MCA Notices: MSN, MGN, MIN and the MSN 1858 Syllabus

Read first: how a convention becomes law. This topic explains how the UK publishes the detail of those rules as M-notices, and where your own oral syllabus now lives.

Three Kinds of M-Notice

In short: the MCA speaks to the industry through M-notices. There are three kinds, and they differ in legal weight and in how long they last.

Source: MCA collections of MSNs and MINs on the UK government website.

• Memory hook: MSN = Must · MGN = Guidance · MIN = Information (short life).
• The SI is the law. The MSN carries the SI’s technical detail, so following the MSN is compulsory too. An MSN is not “an SI issued by the MCA”.
• An MGN is not law in itself, but do not treat it as optional. Some MGN content repeats a requirement that is mandatory elsewhere, and the MCA tags some MGNs as “Statutory guidance”.
• A MIN expires. Expect a cancellation date; expired MINs are removed from the MCA’s active list.
• On the bridge: a surveyor asks why you did something. If an MSN covers it, you had no choice. If an MGN covers it, show that you followed it, or explain what you did instead.

Reading an M-Notice Number

In short: type + number + suffix + amendment tell you what the notice is, who it is for, and which version you hold.

• Type: MSN, MGN or MIN.
• Number: a running number for each type (current MSNs are in the 1800s and 1900s; MGNs run up to the 700s).
• Suffix (MCA):
  • (M) = merchant ships;
  • (F) = fishing vessels;
  • (M+F) = both.
• Amendment: “Amd 2” replaces Amd 1. Example: MSN 1858 (M+F) Amd 2 replaced Amd 1 on 18 May 2026. Always use the latest one.
• Decode one: MGN 324 (M+F) Amd 2 = Marine Guidance Note no. 324, for merchant and fishing vessels, second amendment.
• Common slip: the small-vessel code is MGN 280, not “MSN 280”.

From Convention to M-Notice

In short: an international rule reaches your bridge in steps. Each step adds detail.

1. The IMO adopts a convention (SOLAS, STCW, MARPOL, COLREG).
2. The UK makes it national law: regulations made as Statutory Instruments (“Merchant Shipping (…) Regulations”).
3. An MSN sets out the technical detail of the SI — mandatory.
4. An MGN explains how to comply and what good practice looks like.
5. A MIN gives short-lived information (dates, timetables, contacts).

• Example: STCW sets training and certification. MSN 1858 (M+F) applies it to yacht deck officers, using the STCW Chapter II training elements and the equivalents allowed by STCW Article IX (MSN 1858 Amd 2).

Finding and Using M-Notices

In short: the MCA pages of the UK government website are the official home of every M-notice. Check the version before you rely on one.

• The MCA keeps three collections there: Merchant shipping notices (MSNs), Active marine guidance notes (MGNs) and Marine information notes (MINs).
• The M-notices relevant to your ship belong with the compulsory publications on the bridge.
• The OOW oral syllabus puts them next to the Annual Summary of Admiralty Notices to Mariners: know the contents and use of both (item 3.3.1).
• A replaced notice stays online marked “Withdrawn”, with a line saying what replaced it. An old printed copy on board may be out of date.
• Check the suffix (M, F) and the size and type of vessel the notice applies to.
• Notices a yacht OOW should know by name: MSN 1858 (M+F) (yacht deck certificates), MSN 1868 (M) Amd 1 (safe manning and watchkeeping), MGN 324 (M+F) (VHF and AIS), MSN 1895 (M) (REG Yacht Code Part A).

MSN 1858: Deck Officers on Large Yachts

In short: MSN 1858 (M+F) sets the UK route to yacht deck certificates. The current version is Amendment 2, in force from 18 May 2026.

• Full title: UK Requirements for Deck Officers on Large Yachts (24m and over).
• For: commercially and privately operated yachts and sail training vessels of 24 m and over.
• Covers: the certification structure, training and assessment for yacht-restricted OOW, Chief Mate and Master.
• Amd 2 replaces Amd 1 (18 May 2026).
• Candidates call MSN 1858 “the syllabus” because it defines what you must hold and pass. The oral examination syllabuses themselves are no longer inside the notice: the MCA publishes them separately online.

The Oral Examination Syllabuses

In short: the MCA collection Deck Officer Yacht Oral Examination Syllabuses (first published 26 January 2023, updated 17 June 2026) holds one syllabus per certificate. Read the one for your exam.

• The six syllabuses:
  • Master (code vessels less than 200 GT) / OOW (yachts less than 500 GT);
  • OOW (yachts less than 3000 GT);
  • Master (yachts less than 500 GT);
  • Master (yachts less than 3000 GT);
  • Chief Mate (yachts unlimited);
  • Master (yachts unlimited).
• The OOW (yachts less than 3000 GT) syllabus has three functions:
  1. Navigation — plan and conduct a passage, keep a safe navigational watch, manoeuvre the ship.
  2. Response to emergencies — navigational emergencies, other emergencies, communications.
  3. Onboard ship operations — pollution prevention, seaworthiness, legislative requirements, business and law.
• 3.3 Legislative requirements:
  1. Contents and use of MSNs, MGNs, MINs and the Annual Summary of Admiralty Notices to Mariners.
  2. Current Merchant Shipping health and safety law and the Code of Safe Working Practices.
  3. IMO conventions on safety of life at sea and protection of the marine environment.
  4. Purpose and application of the ISM Code.
  5. Purpose of flag and port State control.
  6. Purpose and application of the ISPS Code.
• 3.4.1: content and application of the yacht codes — the Small Vessels Code and the Large Commercial Yacht Code (LY3).
• 3.4.5: safe manning, hours of work and watchkeeping.

The Yacht Codes: What the Syllabus Names and What Is Current

In short: the syllabus (17 June 2026) still names MGN 280 and LY3 / MSN 1851, “or any subsequent amendment”. The MCA’s own notice pages show both have been replaced. The two sources differ, so know both.

• In the exam: name what the syllabus names, then say what replaced it. “LY3 was the Large Commercial Yacht Code; it is now replaced by the REG Yacht Code Part A under MSN 1895.”