Vessel Types Explained: Bulk Carrier, Container, Tanker, Ro-Ro, and More

Bulk carriers transport unpackaged dry cargo in bulk — grain, coal, ore, cement, and similar commodities — loaded directly into large cargo holds rather than containers or packaging. This is the most numerous vessel type by count in the world fleet, and working aboard typically involves cargo operations tied closely to hold cleanliness and cargo-specific handling requirements, plus draft survey verification of loaded and discharged quantities.

Container ships carry standardized shipping containers (measured in TEU — twenty-foot equivalent units), typically operating on fixed liner schedules between specific ports rather than the more variable, opportunity-driven routing of a tramp trade vessel. Container ship work often involves working within relatively predictable schedules and more standardized cargo handling than bulk or break bulk operations, though larger vessels bring their own scale-related operational complexity.

Tankers carry liquid cargo in bulk — crude oil, refined petroleum products, chemicals, or liquefied gas, depending on the specific tanker sub-type. Tanker work involves genuinely distinct safety considerations (cargo flammability, vapor management, specific firefighting and containment protocols) and typically requires specific tanker endorsements beyond the base rank certificate — see our broader [STCW certificates explained](/blog/stcw-certificates-explained) guide for how these endorsements fit into the wider certificate landscape.

Chemical tankers and LNG (liquefied natural gas) or LPG (liquefied petroleum gas) carriers represent further specialization within the tanker category, often commanding premium compensation reflecting the additional technical training and risk profile involved.

Ro-Ro vessels are designed for wheeled cargo — vehicles, trailers, and rolling stock — that's driven directly on and off the vessel rather than lifted by crane, using ramps and a deck structure suited to vehicle stowage rather than container or bulk cargo handling. Ro-Ro operations involve a genuinely different cargo handling rhythm centered on vehicle loading/unloading logistics and lashing rather than crane-based cargo work.

General cargo vessels carry non-containerized, non-bulk cargo — machinery, steel products, project cargo, and irregularly shaped items that don't fit neatly into container or bulk categories. This work often involves more hands-on cargo securing and handling variety than more standardized vessel types, typically requiring closer crew involvement in lashing and securing than a standardized container or bulk operation.

Beyond conventional cargo-carrying vessels, offshore support vessels (supply vessels, anchor handling tugs, platform supply vessels) support oil and gas operations, while other specialized vessels (research, cable-laying, heavy-lift) each carry their own distinct operational profile. These often represent genuinely different career paths from conventional merchant shipping, sometimes with their own specific certificate or experience requirements beyond standard STCW ranks.