The official daily record maintained by the engine department of machinery performance, fuel consumption, and maintenance events.
In practice
For an engineer officer, the log is both an operational tool and a compliance record. Fuel oil consumption figures must be consistent with bunkering records and cargo documentation. Oily water separator operation and bilge pump use must be recorded and cross-referenced with the Oil Record Book. Any machinery failure that affected the vessel's ability to manoeuvre or maintain the prescribed speed must be noted, as this information is legally significant if an incident occurs.
Regulatory detail & full definition
The engine room log is the official daily record maintained by the engine department, recording machinery operations, performance data, fuel and lubricating oil consumption, maintenance carried out, and any equipment failures or unusual occurrences. It is maintained watch-by-watch by the officer of the watch in the engine room, and the chief engineer is responsible for its accuracy and completeness. Like the deck log, it is a legal document.
For an engineer officer, the log is both an operational tool and a compliance record. Fuel oil consumption figures must be consistent with bunkering records and cargo documentation. Oily water separator operation and bilge pump use must be recorded and cross-referenced with the Oil Record Book. Any machinery failure that affected the vessel's ability to manoeuvre or maintain the prescribed speed must be noted, as this information is legally significant if an incident occurs.
Port state control inspectors review the engine log when investigating potential MARPOL violations, verifying separator use, or assessing whether a machinery casualty was foreseeable and preventable. The log is also used in class society surveys to verify that maintenance has been carried out in accordance with the planned maintenance system. Officers must never pre-fill log entries or complete entries in advance of the watch they purport to cover, as this constitutes falsification of a legal record.