After a stipulated period spend on board ships the engineer then goes on to clear the first certificate of competency which requires attending classes and practicals at an authorized institute. Thereafter this loop of working on board for some period of time and taking exams continues, till one reaches the level of a chief engineer which is the senior most engineering position on board ships. I have deliberately omitted the specific time periods that need to be spend as that depend on various factors so no single answer would suffice but it should give a fairly good idea to the reader about marine certifications. The diagram below shows the rank hierarchy of marine engineers on board ships.

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The job profiles of these ranks are normally divided as below
- Chief Engineer – Overall incharge, administration and supervision of all ship machineries
- Second Engineer – Operational Head of all machineries and the main engine of the ship
- Third Engineer – usually in charge of Boilers, IG Plant, Generators etc
- Fourth Engineer – usually in charge of purifiers, pumps etc
- Fifth Engineer – assists the above in most operations and learns
Please keep in mind that this segregation is just a standard practice and not defined very strictly so can be somewhat different in different situations. Apart from this all engineers expect the chief engineer carry out watch-keeping in manned ships on a four-on four-off basis, while in UMS ships it is usually 8-5 working with alternative watch keeping during the UMS period. I will deal with these terms in detail separately
Hope this gives you quite a clear picture of what goes on inside the engine room but there will be lot more material so keep watching (i.e. reading). Also you can take a look at the part of a typical engine control room in the picture below which shows a panel having all sorts of gauges, switches, indications etc.

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