A chief mate (C/M) or chief officer, usually also synonymous with the first mate or first officer (except on passenger liners, which often carry both), is a licensed member and head of the deck department of a merchant ship.
The chief mate is customarily a watch-stander and is in charge of the ship's cargo and deck crew. The actual title used will vary by ship's employment, by type of ship, by nationality, and by trade. Informally, the Chief Mate will often simply be called «The Mate». The term «Chief Mate» is not usually used in the Commonwealth, although Chief Officer and First Mate are.
The chief mate is responsible to the Captain for the safety and security of the ship. Responsibilities include the crew's welfare and training in areas such as safety, firefighting, search and rescue.
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