Five-year revalidation of certificates and the two seagoing service routes (STCW Regulation I/11)
2026-08-07

Say a chief officer finishes a posting ashore and goes back to sea. The expiry date printed on the certificate of competency has not passed yet. Is that certificate enough to join on. STCW Regulation I/11 answers with an interval rather than a date.
The interval is five years. Inside that window there is not one thing to prove again but two, and one of the two, continued professional competence, can be proved by seagoing service, which itself splits into two routes. This follows that split through Regulation I/11 and section A-I/11 of the STCW Code.
Five years is not the date on the certificate but the interval between proofs
1 Every master, officer and radio operator holding a certificate issued or recognized under any chapter of the Convention other than chapter VI, who is serving at sea or intends to return to sea after a period ashore, shall, in order to continue to qualify for seagoing service, be required, at intervals not exceeding five years, to:
One sentence fixes both the persons and the scope.
- It names the master, officer and radio operator. Ratings are not the persons this provision calls.
- The certificates are those
issued or recognized. Certificates issued by the flag State and foreign certificates it has recognized are both caught. - Certificates arising under chapter VI of the Convention are out. Their renewal sits in another provision.
- It reaches not only those serving at sea but those who intend to return after a period ashore.
at intervals not exceeding five years is a ceiling, not a cycle. It means the gap between two
proofs must not run past five years. So for someone whose time ashore has stretched out, this
interval bites before the expiry date does.
Medical fitness and continued professional competence do not stand in for each other
.1 meet the standards of medical fitness prescribed by regulation I/9; and .2 establish continued professional competence in accordance with section A-I/11 of the STCW Code.
The word joining the two lines is and. Filling one does not fill the other.
Medical fitness is set by regulation I/9 and continued professional competence by section A-I/11 of the STCW Code. The provisions differ and so do the papers that prove them. A fresh medical certificate is no proof of time at sea, and ample seagoing service says nothing about medical fitness. Each requirement runs on its own calendar.
Seagoing service is given not as one number but as two windows
1 Continued professional competence as required under regulation I/11 shall be established by: .1 approved seagoing service, performing functions appropriate to the certificate held, for a period of at least: .1.1 twelve months in total during the preceding five years, or .1.2 three months in total during the preceding six months immediately prior to revalidating; or
Between .1.1 and .1.2 sits or. Both do not have to be met. The two alternatives differ in
the length of the window counted and in the total demanded.
| Alternative | Window counted | Total to be filled |
|---|---|---|
.1.1 |
the five years before revalidating | twelve months |
.1.2 |
the six months immediately before it | three months |
The long window asks for twelve months in total, the short one for three. So someone who spent a long stretch ashore still clears this requirement by serving three months inside the six months before revalidating. Conversely, several voyages across five years do not clear it by this route if the total falls short of twelve months.
Two qualifiers the provision attaches to the service have to be read with it: approved and
performing functions appropriate to the certificate held. The first means the service must be
in a form the flag State accepts. The second means that having been on board is not enough on
its own. The test is the function performed, not the length of the stay.
When neither window is filled, an approved test or course takes that place
.2 having performed functions considered to be equivalent to the seagoing service required in paragraph 1.1; or .3 passing an approved test; or .4 successfully completing an approved training course or courses; or .5 having completed approved seagoing service, performing functions appropriate to the certificate held, for a period of not less than three months in a supernumerary capacity, or in a lower officer rank than that for which the certificate held is valid immediately prior to taking up the rank for which it is valid.
All four are strung together with or. Seagoing service is only one of five ways to establish
continued professional competence.
.2 covers functions accepted as equivalent to that seagoing service. .3 is passing an
approved test and .4 is completing an approved training course. .5 is seagoing service
again, on different terms: three months or more served in a supernumerary capacity, or in an
officer rank below the one the certificate is valid for, and immediately before taking up that
rank.
The word approved appears in three places. The test, the course and the service under .5
must all have been approved. A record of in-house training the company built for itself does not
fill this slot. An approved refresher and updating course has to carry changes in national and
international regulations on safety of life at sea, security and protection of the marine
environment, and to take account of any updating of the standard of competence.
One sentence is addressed to the Parties rather than to seafarers. A Party compares the standards of competence required for certificates issued before 1 January 2017 with part A of the STCW Code, and determines whether their holders need refresher training or assessment.
Tankers add a second proof inside the same five years
Paragraph 3 of Regulation I/11 says that to continue serving on tankers a master or officer must meet the requirements of paragraph 1 and, on top of that, establish continued professional competence for tankers at intervals not exceeding five years. The tanker proof does not replace the general one. It sits on top of it.
3 Continued professional competence for tankers as required under regulation I/11, paragraph 3 shall be established by: .1 approved seagoing service, performing duties appropriate to the tanker certificate or endorsement held, for a period of at least 3 months in total during the preceding 5 years; or .2 successfully completing an approved relevant training course or courses.
The five routes of the previous section come down to two here. By service it is three months in total in the preceding five years, and the duties have to match the tanker certificate or endorsement held. Where those three months are missing, the one remaining road is an approved relevant course.
The window is the same five years, but the total is three months rather than twelve. The two counts run separately in one person’s file.
Worth confirming
The passages above come from Regulation I/11 in STCW/CONF.2/33 (printed pages 13 to 14) and
section A-I/11 in STCW/CONF.2/34 (printed pages 25 to 26). That is as far as the text goes.
What counts as approved, which papers prove seagoing service, and who runs refresher courses on
what cycle are left to the flag State. Where a revalidation application is filed, and whether the
six-month route is accepted in practice, also vary by flag State. The administrative guidance
issued by that ship’s flag State is where the real judgement starts.
Revalidation is not settled by the date printed on the certificate. Bellbook keeps the certificates and the medical certificate expiry date on the personnel record card, and sign-on and sign-off records show which ship the seafarer was on and for how long.
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