Certified deck rating with a minimum of 18 months sea service, competent in watchkeeping, mooring, and cargo handling.
In practice
In practice, the AB stands bridge and mooring watches, operates deck machinery such as winches and windlasses, participates in anchor work, handles mooring lines, maintains deck equipment, and assists with cargo operations. They are expected to perform maintenance tasks including chipping, scraping, painting, and wire and rope splicing. On vessels operating under ISPS Code requirements, ABs also carry out access control duties and gangway watches. The AB rating forms the core of a ship's unlicensed deck workforce and is an essential stepping-stone toward officer training.
Regulatory detail & full definition
An Able Seaman (AB) is a certificated deck rating who has demonstrated a defined standard of competence in watchkeeping, seamanship, and cargo handling. Under STCW Convention regulation II/5, the certificate of proficiency for Able Seafarer Deck requires a minimum period of approved sea service — typically not less than 18 months — together with basic safety training and demonstrated practical skills. The certificate confirms the holder can keep a safe navigational watch under the direction of the officer of the watch.
In practice, the AB stands bridge and mooring watches, operates deck machinery such as winches and windlasses, participates in anchor work, handles mooring lines, maintains deck equipment, and assists with cargo operations. They are expected to perform maintenance tasks including chipping, scraping, painting, and wire and rope splicing. On vessels operating under ISPS Code requirements, ABs also carry out access control duties and gangway watches. The AB rating forms the core of a ship's unlicensed deck workforce and is an essential stepping-stone toward officer training.