Near-miss: Potential use of petroleum-based grease in an oxygen-rich environment
- Safety Flash
- Published on 21 June 2006
- Generated on 16 October 2025
- IMCA SF 07/06
- 2 minute read
A Member has reported a near-miss incident involving the use of hydrocarbon-based grease in an oxygen-rich environment.
What happened?
A diving supervisor had asked an electrician to remove a seized COâ‚‚ scrubber motor from a deck decompression chamber (DDC) for repair. The electrician removed the motor to the workshop, where it was dismantled, cleaned and the bearing lubricated with petroleum-based grease.
The use of petroleum-based grease on a motor to be used in an oxygen-rich environment (as on a COâ‚‚ scrubber in a diving bell) could cause self-ignition and fire, with resulting injuries or fatalities.
It was realised that petroleum grease had been used before the motor was refitted. The motor was discarded and a new motor used instead.
The following points were noted:
- The diving supervisor had not advised the electrician that petroleum-based grease should not be used.
- The electrician was unaware that petroleum-based grease was not to be used.
- The fact that grease was applied to the bearing was detected and immediately the scrubber motor was discarded.
The company involved has made the following recommendations:
- Procedures for repair or maintenance of any item should specify special requirements (if any) for that item.
- Diving/life support equipment should only be serviced by appropriately experienced and qualified personnel.
- Diving/life support equipment should always be checked by appropriately qualified personnel following repair, to ensure all appropriate service and maintenance safety precautions are taken.
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.