Shipboard organization is the rank structure that assigns every crew member’s duties on a merchant ship. A typical cargo ship has three departments: deck, engine and catering, and each is led by a senior officer who reports to the master.
The shipboard organizational chart below shows who reports to whom. The table after it lists each rank with its STCW certificate and main duties, for cadets, new seafarers and anyone curious about life on board.
What Is Shipboard Organization?
Shipboard organization is the system that defines each person’s rank, department, duties and reporting line on board. The master has overall command, and three heads of department run deck, engine and catering work beneath him.
Every rank is either an officer or a rating. Officers hold an STCW certificate of competency and stand watches in charge; ratings carry out the work under their supervision.
Structures vary with ship type and crew size, but the pattern is internationally recognized. This article follows the structure used on a typical general cargo ship; tankers add a pumpman, and passenger ships add a large hotel department.
Merchant Ship Ranks at a Glance
| Rank | Department | Reports to | STCW certificate | Main duties |
|---|---|---|---|---|
| Master (Captain) | Command | Company | II/2 Master | Overall command, safety, legal and commercial duties |
| Chief Officer (Chief Mate) | Deck | Master | II/2 Chief Mate | Cargo, stability, deck crew, 04–08 watch |
| Second Officer (Second Mate) | Deck | Chief Officer | II/1 OOW | Passage planning, charts, 00–04 watch |
| Third Officer (Third Mate) | Deck | Chief Officer | II/1 OOW | Lifesaving and firefighting gear, 08–12 watch |
| Deck Cadet | Deck | Chief Officer | In training (record book) | Supervised watchkeeping and deck work |
| Bosun | Deck | Chief Officer | II/5 Able Seafarer Deck | Leads deck ratings, maintenance, mooring |
| Able Seaman (AB) | Deck | Bosun / OOW | II/5 Able Seafarer Deck | Lookout, helm, mooring, maintenance |
| Ordinary Seaman (OS) | Deck | Bosun | II/4 RFPNW | Lookout, cleaning, assisting ABs |
| Chief Engineer | Engine | Master | III/2 Chief Engineer | All machinery, fuel and engine crew |
| Second Engineer | Engine | Chief Engineer | III/2 Second Engineer | Day-to-day engine room management, main engine |
| Third Engineer | Engine | Second Engineer | III/1 OOW Engine | Boilers, generators, fuel and bunkering |
| Fourth Engineer | Engine | Second Engineer | III/1 OOW Engine | Purifiers, pumps, sewage and bilge systems |
| Electro-Technical Officer (ETO) | Engine | Chief Engineer | III/6 ETO | Electrical, electronic and control systems |
| Engine Cadet | Engine | Second Engineer | In training (record book) | Supervised engine room work |
| Fitter, Oiler / Motorman | Engine | Second Engineer | III/5 or III/4 | Repairs, welding, watch support |
| Wiper | Engine | Second Engineer | Basic safety (VI/1) | Cleaning and general engine room work |
| Chief Cook | Catering | Master or Chief Officer | Ship’s cook (MLC Reg. 3.2) | Galley, menus, food safety |
| Steward / Messman | Catering | Chief Cook | Basic safety (VI/1) | Serving meals, cleaning accommodation |
Why Is Shipboard Organization Important?
Clear organization makes a ship safe: every person knows their duties, their watch and their station in an emergency. In a fire, collision or man-overboard situation, a well-organized crew responds in seconds rather than minutes.
Each crew member is assigned to a department, a watch and a muster station. The structure also decides who maintains which equipment, so nothing falls between departments.
The flag State sets the minimum crew for each ship in its Minimum Safe Manning Document. IMO Resolution A.1047(27), Principles of Minimum Safe Manning, adopted in 2011, guides how that number is set.
The STCW Convention sets the training and certificate each rank needs. The STCW certificate a seafarer holds decides which positions they can legally fill.
What Is the Chain of Command on a Merchant Ship?
The master commands the ship. The chief officer heads the deck department and is second in command. The chief engineer heads the engine department and reports directly to the master.
- Master: overall command and final authority on safety and pollution prevention
- Chief Officer: deck department, cargo and stability; takes command if the master is incapacitated
- Chief Engineer: engine department; reports to the master, but command passes to the chief officer, not the chief engineer
- Chief Cook or Chief Steward: catering department
Under the ISM Code, the company must state the master’s overriding authority in its safety management system. That authority lets the master make any decision for safety or pollution prevention, and ask the company for help.
The Deck Department: Ranks And Responsibilities
The deck department navigates the ship, handles cargo and maintains the hull and deck equipment. It is headed by the chief officer and includes the second and third officers, deck cadets, the bosun and the deck ratings.
Captain or Ship Master
The master is the ship’s highest authority and acts on behalf of the owner or operator. He rises through the deck department and holds an STCW II/2 master’s certificate.
