A recent IMCA Safety Flash focuses on an incident in which there was a fire in a 25bar high flow diesel driven screw compressor installed on the back deck, to provide lessons learned.
The incident occurred on a diving support vessel operating within the 500m zone of a platform. The compressor was a long-term rental unit being used to provide ancillary air for subsea operations. It had been running for 30 minutes at the time of the fire, and there were no indications of anomalies leading up to the incident. The fire was extinguished quickly and safely. There were no injuries.
What went wrong?
- There was a short circuit within the compressor electrical junction box, which melted insulation on cables both inside and outside the junction box.
- The radiant heat from the melted wires compromised the integrity of a nearby oil scavenger line.
- The scavenger line end fitting parted, which released compressor oil under pressure inside the compressor cabinet. This oil ignited, causing a fire which was fed by air being drawn across the compressor by the engine cooling fan.
Compressor on deck
Damage to interior of compressor
Causal factors
- The Original equipment manufacturer (OEM) maintenance regime did not require the physical testing (i.e. insulation resistance checks) of wiring at each major service interval.
- The hired compressor was considered “standard equipment” within the company and did not require detailed pre-mobilisation inspection/surveillance activity.
- The risk assessment and management of change for the use of the compressor did not identify fire as a hazard associated with operating the equipment, and a safe use of work equipment assessment had not been completed.
Actions taken
- When procuring temporary equipment to be used in the offshore environment:
- Assess the potential fire hazard, and if applicable check the unit for in-built fire suppression capability and audible/visual alarm system set-up.
- Temporary equipment used in the offshore environment should be considered as non-standard, and procurement of such equipment should be subject to careful and appropriate checks.
- Before mobilizing mobile deck equipment onto vessels, consider the required inspection/surveillance necessary, inclusive of any run-up test and review of maintenance and operational history.
- Once temporary mobile deck equipment is mobilised, ensure that a safe use of work equipment assessment is completed.
- Deck plans should reflect the safe positioning of equipment and consider requirements for exclusion zones around adjacent equipment in event of fire.
IMCA’ s member noted that this was the fourth compressor fire incident across their offshore operations since 2018.
