Third Engineer
F3. Seafaring Life, Education, Professions and InstitutionsDefinition
Engine-room officer below the second engineer.
The third engineer is an engine-room watchkeeping officer below the second engineer, holding the STCW Regulation III/1 engineer officer of the watch Certificate of Competency. Typical responsibilities include the boilers, fuel and lube-oil purifiers, and assigned auxiliary machinery, plus a share of the engine watch. The rank sits above junior engineer and is an operational-level grade on the path to second engineer.
Source: STCW Code Table A-III/1