The most junior watchkeeping engineer officer, gaining experience under supervision of senior engineers.
In practice
The role is primarily developmental: the fourth engineer works closely with the second engineer and senior ratings to build practical understanding of all machinery systems, develops proficiency in planned maintenance systems, and accumulates the sea service required for certification progression. Under MLC 2006, work and rest hour records must be maintained for fourth engineers like all other watchkeepers, and they are entitled to the same occupational health and safety protections as senior officers. Some companies appoint cadets or engineer cadets to an equivalent role under a cadetship agreement, in which case the trainees are subject to STCW Chapter III sea service requirements for the OOW certificate.
Regulatory detail & full definition
The fourth engineer is the most junior watchkeeping engineer officer, typically certificated at the operational level under STCW III/1 (officer in charge of an engineering watch) or, in some fleets, serving as a supernumerary gaining sea service towards that certificate. The fourth engineer stands a scheduled watch — often the 8–12 or 4–8 — under the supervision of the second or third engineer, and is assigned routine maintenance tasks and machinery monitoring duties.
The role is primarily developmental: the fourth engineer works closely with the second engineer and senior ratings to build practical understanding of all machinery systems, develops proficiency in planned maintenance systems, and accumulates the sea service required for certification progression. Under MLC 2006, work and rest hour records must be maintained for fourth engineers like all other watchkeepers, and they are entitled to the same occupational health and safety protections as senior officers. Some companies appoint cadets or engineer cadets to an equivalent role under a cadetship agreement, in which case the trainees are subject to STCW Chapter III sea service requirements for the OOW certificate.