H₂S leak umbilical laying
- Safety Flash
- Published on 25 January 2012
- Generated on 22 January 2026
- IMCA SF 01/12
- 1 minute read
A Member has reported an incident in which there was a H₂S (Hydrogen Sulphide) leak during umbilical laying operations.
What happened?
A deck-hand and others on deck noticed a smell of rotten eggs. Vessel management were informed, activities were halted and the area isolated. A specialist contractor was brought in to test the air for H₂S, and when the area was tested clear, operations were resumed. No-one was contaminated and no-one reported feeling sick or ill.
The following was noted:
- Owing to lack of awareness that there might be H₂S in the umbilical, there were no control measures in place.
- Appropriate tests and measurement of potential H₂S should be made before and during such umbilical deployment operations.
- If leaks are found, umbilical operations should be halted until a specialist contractor can be brought in to assist in dealing with the gas.
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.