Medical fitness at sea

Your seafarer medical certificate

Every seafarer needs a valid medical certificate. The rules come from two international conventions, which most flag states follow:

• the Maritime Labour Convention 2006 (Regulation 1.2), which requires a certificate confirming you’re medically fit for your duties
• the STCW Convention (Regulation I/9), which sets the medical standards for certificated seafarers

The ILO and IMO publish joint guidelines on the medical examinations of seafarers. Approved doctors in many countries use them to decide whether a condition is compatible with work at sea.

Each flag state approves its own doctors and issues or recognises certificates. You’ll know your certificate by its national name, for example the ENG1 in the UK. Many flag states accept certificates issued by other countries.

Possible outcomes

• Fit: for all duties, in all waters.
• Fit with restrictions: for example limited to certain duties, near-coastal waters, or a shorter validity.
• Temporarily unfit: for example until a condition is stable or a dose of medication settles.
• Permanently unfit.

Does a neurodivergent diagnosis stop you passing?

Not automatically. The international guidelines focus on whether a condition affects your ability to work safely, not on the diagnosis itself. The key questions an approved doctor considers are:

1. Can you do your duties safely?

   Including routine work, watchkeeping and emergency duties, such as fire-fighting or abandon ship.

2. Is your condition stable?

   Doctors look for a settled pattern, including on any medication.

3. Could you become unwell at sea?

   Where medical help may be days away, doctors consider the risk of a sudden deterioration.

4. Are there other conditions?

   Such as anxiety or depression, which are common alongside neurodivergence and are assessed in their own right.

Many autistic seafarers, and seafarers with ADHD or specific learning differences, hold certificates with no restrictions.

Medication

If you take medication, including ADHD medicines, the doctor will want to know:

• what it is, the dose, and how long you’ve taken it
• whether the dose is stable
• whether it has side effects that could affect safety, such as drowsiness, or affect sleep with your watch pattern
• what would happen if you missed doses or ran out at sea

You’ll also need to plan:

• supply: enough medication for your whole contract, plus a margin for delays
• repeat prescriptions: how you’ll get them while away, especially if your prescriber is in another country
• travel rules: some ADHD medicines are controlled drugs, and some countries require permits, letters or specific quantities. See our ADHD medication map.

Preparing for your medical

A good specialist letter explains your diagnosis, how it affects you day to day and at work, how stable you are, any medication, and your specialist’s view on your ability to work safely. If the doctor examining you is in another country, a letter in English, or with a certified translation, avoids delays. Evidence of sea service, appraisals and references shows the doctor how you manage in practice.

Hiding a condition or medication could invalidate your certificate and put you and your crewmates at risk.

If you’re refused or restricted

The MLC says seafarers who are refused a certificate, or given restrictions, should be able to have the decision reviewed by another independent doctor or referee. How you ask, and the time limits, depend on the flag state, so ask the approved doctor or the flag state’s maritime authority straight away.

Include any extra evidence from your specialist, and explain clearly why you think the decision is wrong. Your union or a seafarers’ welfare organisation may also be able to help.