Leak in hot water system for saturation divers
- Safety Flash
- Published on 9 January 2024
- Generated on 18 June 2025
- IMCA SF 01/24
- 1 minute read
Divers Hot Water Unit had a water leak.
What happened?
During saturation diving operations between bell runs it was noted that Divers Hot Water Unit #2 had a water leak. The leak was investigated and located, but was found to be in a place with very poor access. There was a small hole in a pipe, which on investigation was found to be a bigger hole under surface corrosion.
The Dive Supervisors and Dive Superintendent were immediately informed about the issue, and diving was suspended due to there being no backup for the remaining Hot Water #1 Unit.
What went wrong?
- Due to very limited access, it was not possible to inspect the tank outlet of the 4″ closed circuit pipework.
- External corrosion had over the years completely corroded the 4mm pipe in a very limited area.
What was the cause?
- The direct cause: corrosion over many years.
- The root cause: The inaccessible location [for visual inspection] of the pipe.
The hole at 6 o’clock in the water intake
Sleeve welded at the area of corrosion
Location of the hole, inaccessible for visual inspection. Picture shows the back part of the unit mounted against a wall
Actions
- Sleeve welded on the leaky area;
- Hot Water Unit #1 was inspected and no defects found;
- Consider wall thickness measurements of old pipes.
Related Safety Flashes
-
IMCA SF 08/19
25 April 2019
-
IMCA SF 05/20
13 February 2020
-
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.