Fire in diesel generator following tests
- Safety Flash
- Published on 24 July 2023
- Generated on 17 September 2025
- IMCA SF 18/23
- 2 minute read
There was a small fire in the engine room on a vessel in port.
What happened?
The incident occurred when a diesel generator was being maintained by a third-party maintenance team.
On completion of a change of alternator bearings, the generator was tested at idling speed, and no problem was found. But when the generator was tested at operational speed, after a few minutes fire came out of the non-drive end exciters.
The alarm was raised; the diesel generator was brought to an emergency stop and the fire was put out with an extinguisher.
What went wrong?
- There was a misalignment of the internal cover of the non-drive end bearing.
- This misalignment caused friction against the shaft and subsequent sparking.
- The root cause was considered to be insufficient supervision of the third-party personnel conducting the maintenance.
Lessons learnt
- Whilst there was only a burnt alternator in this case, the potential was for the fire to have spread throughout the engine room.
- Ensure full and thorough supervision of the personnel of third-party contractors.
- Check carefully the status and readiness of any equipment after maintenance and test – in this case, it was as well that they tested it at operational speed rather than only when idling.
Related Safety Flashes
-
IMCA SF 12/23
16 May 2023
-
-
IMCA SF 03/23
18 January 2023
-
-
IMCA SF 03/22
28 January 2022
-
IMCA SF 25/19
28 October 2019
-
IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.
The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.
All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.
IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.
The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.
Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.