Offshore energy is often pictured as a single rig sitting out at sea. In reality it is a connected chain of activity that runs from a government office on land all the way to a tanker loading hundreds of miles offshore, with specialist vessels and crews involved at every stage. This guide breaks down how offshore and marine energy actually works, the assets and roles that keep it running, and the certifications every offshore worker needs before they mobilise. It is written for anyone new to the industry, and for the people recruiting into it.
How offshore energy works, from approval to first oil
What are the stages of offshore oil and gas production?
Offshore energy production moves through four broad stages: licensing and approval, survey, drilling, and production. Each stage depends on the one before it, and each relies on its own specialist vessels and people.
1. Licensing and approval (onshore)
It starts on land. Before anything goes in the water, governments grant the licences and approvals that allow work to begin. Nothing moves without them.
2. Survey
Specialist survey vessels use radar and sonar to map the seabed, collect data and confirm exactly where the oil and gas sits. This is the groundwork everything else depends on.
3. Drilling
Drillships and rigs reach down to the reservoir, with blowout preventers in place to stop hydrocarbons escaping into the ocean. This is the phase most people picture when they think of offshore work, but it is only one step in a much longer process.
4. Production
The FPSO extracts, processes and stores the product offshore, then offloads it to tankers for export.
The key point is that offshore vessels are not tied to a single phase. From the seismic survey ships mapping reservoirs during exploration, to the drillships and semi-submersibles sinking wells, to the FPSOs and platforms in production, to the support fleet keeping it all running, each stage needs its own assets and its own people. At WRS, we crew across all of it. Understanding how the whole process fits together is what allows us to place the right people at the right stage, every time.
Know the fleet: the vessels and assets that keep offshore running
What types of vessels are used in offshore energy?
Offshore energy runs on a wide range of specialist vessels and assets, each built for a specific job. If you are new to the industry, or recruiting into it, it helps to know what does what.
| Drillship | Drills offshore wells and runs pipe to access deepwater oil and gas. Used for exploration, development and production wells. |
| Jack-up rig | The legs jack down to the seabed, lifting the hull clear of the water and locking the rig into a fixed, stable position. Stationary and safer in shallow water. |
| FPSO | Floating Production, Storage and Offloading. Processes hydrocarbons from subsea wells, stores the oil and offloads it to tankers. Effectively a processing plant at sea. |
| PSV / supply | Platform Supply Vessels deliver pipe, fuel and kit out to the field. |
| Anchor handling | Moves and sets moorings, buoys, chains and anchors to position and hold assets in place. Also tows rigs between locations. |
| Accommodation | A floating hotel providing crew accommodation, connected to the installation by gangway. |
| Survey vessel | Sonar and seismic equipment map the seabed and gather data before drilling begins. |
| ROV / subsea | Remotely Operated Vehicles handle subsea connections and inspections, piloted remotely from on board. |
*this list isn’t exhaustive
Every one of these assets needs a crew with the right tickets and the right experience. Knowing the difference between them is the starting point for getting offshore recruitment right, and it is where our specialist knowledge comes in.
The FPSO: a production hub at sea
What is an FPSO and what does it do?
An FPSO (Floating Production, Storage and Offloading vessel) is one of the most impressive assets working offshore. Think of it as a city on the water: a refinery, storage tank and export terminal in one vessel, stationed directly above the reservoir. It performs four functions:
- It draws the product up out of the reservoir through the riser and turret.
- It refines the oil and gas on board, separating the product from water and gas.
- It holds the processed product in the hull until it is ready to move.
- When ready, tankers connect and the FPSO offloads the product for export.
What makes an FPSO remarkable is that it combines every part of the production chain into a single floating asset, stationed exactly where it is needed and running continuously. That takes a large, highly skilled crew across a range of technical disciplines, and keeping those roles filled with the right people is exactly the kind of work we specialise in.
Staying put at sea: how dynamic positioning works
What is dynamic positioning (DP) on an offshore vessel?
Dynamic positioning (DP) holds a vessel in an exact position over a live well without using anchors. GPS and satellites feed the vessel its precise location, and onboard computers then drive the thrusters to counter wind, waves and current, holding position automatically. Constant, automatic adjustments mean the vessel barely moves.
