Boatswain's Mate
Senior deck rating, deputy to the Bosun on larger ships; supervises deck crew, assists in cargo and safety operations.
In practice
Senior deck rating supporting the bosun. On smaller vessels the bosun's mate may also stand watches.
Regulatory detail & full definition
The boatswain's mate (bosun's mate) is a senior deck rating who acts as deputy to the boatswain on larger ships, helping to supervise the deck crew and organise mooring, cargo, maintenance and safety work on deck. It is a shipboard position rather than an STCW certificate grade, and is most common on large cargo ships and on naval and military vessels whose deck departments are large enough to need a second senior rating. The bosun's mate takes day-to-day direction from the boatswain and, through the boatswain, answers to the Chief Officer; on smaller vessels the same person may also stand navigational or gangway watches.
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Source: Industry usage
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