Understanding the Difference Between Supernumeraries and Occasional Workers on Yachts
Introduction
In the world of yachting, crew composition isn’t always straightforward. Beyond the captain, engineers, and stewards, yachts often carry additional personnel — individuals like nannies, security staff, chefs, personal trainers, or massage therapists who are temporarily employed onboard to serve the owner or guests.
However, these individuals aren’t always classified the same way under maritime regulations. Two key terms often cause confusion: Supernumerary and Occasional Worker. Understanding the distinction is critical for compliance with the Maritime Labour Convention (MLC) and for ensuring proper treatment, documentation, and insurance coverage for everyone onboard.
What is an Occasional Worker?
The term occasional worker is used in yacht codes (for example, the Red Ensign Group Yacht Code Annex E) to describe staff who normally work ashore but may be brought onboard a vessel for short periods, with no emergency duties, in service of the owner or charterer.
Key Criteria (from Annex E2)
No emergency duties onboard.
Must have familiarisation training onboard so they are capable of being self-sufficient in an emergency.
Must have a berth and access to mess and sanitary facilities meeting crew accommodation standards (or as required under MLC).
Must be at least 16 years old.
Must be medically fit to carry out their duties and be self-sufficient in an emergency (no full seafarer’s medical certificate required).
Must have a contract of employment that provides equivalent protection to that available under the MLC.
Must not bear the cost of food, medical care, or travel back to their home/workplace.
Must be trained in health & safety onboard.
If any of these criteria can’t be met, the individual must be treated as a passenger instead of an occasional worker.
Additional requirements:
The vessel’s DMLC Part II must include how occasional worker roles are handled.
Frequent or persistent use of the same individuals may reclassify them as seafarers.
The master should list them appropriately on the “list of crew.”
Essentially, the occasional worker category allows flexibility for short-term staff without invoking full seafarer status, provided strict criteria are met.
What is a Supernumerary?
“Supernumerary” is an older term still found in some national regulations (for example, RMI MI-108) describing:
“A person onboard a vessel employed by the owner and engaged in the business of the ship who, unless trained in basic sea survival and included in the crew Articles of Agreement, shall be treated as a passenger.”
In plain terms, a supernumerary is someone onboard in a capacity ancillary to the ship’s business but not part of the vessel’s crew complement — typically treated more like a passenger. While still used in some jurisdictions, modern yacht codes now focus on seafarers, occasional workers, and passengers, making “supernumerary” less precise.
| Feature | Occasional Worker | Supernumerary |
|---|---|---|
| Regulatory recognition (yacht codes / MLC) | Clearly noted in yacht-codes (e.g., REG / RY codes) as a category with defined criteria. | The concept exists in some national regs, but under MLC terms the category is largely archaic / subsumed. |
| Emergency duties / watchkeeping | Must not have emergency duties under the occasional worker definition. | By definition supernumeraries are not part of crew complement, therefore no full crew/watch duties. |
| Contractual / employment status | Must have an employment contract giving equivalent protection to MLC-style arrangement (though not full seafarer’s employment agreement). | Historically, may not be under full seafarer agreement; may be treated more like passengers or guest staff. |
| Accommodation / facilities onboard | Must have berth and mess/sanitary facilities at crew standard (or equivalent) for their accommodation. | May require accommodation but in practice could be more variable depending on flag/registry. |
| Age / medical fitness / training requirements | Minimum age 16; medically fit; must receive familiarisation training for emergencies. | Similar expectations might apply, but less clearly defined depending on flag state. |
| Treatment under MLC / seafarers’ rights | Occasional workers are not automatically seafarers, provided criteria are met. If arrangement becomes persistent/frequent, they may become seafarers. | Supernumeraries traditionally not part of crew, may be treated as passengers; less subject to seafarer rights but this creates risk and ambiguity. |
| Practical usage on yachts | Use when owner/charter brings onboard a specialist (e.g., nanny, masseuse, temporary bodyguard) for a short period not engaged in vessel operations. | Use when additional specialist personnel onboard but not part of regular crew operations; albeit the term is older and less precise under current MLC-regime. |
Why This Distinction Matters
There are several reasons why correctly classifying these roles onboard a yacht is important:
Regulatory Compliance
Misclassifying someone as a “passenger” when they are working onboard (or vice versa) can lead to flag state or port state control issues. For example, if an individual is working onboard and participates (or is required to participate) in emergency duties but is not treated as a seafarer, the vessel could be out of compliance. The occasional worker criteria set out in yacht codes help ensure compliance.
Seafarer Rights and Protection
Under the MLC, seafarers are afforded specific rights (employment agreement, hours of rest, repatriation, etc.). If a worker is actually acting like a seafarer (frequent onboard, emergency duties, etc.) but is treated as an occasional worker or passenger, you risk exposing the owner/operator/manager to claims.
Operational Safety
Any person on board must be familiar with the vessel’s emergency procedures, safety culture, and must be accommodated to a safe standard. Mis-treating working personnel as “guests” might bypass necessary safety/training steps.
