Ultrasonic Thickness Measurement and Hull Gauging in Rijeka

Inspection services for ships at Rijeka

Each service has its own page with the method, the class requirements and what the report contains.

Where gauging happens in Rijeka and around Kvarner

Most structured gauging around Rijeka happens at Viktor Lenac. A ship in one of the yard's floating docks is accessible from keel to deck, tanks are cleaned and gas-freed by the yard, and the technicians follow the yard's programme so readings are ready before steel gangs are allocated. For conversion projects the team gauges the structure that will be cut, extended or reinforced, and later re-gauges renewed areas. Ships also lie at the yard's repair quays before and after docking, which gives time for tank work afloat.

Away from the yard, gauging is done at the terminals. Tankers at the JANAF terminal and LNG carriers at the Omišalj LNG terminal can have their main deck, deck lines and any ballast tanks opened for entry gauged during discharge under strict terminal safety rules. Bulk carriers at Bakar give access to holds and hatch covers once discharged, and container ships at Brajdica and the Zagreb pier offer limited-scope access during cargo work, usually for ballast tanks and hatch covers. The ship's agent arranges ISPS access at each terminal and books launches for ships at anchor in Kvarner.

• Viktor Lenac shipyard, Martinšćica — floating dock gauging of bottom shell, sea chests, tanks and structure to be converted, plus re-gauging of renewed steel
• Omišalj, island of Krk — deck, deck piping and ballast tank gauging on crude tankers at the JANAF terminal and LNG carriers at the LNG terminal
• Bakar dry bulk terminal — once a bulk carrier's cargo is out, its holds, hopper tanks and hatch covers are open for gauging
• Adriatic Gate container terminal, Brajdica — hatch cover and ballast tank readings on feeder and mainline container ships, taken around crane work
• Rijeka Gateway terminal, Zagreb pier — container ship gauging within the cargo window, planned with the terminal and the ship's agent
• Kvarner Bay anchorages — ships waiting for a yard slot or a berth, where pre-docking and sale gauging can be done from a launch

Port state control, emissions and the Croatian maritime market

Croatian port state control officers inspect foreign ships in Rijeka under the Paris MoU, applying the same EU rules used in Italy and Slovenia. Kvarner and the rest of the Adriatic fall within the Mediterranean SOx ECA, effective 1 May 2025, which limits fuel sulphur to 0.10% unless a scrubber achieves the same emissions. For scrubber-fitted ships, a docking at Rijeka is the natural moment to gauge wash-water and overboard piping and the shell around the outlet, while the ship is dry and the system is shut down, rather than chasing those readings in service.

Calls at Rijeka and Omišalj count towards both EU ETS, extended to shipping in 2024, and FuelEU Maritime, in effect from 2025; for owners deciding whether an older ship justifies a major steel renewal at the yard, the emissions rules and the gauging results are weighed together. Croatia also has a long shipowning and seafaring tradition, with shipping companies along the coast and many Croatian officers and engineers in international fleets, while Split is home to the Croatian Register of Shipping, Croatia's IACS-member classification society. Croatia is in the Schengen area and uses the euro, which keeps travel for yard projects straightforward.

Since 1 May 2025 the whole Mediterranean has been a sulphur emission control area, so ships calling at Rijeka burn 0.10% sulphur fuel or run a scrubber. Scrubber wash-water piping, the overboard discharge and the hull penetration around it corrode quickly in service and are worth adding to the gauging scope at every docking.

How a thickness measurement job runs at Rijeka

A gauging job at Rijeka runs the same way whatever the ship type. The sequence below is what the superintendent, the attending surveyor and the yard can expect from us.

Rijeka Airport is on the island of Krk, close to Omišalj, and Zagreb Franjo Tuđman Airport offers wider connections with a motorway link to the coast; Trieste and Ljubljana airports are also within road distance. The yard and the terminals require ISPS or site passes, arranged through the agent or Viktor Lenac, and launch transfers to the Kvarner anchorages are booked by the agent. Croatia's Schengen membership means our Indian technicians enter on a Schengen visa. Yard dockings are booked well ahead, which suits visa planning; terminal calls need dates confirmed as soon as they are known.

• Send the vessel name or IMO number, ship type, class society, the survey due (annual, intermediate, renewal survey number, CAP or owner's condition survey), the port and dates, and the scope you expect.
• We confirm the scope against the class rules for that survey, prepare the thickness measurement plan with frame and section references, and say whether the measurement will be credited to a class survey.
• Mobilisation is planned around visa lead times and the vessel's schedule; the ship's agent arranges port access, and the yard or ship arranges staging, lighting, ventilation and gas-free certificates.
• Gauging with calibrated ultrasonic thickness gauges: through sound coatings only where the gauge's through-coating mode has been verified on a coated reference, otherwise on cleaned bare steel, with every reading tied to its frame, strake and location on the sketch.
• Readings are compared with original thicknesses as work proceeds; substantial and excessive corrosion and any cracks are reported to the attending surveyor and the superintendent the same day.
• The final report is issued on the class thickness-measurement formats with sketches, a summary of locations exceeding the allowable margins, piping tables where piping was in scope, and the gauge calibration and technician certificates.

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