The master is responsible for safe navigation, the crew’s safety and welfare, and compliance with law in every port. In narrow channels and port approaches he works with the pilot, but the pilot’s presence does not relieve him of command.
Ashore-facing work also lands with the master. This includes port clearance, crew wages and accounts, provisions and the ship’s official log.
First Mate or Chief Mate
The chief mate, or chief officer, heads the deck department and is second in command. He is responsible for cargo operations, stability, deck maintenance and the deck crew.
He stands the 04–08 navigation watch and keeps the hull, cargo gear, accommodation, and lifesaving and firefighting equipment in order. The chief mate also runs crew and cadet training, including ship drills for fire, abandon ship and rescue.
On many ships the chief officer is also the Ship Security Officer under the ISPS Code.
Second Mate
The second mate is the ship’s navigation officer and third in command after the master and chief officer. He keeps charts and publications corrected and maintains the bridge navigation equipment.
He prepares the passage plan for each voyage under the master’s direction. The second mate stands the 00–04 and 12–16 watches, and on many ships also acts as medical officer.
Third Mate
The third mate, or third officer, is the most junior deck officer and usually the ship’s safety officer. He maintains lifeboats, liferafts, firefighting equipment and emergency systems, and stands a bridge or cargo watch.
By tradition the third mate keeps the 08–12 and 20–24 watches. Those are the hours when the master and senior officers are usually awake and close to the bridge if help is needed.
Deck Cadet (or Apprentice)
The deck cadet is a trainee officer, usually a maritime college student, who holds a seaman’s book but is not yet an officer. Under STCW Regulation II/1, the cadet completes at least 12 months of approved seagoing service, recorded in a training record book.
Six months of that service must be bridge watchkeeping under a qualified officer. In the United States, most cadets train through one of the maritime colleges and academies in the US.
Boatswain or Bosun
The bosun is in charge of all deck duties, including ship upkeep and deck equipment repair. As the most senior deck rating, he leads the team of ABs and ordinary seamen and reports to the chief officer.
Deck ratings stand lookout and helm watches, work as day workers on maintenance, or combine both. Ratings in a navigational watch need an STCW II/4 certificate of proficiency, the RFPNW.
The 2010 Manila Amendments added a higher rating certificate, Able Seafarer Deck under Regulation II/5. Bosuns and ABs normally hold it.
Who Stands Which Bridge Watch?
On a ship with three deck officers, each stands two four-hour watches a day. The pattern below is the traditional one; companies can change it.
| Officer | Night watch | Day watch |
|---|---|---|
| Second Officer | 00:00–04:00 | 12:00–16:00 |
| Chief Officer | 04:00–08:00 | 16:00–20:00 |
| Third Officer | 20:00–24:00 | 08:00–12:00 |
The Engine Department: Ranks And Responsibilities
The engine department runs and maintains all machinery on board, from the main engine to the sewage plant. Engineers report to the chief engineer, and engine ratings support them on watch and in maintenance.
Engine room work is hands-on and can get hot, reaching 45–50°C (113–122°F). Heat at that level carries real physiological risk. Our guide to extreme heat hazards faced by seafarers covers what to watch for and how to manage it.
Many modern ships run unmanned machinery spaces (UMS) at night. Engineers then work days and take turns as duty engineer on call.
Chief Engineer
The chief engineer heads the engine department of a merchant vessel and holds an STCW III/2 certificate, known as a “Chief’s Ticket”. “The Chief” is responsible for the operation and maintenance of all engineering equipment on board.
He reports directly to the master and manages fuel and lubricant stocks, machinery budgets and the engine crew.
Second Engineer
The second engineer runs the engine department’s daily maintenance and operations and reports directly to the chief engineer. Because he plans and supervises most of the work, he is usually the busiest engineer on board.
The main engine and its systems fall under his direct responsibility. On ships with a manned engine room, he traditionally stands a watch as well.
Third Engineer
In the engine department, the Third Engineer is normally in charge of boilers, fuel, auxiliary engines, condensate, and feed systems, reporting to the Second Engineer. Knowing the boiler mountings and accessories fitted to those boilers is a core part of standing that watch.
“The Third” is the third most senior engineer and usually handles bunkering on the engine side. Our guide to third engineer duties and responsibilities covers the role in detail.
Fourth Engineer
The fourth engineer is the most junior engineer officer and reports to the second engineer. He typically looks after fuel and lube oil purifiers, sewage treatment, bilge and oily water separator systems.
It’s a wide brief for the most junior officer in the department. Our rundown of the Fourth Engineer’s responsibilities covers what the role looks like day to day.
The fourth engineer usually stands a watch and often maintains the lifeboat engines with the third mate.
