The International Maritime Organization (IMO) has adopted a new International Code of Safety for Maritime Autonomous Surface Ships (MASS Code). It was adopted at the 111th session of the Maritime Safety Committee (MSC) in London. The Code starts on a voluntary basis.
A Maritime Autonomous Surface Ship (MASS) is a ship capable of operating with varying levels of independence from human interaction. This ranges from automation with crew on board, to remotely-controlled vessels with or without crew, to fully autonomous vessels able to make decisions independently. While the number of fully crewless or remote-operated ships are currently limited, a growing number are being successfully trialled internationally.
The IMO MASS Code aims to support the safe integration of autonomous and remotely operated commercial ships into global shipping. It sets out a comprehensive, goal-based framework to ensure that autonomous vessels are built, operated and certified at equivalent safety and environmental standards to conventional ships. They will also be required to comply with the International Convention for the Safety of Life at Sea (SOLAS) and other applicable mandatory IMO instruments.
Also read: IMO MEPC works towards consensus on Net Zero Framework
Master retains responsibility
The MASS Code introduces new requirements for the design, approval and operation of these ships, including in key areas such as navigation, connectivity, remote operations, fire safety, and search and rescue. It places strong emphasis on risk assessment, robust system design, cybersecurity and the integration of Remote Operations Centres (ROCs).
Importantly, it underscores the importance of human oversight, with the master retaining overall responsibility for the ship at all times – even if not on board the ship.
From voluntary to mandatory
The Code applies to large internationally-trading cargo ships and will take effect from 1 July 2026. It will start on a voluntary basis for at least two years, giving member states the opportunity to test its use while paving the way for making it mandatory under the SOLAS Convention.
The roadmap continues as follows:
- December 2026 – develop a framework for an Experience-building phase (EBP) post adoption of the non-mandatory MASS Code.
- 2028 – commence development of the mandatory MASS Code, based on the non-mandatory Code and result from the EBP and review conducted by the relevant sub-committees, and consider amendments to SOLAS (new chapter) for the Code’s adoption;
- By 1 July 2030 at the latest – adoption of the mandatory Code, for entry into force on 1 January 2032.
IMO Secretary-General Mr. Arsenio Dominguez: ‘This landmark achievement positions IMO at the forefront of regulating emerging technologies, demonstrating the Organization’s ability to anticipate and shape the future of shipping. It represents a major step forward, enabling innovation while ensuring that safety, accountability and the human element remain at the core of maritime operations.’
Picture by IMO.
Also read: IMO calls for safe-passage framework in Strait of Hormuz
