Hull Gauging in Algeciras: Ultrasonic Thickness Measurement at Berth and Anchor

Inspection services for ships at Algeciras

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

Where gauging happens around Algeciras Bay

Gauging in Algeciras is planned around one of three settings: a terminal berth, a liquid-bulk berth or the anchorage. On a container ship, the terminal's crane programme and lashing gangs set the pace, so the team works in spaces that do not interfere with cargo — engine-room and double-bottom tanks, void spaces, the steering gear flat and the scrubber casing. At tanker berths, permit-to-work and gas-free rules decide what can be entered: cargo tanks are gauged only when the ship is gas-free, while deck structure, pump rooms and segregated ballast tanks are usually accessible once the permits are in place.

At anchor, the limits are launch access, the weather in the Strait and how long the ship will stay. A strong Levante, the easterly wind funnelled through the Strait, can make boarding from a launch difficult or suspend it altogether, so anchorage jobs need some float in the plan. The ultrasonic gauges and magnetic particle kit travel with the technicians and go aboard by launch, so no shore equipment is needed. When the scope grows to a full survey programme, combining afloat work in Algeciras with the remaining measurements at a nearby drydock usually makes the best use of the ship's time.

• APM Terminals Algeciras and the Isla Verde Exterior container terminal — scrubber piping, engine-room tank and void gauging on mainline ships during relay calls
• Algeciras Bay anchorages — bunkering and waiting stays used for targeted gauging, pre-purchase sampling and crack detection at known fatigue details
• Tanker berths serving the San Roque refinery — deck, pump room and segregated ballast readings for crude and product tankers, subject to the terminal's permit rules
• Ro-pax berths at Algeciras and Tarifa — car-deck, ramp and ballast tank gauging during lay-overs or off-season maintenance periods
• Drydocks at Gibraltar and in the Bay of Cádiz — where gauging started in Algeciras can be completed alongside the docking survey

Port state control, the Med ECA and transhipment economics

Spain is a Paris MoU state, and port state control inspections in Algeciras are carried out by inspectors of the Capitanía Marítima, the harbour-master authority of the Spanish maritime administration. Structural corrosion found during an inspection — wasted deck plating, holed air pipes or a thinned fire main — can lead to a detention, and owners then need gauging at short notice so that class and the flag can decide on repairs. Since 1 May 2025 the bay has been inside the Mediterranean SOx ECA established under MARPOL Annex VI regulation 14: ships without scrubbers burn 0.10% sulphur fuel, while scrubber-equipped ships keep their systems running, and their wash-water piping keeps corroding.

Commercially, Algeciras competes with Tanger Med across the Strait for the same transhipment business. With EU ETS covering shipping since 2024 and FuelEU Maritime since 2025, carriers now weigh emissions exposure as well as port time when they plan relays, and the outcome decides how long their ships spend in the bay. For technical managers this has a practical effect: a mainline vessel's Algeciras call is usually tight, but feeders, ships waiting for a slot and vessels laid by between rotations can offer a usable window for inspection, provided the gauging plan is ready before the ship arrives.

Since 1 May 2025 the whole Mediterranean has been a sulphur emission control area, so ships calling at Algeciras 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 Algeciras

A gauging job at Algeciras 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.

For Algeciras, the usual routing from India is into Málaga, Seville or Jerez through a European or Gulf hub, then by road to the bay; Gibraltar's airport is another option when UK connections suit. Terminal and jetty access goes through the ship's agent, who requests ISPS gate passes and lists the technicians for the terminal. For anchorage jobs the agent also secures a launch, timed so the technicians board as the ship starts bunkering or settles to wait. Technicians travel on Schengen visas, so the earlier we know the expected call, the more reliably the mobilisation can be fixed.

• 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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