Question 1818 Deck Safety

The correct answer is D) drilling or sonic-testing the hull to determine the plate thickness. During a dry dock inspection, the hull of the vessel is belt-gauged, which involves using ultrasonic or sonic testing methods to measure the thickness of the hull plates. This process allows the inspectors to identify any significant metal wastage or corrosion that may have occurred on the hull, which is crucial for ensuring the structural integrity and safety of the vessel. The other options are incorrect because they do not accurately describe the belt-gauging process. Option A is measuring the thickness of the tail shaft liner, which is a different component. Option B is taking the vessel's offsets, which is a process of measuring the hull shape, not the plate thickness. Option C is testing the anchor cables, which is a separate inspection task not related to belt-gauging.