During a fog passage in the North Sea, two vessels passed at 0.3nm with no prior visual or sound signal contact — detected only by ARPA. Both vessels took avoiding action. No damage occurred. Must you report this?

A. POST-FOG NEAR-MISS REPORTING OBLIGATIONS: YES — this is a reportable near-miss event. OBLIGATIONS: (1) COMPANY SMS NEAR-MISS REPORT: under ISM Code Section 9.1, the operator must have procedures to report and investigate non-conformities, accidents, and hazardous situations (near-misses). A 0.3nm CPA in restricted visibility with no sound signal contact is a classic near-miss. Report to DPA immediately; (2) MAIB REPORTING: MAIB Reporting Regulations 2012 require reporting of any "marine incident" which is an event (other than a casualty) where a ship, person, or load is endangered. A 0.3nm CPA in fog, North Sea — this meets the threshold. MAIB can be notified by telephone (23-hour duty: 023 8023 2527) or online; (3) DECK LOG: comprehensive entry of times, positions, ARPA data, actions taken, CPA achieved, outcome. Name of other vessel if known (AIS); (4) VDR DATA PRESERVATION: if any investigation is likely, the VDR data should be preserved (download before it is overwritten — most VDRs have a 12-hour rolling loop but some are longer); (5) FLAG STATE: UK flagged — MCA may also wish to be notified; (6) MASTER'S DUTY: SOLAS V/31 requires masters to communicate navigational hazards to other ships and authorities. In this case, the visibility and traffic situation could constitute a hazard to be broadcast on VHF.

B. No reporting is required as no damage occurred and both vessels took avoiding action. Only incidents involving actual contact or damage are reportable under MAIB regulations.

C. The near-miss should be reported to the port agent at the next port of call, who will decide whether it meets the MAIB reporting threshold.

D. VDR data automatically transmits near-miss data to MAIB in real time. No manual reporting is required if the vessel is fitted with a type-approved VDR.

A. SAFE SPEED IN RESTRICTED VISIBILITY — Rule 6 assessment (COLREG Rule 6): safe speed requires consideration of: (a) state of visibility (300m — severely restricted); (b) traffic density (Dover Strait is one of the world's busiest waterways — separation scheme traffic plus local traffic); (c) manoeuvring ability — your vessel's stopping distance at 12 knots (a 140m bulk carrier may take 15+ ship lengths to stop); (d) background lighting at night; (e) draught — your squat in shallow Dover Strait approaches. AT 12 KNOTS WITH 300M VISIBILITY: stopping distance will greatly exceed 300m — you cannot stop within the distance you can see. Rule 8(e) requires reduction to minimum steerage way if necessary to avoid collision. IMMEDIATE ACTIONS: (1) Sound fog signal — one prolonged blast every 2 minutes (Rule 35a — power-driven vessel underway making way); (2) Reduce speed to safe speed — likely 5-6 knots or less to ensure vessel CAN STOP within visibility range; (3) Post extra lookout — Rule 5 — additional lookouts on bow in fog; (4) ARPA on — operating on appropriate scale, all targets tracked; (5) VHF Ch 16 / Ch 11 (Dover VTS DOVER COASTGUARD) monitored; (6) Navigation lights on; (7) Master already called — correct. Safe speed is your judgement call — document your reasoning in the log.

B. Safe speed in fog is defined as half the vessel's normal service speed. At 12 knots service speed, 6 knots is automatically the correct safe speed under COLREG Rule 6.

C. Rule 6 safe speed assessment applies only when vessels have radar — a vessel without radar is exempt from safe speed requirements in restricted visibility.

D. With visibility of 300m, the vessel should anchor immediately in the Dover Strait to await improvement, regardless of traffic density or depth.

A. RULE 19(d) — Action when radar contact detected (no visual contact): COLREG Rule 19(d): a vessel which detects by radar only another vessel shall determine if a close-quarters situation is developing and/or risk of collision exists. If so, take avoiding action in ample time. The action must be: (a) A LARGE ALTERATION OF COURSE — Rule 19(d)(i): if possible, avoid an alteration of course to port for a vessel forward of the beam other than for a vessel being overtaken; (b) AVOID ALTERING COURSE TOWARDS A VESSEL ABEAM OR ABAFT THE BEAM — Rule 19(d)(ii); (c) REDUCE SPEED — reducing speed, stopping engines, or reversing may be needed. IN YOUR SCENARIO: CPA 0.1nm is a close-quarters situation. TCPA 8 minutes gives time for action. RECOMMENDED ACTION: (1) Reduce speed immediately (further — to minimum steerage); (2) Alter course to starboard — large alteration (minimum 30-40°) to open the CPA; (3) Sound appropriate fog signals; (4) Monitor ARPA to confirm action is working — CPA must open; (5) DO NOT alter to port (risk of swinging your bow into the other vessel's path); (6) VHF — if other vessel is a known contact, alert them, but do not rely on VHF agreement. Rule 19 is clear — radar action must be early, substantial, and effective.

B. With CPA 0.1nm and TCPA 8 minutes, the situation is not yet a close-quarters situation under COLREG Rules. Maintain course and speed while monitoring the target.

C. Call the other vessel on VHF Ch 16 and agree a port-to-port passing. Once verbal agreement is reached, no course alteration is necessary.

D. Stop engines and anchor immediately — Rule 19 requires vessels to anchor when a close-quarters situation develops in restricted visibility.