A junior engineer officer responsible for a watchkeeping duties and maintenance of assigned machinery and systems.
In practice
The practical responsibilities of the third engineer include monitoring operating parameters of running machinery, carrying out planned maintenance tasks such as filter changes, pump overhauls, and heat exchanger cleaning, and responding to machinery alarms during the watch. Under the ISM Code, the third engineer must complete familiarisation with the SMS and all relevant emergency procedures before assuming watch duties. STCW III/1 also requires the holder to have completed basic and advanced fire fighting, elementary first aid, and survival craft training. The posting provides the foundations of engineering management skill required for progression to the second engineer certificate.
Regulatory detail & full definition
The third engineer holds a Certificate of Competency as Officer in Charge of an Engineering Watch under STCW III/1, qualifying them to maintain an unsupervised engineering watch in the machinery spaces of vessels with propulsion power above the defined threshold. The third engineer is typically assigned to the 12–4 watch and is responsible for a defined group of machinery systems — often the boilers, auxiliary engines, or refrigeration plant — whose maintenance they plan and execute under the second engineer's direction.
The practical responsibilities of the third engineer include monitoring operating parameters of running machinery, carrying out planned maintenance tasks such as filter changes, pump overhauls, and heat exchanger cleaning, and responding to machinery alarms during the watch. Under the ISM Code, the third engineer must complete familiarisation with the SMS and all relevant emergency procedures before assuming watch duties. STCW III/1 also requires the holder to have completed basic and advanced fire fighting, elementary first aid, and survival craft training. The posting provides the foundations of engineering management skill required for progression to the second engineer certificate.