It matters because working over live wells, subsea kit and around other assets leaves no room for error. Drifting even slightly can be dangerous, which is why DP is essential for so much offshore work.
The three DP classes
| DP1 | Basic dynamic positioning. Position is held automatically, but there is no backup if a single system fails. |
| DP2 | Redundancy is built in. Multiple thrusters plus stabilising systems keep the vessel in position even if one system fails. |
| DP3 | The highest class. Full redundancy, even against fire or flooding in one compartment. Used for critical operations. |
DP roles, including SDPOs, are among the most specialised positions offshore. Matching qualified DP crew to the right class of operation is a core part of what we do at WRS.
Anatomy of an offshore vessel
How is an offshore vessel laid out?
Every offshore vessel is really two things at once: a working platform and a home. Crews live on board for weeks at a time, so the vessel is split into working and living spaces, a self-contained community at sea. Broadly, there are four areas:
- The open working space, with cranes, winches and cargo.
- Engine room. Power and propulsion, where the engineers keep everything running.
- Living quarters. Cabins and berths, where crew rest on rotation.
- Mess and recreation. The galley, mess and recreation space, where crew eat and unwind.
On a supply or support vessel, the bridge and accommodation sit forward, with navigation, control and living space stacked together. The main crane lifts cargo and subsea kit on and off, while the large open aft deck carries pipe, containers and equipment out to the field. Below deck, the engine room and DP thrusters keep the vessel powered and in position. Understanding how a vessel is put together helps explain the range of roles on board, from crane operators to engineers to catering crew. Every one of those roles matters, and everyone needs the right person in it.
Who runs the ship: offshore crew ranks explained
What are the crew ranks on an offshore vessel?
An offshore vessel only works because of the people on it, organised into a clear structure. Crews are split into three departments, each with its own chain of command.
Bridge department
Led by the Master, the most senior person on board, followed by the Chief Mate, SDPO and 2nd Mate. This department runs navigation and overall command of the vessel.
Engine department
Led by the Chief Engineer, followed by the 2nd Engineer, 3rd Engineer, and the ETO, Motorman and Oiler roles. This department keeps the vessel powered and running.
Deck department
Led by the Shift Supervisor, followed by the Deck Foreman, Crane Operators, and the Bosun and ABs. This department handles the working deck and cargo operations.
Knowing how these ranks fit together is essential in offshore recruitment. Each role carries its own certifications, experience requirements and progression path, and getting the structure right is what keeps a vessel safe and productive. It is knowledge our consultants use on every placement.
Before you go offshore: the certifications every worker needs
What certifications do you need to work offshore?
You cannot simply turn up and work offshore. Every worker has to hold mandatory safety and survival training before they mobilise, and knowing which tickets are required is the first step for anyone looking to build an offshore career. The core ones are:
| BOSIET (3 days) | Basic Offshore Safety Induction and Emergency Training, the core offshore survival course. |
| FOET (1 day) | Further Offshore Emergency Training, the refresher that keeps BOSIET current. |
| CA-EBS (add-on) | Compressed Air Emergency Breathing System, covering underwater escape from a ditched helicopter. |
Beyond these, several others are common depending on the role: MIST, an offshore medical, and role-specific tickets such as rigging, welding, ETO and HSE.
Certifications are not just paperwork. They are what allow a worker to be on board safely and legally, and they are the first thing we check when placing crew. Making sure every candidate holds the right, in-date tickets for the job is a fundamental part of responsible offshore recruitment, and it reflects the commitment to safe working practices and high standards of compliance that underpins everything we do offshore.
Work with WRS’s offshore team
Whether you are building a project crew or planning your next tour offshore, the detail matters: the right tickets, the right experience, the right people at the right stage. As a global workforce solutions and recruitment consultancy partner, Worldwide Recruitment Solutions crews across the full offshore and marine lifecycle, from survey and drilling through to production and support.
If you are a client with roles to fill, our offshore team is ready to talk through your workforce requirements. Reach out to WRS’s offshore team to get started.
If you are a candidate looking for your next role offshore, explore our latest marine and offshore jobs here.
