying on existing rules designed for fully crewed ships to cover every new operational arrangement.
What Actually Counts as MASS?
A key clarification in the Code is that enhanced automation alone does not make a ship a MASS.
Modern ships may already have advanced digital systems, automated tools or decision-support technology. But under the MASS Code, the important question is whether autonomous or remotely operated technology augments or replaces functions that would normally be performed by onboard crew involved in conducting or controlling ship functions.
This distinction shifts the focus away from the technology itself and toward the way the ship is operated.
The practical questions become:
where does control sit, what role remains on board, what is handled remotely, what is performed by software, and whether existing IMO instruments are sufficient for that way of operating.
Where and How the Code Applies
The MASS Code applies to cargo ships covered by SOLAS chapter I, including any associated Remote Operations Centre, where the ship has systems or functions that enable autonomous or remote operations and where the Administration considers existing instruments impracticable or insufficient.
It does not apply to cargo high-speed craft, warships, naval auxiliaries or government ships used only on non-commercial services.
Importantly, the Code does not replace SOLAS or the wider IMO framework. It supplements them. Stakeholders should therefore read the MASS Code alongside SOLAS, ISM, ISPS, COLREG, STCW and other relevant instruments, not in isolation
A Flexible, Goal-Based Approach
The MASS Code is goal-based, technology-neutral and non-mandatory at this stage, but it has been developed in a way that can support a future transition to mandatory status.
It does not prescribe one fixed technical solution for autonomous or remotely operated functions. Instead, it asks whether the proposed operation can be shown to achieve the required safety, security and environmental protection outcomes under defined conditions.
This is important because technology-neutral does not mean technology without control, and it does not mean promoting one technical solution over another. It means the Code leaves room for different approaches, but any chosen solution still has to be assessed, explained, tested and supported by evidence.
The result is a practical balance. The Code allows innovation, but not without evidence. It aims to enable MASS and conventional ships to operate safely alongside each other, while keeping human oversight, human-system collaboration and clear responsibility within the framework.
Understanding the Code Structure
Part I – Foundations
Part I sets out the purpose, principles, application, structure and definitions of the Code. These definitions matter because they give industry and Administrations a shared language for discussing responsibility, control, safety, security, approval and evidence in MASS operations.
One useful example is the term “agent”. The Code defines an agent as a human or software responsible for performing or supervising control actions. This is important because it shows that control in MASS operations may involve both people and software, not only crew physically on board, and recognises a more distributed operational environment.
Part II – Implementation Backbone
Part II sets out the principles that should be met as part of the MASS approval and certification process. It covers areas such as surveys and certificates, the approval process, risk assessment, operational context, system design, software principles, management of safe operations, maritime security, alert management, manning, training, watchkeeping and maintenance.
The important point is that a MASS operation is not assessed only by looking at the technology. The ship, any associated Remote Operations Centre (ROCs), the Concept of Operations, operational limits, task allocation, people, systems, procedures and records all become part of the approval and certification assessment.
Part III – Operational Functions
Part III deals with specific MASS operations and functions, including navigation, connectivity, remote operations, structure, subdivision, stability and watertight integrity, fire protection, fire detection and fire extinction, search and rescue, carriage of cargoes, anchoring, towing, mooring, and machinery and electrical installations.
This part is also goal-based. It is not a one-size-fits-all checklist. What applies will depend on the mode of operation, the functionality being certified and how the MASS is intended to operate. Chapters should generally be applied in full, unless waived with the agreement of the Administration as part of the approval process.
What This Means for Industry Stakeholders
One of the main takeaways is that the question is no longer simply whether a ship is MASS or not.
The more useful questions are practical: what is the operating mode, how many people are on board, where the master is located, which functions are automated or remotely controlled, and how tasks are divided among onboard crew, shore-based operators, and software systems?
The answers matter because they affect safety, operational arrangements, legal responsibility and the overall structure of the operation. A ship with persons on board and some autonomous or remotely operated functions will not raise the same issues as a ship operated remotely with reduced or no persons on board. A MASS operating in open waters will also raise different questions from one entering pilotage waters, approaching a port or operating in congested waters. Monitoring a function remotely is not the same as controlling it remotely.
Where a Remote Operations Centre is involved, the operation is no longer centred only on the ship. The shore-based part of the operation also needs to be understood, assessed and managed as part of the wider safety arrangement.
Looking Ahead: From Framework to Implementation
The non-mandatory MASS Code provides an important starting point, but the work is not finished.
Discussion will continue through IMO’s Experience-Building Phase and through relevant IMO bodies considering training, technical, operational, legal and other related matters.
Even so, industry does not need to wait for every answer to be finalised. Stakeholders can already read the Code against their own responsibilities, identify where future pressure points may arise, and consider what should be raised while the framework is still being developed.
Final Thought
The MASS Code should not be seen only as a technical or operational document. It should also be read as an implementation roadmap for how maritime responsibility, competence and operations may change as autonomous and remote operations develop.
This non-mandatory period gives the industry time to question, prepare and contribute while the framework is still being shaped.
We will be providing further in-depth analysis of the anticipated experience building phase in future articles.
Note
This article is based on the May 2026 version of the non-mandatory MASS Code available at the time of writing. It provides a brief commentary on selected parts of the Code and should not be read as a complete or official interpretation. For full details, readers should refer to the full text of the non-mandatory MASS Code and relevant IMO documents.
