Two P&O Ferries vessels are being inspected as the company attempts to resume normal operations after replacing nearly 800 seafarers with cheaper labour.
The Maritime and Coastguard Agency (MCA) said Port State Control (PSC) inspections are underway on European Highlander, which normally operates between Larne in Northern Ireland and Cairnryan in Scotland, and Norbay, which serves the Liverpool-Dublin route.
Among the eight vessels that are subject to inspections, two have resumed sailing, two remain under detention after failing the inspections, and two others are awaiting inspection.
A spokesperson for the MCA on Thursday said its surveyors are carrying out a full inspection of European Highlander before it returns to service “to make sure it complies with international regulations on manning and safe operation, in particular, emergency procedures such as firefighting and evacuating the ship.”