A chief engineer is a senior engineer in an organization. Typically they are in charge of an engineering department, and duties vary considerably depending on the industry.
In marine engineering, the chief engineer is a licensed mariner in charge of the engineering department on a merchant vessel.
A chief engineer (commonly referred to as"ChEng," "the Chief" or just "Chief") is responsible for all operations and maintenance that has to do with any and all engineering equipment throughout the entire ship.
Under most jurisdictions the chief engineer is of equal rank to the captain, with responsibility being split between the two posts; the chief engineer taking responsibility for engine room and maintenance, and the captain taking responsibility for navigation and deck operations.
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