The highest degree of watertight integrity on a ship is set by condition YOKE, which surpasses ZEBRA and XRAY in terms of security and readiness, being used in the most critical situations to maintain ship integrity.
The material condition that sets the highest degree of watertight integrity on a ship is known as YOKE. This classification is part of a system used by navies, particularly the United States Navy, which involves setting conditions for ship hatches, doors, and scuttles to ensure different levels of watertight security depending on the threat level or damage control state.
ZEBRA is another condition which is a more secure state than XRAY, but YOKE is reserved for the highest level of readiness, usually set during general quarters or when entering potentially hostile environments. It ensures that the ship can maintain its integrity even under extreme conditions, such as combat or severe weather.
So, when a ship is at YOKE condition, it is at its peak preparedness to prevent water from penetrating into unwanted areas, thus, maintaining its buoyancy and effectiveness in operations.