Workboat Code 3, Annex 2: What UK Rules Actually Say About Remote and Unmanned Workboats

The UK-Specific Detail Behind the Headlines

IMO's MASS Code sets the global framework for autonomous shipping. Annex 2 of Workboat Code Edition 3 is the UK's own detailed rulebook for a specific, real category already operating today: Remotely Operated Unmanned Vessels (ROUVs) under 24m Load Line Length, working as workboats. If you're on the deck or engineering side of an operation moving toward remote or autonomous small-vessel work, this Annex — not the MASS Code headlines — is where the actual operational requirements live.

What a ROUV Is Not Allowed to Do

The Code is explicit and restrictive. A Remotely Operated Unmanned Vessel shall not: be fitted with a deck crane or other lifting device (except for survey equipment, case-by-case); carry a spare portable petrol container; have an engine that can only be hand-started; carry any open-flame appliance or gas installation; carry a liquid-fuelled galley cooker or heater; be a dedicated pilot boat or hold a pilot boat endorsement; be fitted with a diver lift or used as a diving platform; transfer passengers or industrial personnel; carry dangerous goods (beyond a narrow exception for paint/paint-related material and aerosol lubricants for the vessel's own use); tow another vessel or object (again, survey equipment excepted); or operate as a mother vessel.

In exchange for these restrictions, an equally long list of main-Code sections simply don't apply — Life-Saving Appliances (Section 14), Accommodation and Recreational Facilities (Section 21), Medical Care (Section 23), and Dangerous Goods carriage (Section 29) among them. The logic runs both ways: strip out anything that assumes people are physically aboard, and add back a set of remote-operation-specific controls instead.

The Working Log — What Actually Has to Be Recorded

Every ROUV must keep a working log at the control position covering: pre-departure checks, course and compass error, weather, speed, overboard discharges, cargo weight, the duration and location of any signal loss, loss-of-steering events, engineering/navigational/safety alarms, impaired situational awareness (a failed camera or sensor counts), bilge pump activation, completed maintenance, critical-system test results, every accident, and — specifically — every near miss, including supporting evidence for any COLREGS departure made to avoid immediate danger. Handover between watchkeepers, changes of designated Master, and every switch of control between Remote Operation Centres must also be logged.

Voyage Data — the 30-Day Rule

Beyond the working log, a wide set of technical parameters — position, speed, heading, which Remote Operation Centre is in control, onboard and control-centre audio, camera/sensor output, radar, ECDIS and echo sounder data, alarms, rudder and propulsion order-and-response, hatch/door status, payload deployment, acceleration, hull stresses, wind, roll, AIS, and every command sent to the vessel — must be recorded both on board and at the Remote Operation Centre. All of it has to be retained for a minimum of 30 days. If the data format is proprietary to the manufacturer, the owner/operator must make a conversion tool and licence-free replay software available to the investigating authority on request — not just the raw data itself.

Fire and Bilge — Adapted, Not Removed

A ROUV isn't exempt from fire and flooding safety, but the requirements are re-engineered for an unmanned vessel: bilge pumps must be power-driven and automatic-starting (no one is aboard to start them manually), fitted with either oily water separators or oil sensors that automatically stop pumping and alarm at the control position if oil is detected. On a fire being detected, machinery-space fans, fuel/oil transfer pumps, and centrifuges must automatically stop — actions a crew would normally take by hand.

Check Your Vessel

• Owner/Operator: If you're operating or considering a ROUV, does your data retention and handover-logging setup actually meet the 30-day rule and the full working-log field list — not just position and speed?
• Remote Operation Centre staff: Do you know exactly what counts as a reportable ‘near miss’ under this Annex, and is your evidence-capture process ready to support a COLREGS-departure justification if one's ever needed?
• Engineering: Is your critical-equipment list current, and does it reflect the redundancy requirements this Annex specifically calls for?

Source: The Safety of Small Workboats and Pilot Boats — A Code of Practice, 3rd Edition (MCA, published 22 January 2025, in force 13 December 2023), Annex 2. See also MGN 664(M+F) Amendment 1 on certification for vessels using innovative technology.