Final answer:
Material condition ZEBRA on a naval ship means that the ship is being secured for potential emergencies by closing watertight doors and hatches. Crew members report to preassigned posts to be ready for battle damage or other severe incidents.
Step-by-step explanation:
When an alarm for setting material condition ZEBRA is sounded on a naval ship, it indicates that the ship must be prepared for potential battle damage or other emergency situations. All personnel are required to report to their preassigned emergency stations, which may include battle stations or damage control posts. The establishment of material condition ZEBRA involves securing the ship by closing all watertight doors, hatches, and fittings to ensure the ship's integrity and maximize its survivability under attack or during other major incidents.
This response originates from naval procedures and doctrines which include protocols for dealing with uncertainty over a serious fire or hazard, and the potential for extreme physical danger. Such measures are vital for the crew's safety and the successful operation of the ship during high-risk scenarios.