Ultrasonic Hull Gauging on the Shannon Estuary at Foynes and Limerick

Inspection services for ships at Shannon Foynes

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

Where ships are gauged on the Shannon Estuary

There is no drydock on the estuary, so a ship that needs a docking leaves for a yard on another coast. What the estuary offers instead is long, calm berth time. At the Foynes quays a bulk carrier is typically discharged over several days, and that gives a gauging team time to work through the topside, hopper and double-bottom ballast tanks while discharge continues, then enter the cargo holds one by one as the grabs finish. Deck, hatch cover and coaming gauging can proceed alongside the cargo work wherever the stevedores have cleared the area.

At the private jetties the rules change from berth to berth. Tanker and chemical calls are bound by gas-free requirements, and work in tanks is restricted until the master and the terminal accept the certificate. Dry bulk jetties at the power stations and the refinery work to the discharge rate of the cargo, so a short stay favours a focused scope of piping, deck and a few prepared tanks. Anchorage work depends on the launch and the sea state, and is kept for ships that have already cleaned and ventilated the spaces concerned.

• Foynes deep-water quays — hold, hopper and topside tank gauging on bulk carriers during multi-day discharge, with deck and hatch coamings gauged between grab cycles.
• Foynes Island liquid bulk berths — piping, deck and released-tank gauging on product tankers, within the terminal's permit and gas-free rules.
• Aughinish refinery jetty — hull and deck gauging on bauxite and chemical carriers during the refinery's discharge programme.
• Power-station jetties at Tarbert and Moneypoint — focused deck, piping and prepared-tank gauging on fuel-supply ships alongside.
• Limerick docks — general cargo and bulk calls at the head of the estuary, where smaller ships can lie for a few days.
• Scattery Roads and estuary anchorages — launch-borne gauging of cleaned tanks on ships waiting for a berth.

Irish and EU rules affecting ships on the Shannon Estuary

Ireland is an EU member state and a Paris MoU member, and the Marine Survey Office of the Department of Transport is the body that inspects foreign ships under port state control. Bulk carriers and tankers in the estuary trades are ESP ships, so their renewal surveys and intermediate surveys call for measured thickness of tanks, holds and bulkheads at the intervals set by their class society. Older ships fixed for the Shannon trades are also likely to meet charterer scrutiny, and a clear set of recent readings helps a manager answer questions before they turn into delays.

Ships calling at EU ports must carry an Inventory of Hazardous Materials under the EU Ship Recycling Regulation, and the EU's emissions trading scheme and FuelEU Maritime both apply to voyages into Irish waters. For owners of older bulk tonnage on Irish trades, those rules make a long-term steel-condition record more valuable, because decisions on whether to renew steel, retrofit or recycle the ship rest on measured wastage rather than estimates. The estuary's industrial customers, which include a refinery and generating stations, also apply their own acceptance standards to ships using their jetties.

Wherever a ship is outside a sulphur emission control area, the global 0.50% sulphur cap applies, and many of the ships calling at Shannon Foynes meet it with an exhaust gas cleaning system rather than compliant fuel. Scrubber wash-water piping, the overboard discharge and the hull penetration around it corrode quickly in service, especially on open-loop systems, and are worth adding to the gauging scope.

How a thickness measurement job runs at Shannon Foynes

Most of the work on a Shannon Foynes job happens before the team boards: scope, plan and access are settled first, so the time on board goes on measurement.

Shannon Airport is the nearest international airport, and Dublin and Cork are the usual alternatives for long-haul arrivals, followed by a road transfer. Technicians travel from India on Irish visas, which are separate from the Schengen visa and are applied for once the ship's schedule is known. Access to the Foynes quays and to the private jetties is arranged through the ship's agent, and anchorage launches are booked by the same route, with the plan allowing a margin for late arrivals and weather.

• 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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