Electro-Technical Officer (ETO)
The ETO maintains the ship’s electrical, electronic and automation systems, from generators and switchboards to bridge equipment. The rank became a separate STCW certificate, Regulation III/6, with the 2010 Manila Amendments.
Engineering Cadet (or Apprentice)
An engineering cadet is a trainee engineer who holds a seaman’s book but is not yet an officer. Under STCW Regulation III/1, the cadet combines workshop skills training with at least 12 months of approved seagoing service.
Six months of that time must be engine room watchkeeping under a qualified engineer.
Ratings Forming Part of an Engineering Watch (RFPEW)
Engine ratings who stand watch on a seagoing ship with main propulsion of 750 kW or more must be certified under STCW Regulation III/4. Senior engine ratings, such as fitters and motormen, hold the Able Seafarer Engine certificate under Regulation III/5.
Wipers do cleaning and general engine room work and are the usual entry rank in the department.
The Steward Department
The steward, or catering, department feeds the crew and keeps the galley and accommodation clean. On a cargo ship it is usually a chief cook and one or two stewards or messmen.
Chief Steward
The chief steward heads the department on larger ships. He is responsible for the galley, pantry and provisions, oversees the cook and stewards, and keeps all catering areas sanitary.
On most modern cargo ships the chief cook does this job and no separate chief steward is carried.
Chief Cook
The chief cook runs the galley, plans menus with the master and orders supplies. He is responsible for food hygiene and for meals that respect the crew’s cultural and religious needs.
Under Regulation 3.2 of the MLC 2006, a ship’s cook must be trained, qualified and found competent. No one under 18 may work as a ship’s cook.
Steward
A steward or messman serves meals, cleans the mess rooms and accommodation, and helps in the galley. Larger ships may carry separate stewards for officers, crew and passengers.
Smaller crews on modern cargo ships mean fewer stewards, and on many ships the role is combined with general duties.
How Do US Merchant Marine Ranks Differ?
US ships use the same structure with different engine titles. The engineer ranks are numbered as assistants to the chief, so the US First Assistant Engineer is the international Second Engineer.
| International title | US title |
|---|---|
| Chief Officer | Chief Mate |
| Second Officer | Second Mate |
| Third Officer | Third Mate |
| Second Engineer | First Assistant Engineer |
| Third Engineer | Second Assistant Engineer |
| Fourth Engineer | Third Assistant Engineer |
| Motorman / Oiler | Oiler or QMED |
US licensed officers usually start as third mate or third assistant engineer after an academy program or years of sea service. Every candidate must also meet the age and medical requirements for seafarers.
No. Merchant navy ranks are civilian job titles on commercial ships, tied to the STCW certificate each person holds. Navy ranks are military grades with a separate command structure and their own rank insignia.
Some merchant officers also hold a naval reserve commission, but that rank does not apply on a commercial ship.
How Can You Tell a Ship Officer’s Rank?
Most shipping companies show officer rank with gold stripes on shoulder boards or sleeves. Four stripes mark the master and chief engineer, and one stripe the most junior officers.
- 4 stripes: Master, Chief Engineer
- 3 stripes: Chief Officer, Second Engineer
- 2 stripes: Second Officer, Third Engineer
- 1 stripe: Third Officer, Fourth Engineer
Deck officers often wear a diamond or anchor above the stripes, and engineers a propeller. Uniform rules are set by each company, so details vary.
Related Topics
- Essential seamanship skills every seafarer needs
- What a ship cargo plan is and who prepares it
- Famous captains in maritime history
Frequently Asked Questions
Who is in charge of a merchant ship?
The master, or captain, has overall command and final authority on safety and pollution prevention. The chief officer heads the deck department and the chief engineer heads the engine department, and both report to the master.
What is the highest rank on a ship?
The master is the highest rank on board. The chief engineer also wears four stripes as head of the engine department. If the master cannot act, command passes to the chief officer.
Who is second in command on a ship?
The chief officer, also called the chief mate or first mate, is second in command. He heads the deck department and takes over command if the master is incapacitated.
What does a third officer do on a ship?
The third officer is the most junior deck officer and usually the safety officer. He maintains lifesaving and firefighting equipment and traditionally stands the 08–12 and 20–24 bridge watches.
What are the three departments on a ship?
A merchant ship has a deck department, an engine department and a catering, or steward, department. Passenger ships add a large hotel department for guest services.
What is the difference between officers and ratings?
Officers hold an STCW certificate of competency and can be in charge of a watch or department. Ratings, such as ABs, oilers and stewards, work under officers and hold certificates of proficiency.
How do you become a ship’s officer?
Most officers start as cadets, combining college study with at least 12 months of approved sea service. They then pass the national exam for an STCW officer certificate, such as officer of the watch or third mate.
What is a shipboard organizational chart?
It is a diagram of every rank on board, grouped by department and connected by reporting lines. It shows who each crew member reports to, from ratings up to the master.
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