Fire alarm activation in engine room

What happened

There was a small fire in a vessel engine room. There was little damage and no-one was harmed. The incident occurred while a supply vessel was operating within the 500m Safety Zone of an offshore platform. An alarm appeared on the vessel’s fire alarm control panel, indicating a fire in the starboard side Engine Room cement compartment. Engineers investigated, observed white smoke and reported this to the Bridge. The Master decided to take the vessel out of the 500m zone, changed propulsion control mode to manual and then shut down the starboard main engine. The crew proceeded to muster stations. After consulting with the Master and confirming that all personnel were mustered, the fixed CO₂ system was activated by the Chief Engineer. The vessel returned to port for further investigation and repairs.

What went wrong

• The temperature sensor installed in the Starboard Shaft Generator was providing inconsistent readings since the most recent overhaul; this had not been reported by the engine crew;
• Our member highlighted two particular concerns:
  • The firefighting CO₂ suppression system remote activation failed. Further investigation revealed there was an issue with an empty pilot cylinder, potentially due to leakage in the piping between pilot and CO₂ cylinders.
  • Crew released CO₂ system while trying to tackle the fire in cement compartment. However, the cement compartment appeared not to have a CO₂ discharge point, as per vessel design, and this was not reflected  in the vessel fire training manual.

What was the cause

The smoke was caused by a failed diesel generator bearing. After disassembling the starboard shaft generator it was observed that grease in the bearing had overheated; this had generated dense white smoke.

Lessons

• Ensure crew regularly practice their knowledge on fire emergency including the activation of the fixed CO₂ fire suppression system; 
• Ensure crew are familiar with the vessel fire training manual and fire response system design;
• Review the vessel fire manual to ensure it provides an accurate overview of the vessel’s firefighting equipment functionality and relevant limitations. Any discrepancies should be reported and addressed as a priority.

Members may wish to refer to:

• Alternator bearing collapse caused small fire
• Fire in the engine room
• Incidents and events relating to C02 systems