What does 'overhaul' mean in the realm of marine engineering?

In marine engineering, 'overhaul' refers specifically to the comprehensive process of revising and repairing machinery to restore it to good working condition. This involves disassembling parts, inspecting them for wear or damage, and making necessary repairs or replacements to ensure that the machinery operates efficiently and safely. Overhauling is crucial to maintaining the reliability and performance of equipment on board a vessel, extending its operational lifespan and preventing unexpected failures.

The other options relate to different maintenance activities. Cleaning a ship's hull is part of routine maintenance but does not involve the extensive examination and repair associated with an overhaul. Installing new machinery is more about replacement rather than the restorative nature of an overhaul. Routine checks for safety compliance focus on ensuring that equipment meets regulatory standards but lack the in-depth mechanical work that is characteristic of an overhaul. Thus, option C encapsulates the authentic definition of what 'overhaul' means in the context of marine engineering.