Liability & Insurance
Crew lists, employment status, contracts, and accommodation standards all feed into risk assessments, insurance coverage, and port state control inspections. Ensuring the correct classification helps protect the owner/operator from regulatory or insurance surprises.
Cost and Administrative Implications
If someone is treated as an occasional worker (rather than full crew/seafarer), then administrative burden may be reduced (e.g., a full seafarer employment agreement may not be required) — but only if the criteria are clearly met. If the role evolves into something more permanent, you need to adjust and possibly treat them as a seafarer.
Practical Tips for Yacht Owners / Managers
Here are some practical suggestions to ensure you’re on the right side of the regulation and safe practice:
Define the role clearly upfront
When hiring someone to come onboard for a short stint (nanny, masseuse, bodyguard, etc.), clarify: Will they have no emergency duties? Will they be onboard only for a short period? Will they have a defined contract referencing the vessel and specifying their pattern of work?
Use written contracts / addenda
Even if the individual normally works ashore, ensure there is a contract (or an addendum to their shore-based contract) that references their work onboard the specific yacht. This helps meet the “equivalent protection” requirement under the occasional worker definition.
Ensure familiarisation training
Make sure that those onboard as occasional workers receive a brief training/familiarisation session covering essential emergency protocols, egress routes, and muster stations. Even if they don’t have watch duties, they must be capable of being self-sufficient in an emergency.
Accommodation & facilities standard
Provide a berth and access to mess and sanitary facilities of an appropriate standard — especially if the vessel is treated under the MLC or yacht-code regime that references MLC-style standards.
Age & medical fitness
Check that individuals are at least 16 years old and medically fit for their duties onboard (though not necessarily holding full seafarer medical certificates).
Track frequency of use
If someone comes onboard very frequently, the “occasional” nature may be lost; the risk is that they would be treated as a seafarer. Maintain records of how often and how long the individual is onboard.
List the person onboard appropriately
Even though they are “occasional workers,” they should still be included on the vessel’s crew list (or an “Occasional Workers Record”) and clearly named (e.g., Bodyguard (occasional)). This helps with inspections and crew list verification.
Flag state / yacht code alignment
Ensure you check what the vessel’s flag state requires and what yacht code you are operating under (e.g., the Red Ensign Group Yacht Code, the Marshall Islands Yacht Code) and align your practices accordingly. For example, the Marshall Islands code defines “carriage of supernumeraries” in its Yacht Code.
Be cautious with the term “supernumerary”
While you may encounter the term in older guidance or regulations, treat it as a risk indicator if used — ask: Is this person really part of the crew complement? Are they performing operational duties? If yes, then perhaps they should be treated as seafarers.
When the “Occasional Worker” Becomes a Seafarer
One of the “red flags” is when the arrangement stops being occasional or temporary and becomes routine. If the same individual is onboard frequently or permanently, and/or has emergency duties or participates in vessel operation/watchkeeping, then they likely should be treated as a seafarer under the MLC.
Once the status becomes that of a seafarer, the vessel operator must ensure compliance with full seafarer employment agreements, hours of work/rest requirements, repatriation rights, accommodation standards for crew, etc.
Failure to recognise this transition can lead to non-compliance and potential issues during port-state inspections, flag audits, or in liability/insurance situations.
Summary
Occasional Worker: A clearly defined category in yacht codes for short-term staff onboard who carry out non-crew duties, do not have emergency/watch duties, are onboard only for limited periods, and meet certain criteria (accommodation, contract, training, etc.).
Supernumerary: Historically the term used for ancillary persons onboard not part of the crew complement. Under modern yacht/MLC regimes, the term is less frequently used and the category is less precise; essentially many of those roles now fall under occasional workers or seafarers depending on their duties.
The correct classification matters for regulatory compliance (MLC, yacht code, flag state), safety, rights and protection of personnel, and operational/insurance risk.
Yacht owners and Captains should adopt robust procedures (contracts, training/familiarisation, accommodation, record-keeping) to ensure those working onboard in short-term roles are treated appropriately — and to monitor when a role may be evolving into a seafarer role.
How Dayboard Yacht Solutions Can Help
At Dayboard Yacht Solutions, we recognize that modern yachting often blends professional operations with personal service — and that regulatory clarity is essential for smooth operations.
Our team works directly with yacht owners, captains, and charter companies to:
Review and classify all personnel onboard in accordance with MLC and Flag State requirements.
Draft compliant contracts for occasional workers and supernumeraries.
Update DMLC Part II documentation to accurately reflect vessel practices.
Coordinate with Flag Administrations (including the RMI, Cayman Islands, and others) to ensure the yacht’s compliance framework remains watertight.
Provide crew and owner briefings on the responsibilities and entitlements of each category.
Whether you’re onboarding a personal chef for a short trip or a full-time nanny for seasonal cruising, Dayboard ensures your vessel remains compliant — and your team protected.