21 March 2025
by Adam JamesGeneral Exemption for maritime autonomous surface ships (MASS) of Less than 2.5 metres in length overall
The Maritime and Coastguard Agency (MCA) has announced a new General Exemption for Maritime Autonomous Surface Ships (MASS) under 2.5 metres in length overall. Effective from August 5, 2024, this exemption enables eligible vessels to operate without requiring certification from the MCA or its delegates.
However, vessel owners and operators must comply with all applicable conditions outlined in the exemption to maintain their status.
The exemption marks a significant regulatory shift designed to support the growing MiniMASS sector, which includes remotely operated unmanned vessels (ROUVs). Traditionally, certification options for MASS were limited to case-by-case assessment through MGN 664 or compliance with the Workboat Code Edition 3. The new exemption provides a more streamlined approach for small autonomous vessels.
“We recognise the importance of enabling innovation in the autonomous maritime sector,” said an MCA spokesperson. “This General Exemption ensures that smaller MASS units have a proportional and accessible regulatory pathway, promoting technological advancement while maintaining safety at sea.”
Conditions and Compliance
While the exemption removes the need for MCA certification, it does not absolve vessels from all maritime regulations. Key conditions include:
- No Requirement for EPIRBs: The MCA assumes that MASS under 2.5 metres will not carry Emergency Position Indicating Radio Beacons (EPIRBs). If operators choose to equip EPIRBs, they must comply with The Merchant Shipping (EPIRB Registration) Regulations 2000.
- Ballast Water Regulations: The exemption assumes that these small vessels will not carry ballast water. If they do, they must comply with The Merchant Shipping (Control and Management of Ships’ Ballast Water and Sediments) Regulations 2022.
- Enhancing Visibility: The MCA strongly recommends that operators enhance their vessels’ visibility for safety, including fitting radar reflectors or radar target enhancers that comply with international standards.
Future Reviews and Industry Impact
The exemption will be reviewed alongside the Post-Implementation Review of Workboat Code Edition 3. Additionally, the MCA reserves the right to revoke the exemption if necessary.
The announcement has been welcomed by industry experts and innovators in the autonomous vessel sector. Many believe this move will encourage further development and deployment of small autonomous vessels, particularly in scientific research, environmental monitoring, and commercial applications.
The full exemption can be found here: MGN 702 (M) Amendment 1 Maritime autonomous surface ships of less than 2.5 metres in LOA - GOV.UK
British Marine members can seek more advice and guidance by emailing technical@britishmarine.co.uk