Oil giant Shell has confirmed all decommissioning work on the Curlew floating production vessel (FPSO) has been suspended due to an “incident” involving a worker.
The occurrence is understood to have been a “confined space incident” during tank cleaning work two weeks ago.
It has been claimed that the situation resulted in a male worker running out of oxygen while in the tank.
Shell said no one was injured.
Augean North Sea Services is carrying out cleaning and waste disposal on the FPSO at the Port of Dundee.
It will be sent to Turkey for scrapping.
The decommissioning contract was due to finish next month, but has now been pushed back to the end of November as a result.
Shell confirmed it had opened an investigation into the incident and that the Health and Safety Executive (HSE) had been informed.
A Shell spokeswoman said: “With all our operations safety is the first priority for Shell.
“We can confirm that work on the Curlew FPSO, currently berthed in Dundee at a contractor’s facility for cleaning prior to being decommissioned, has been suspended on a precautionary basis following an incident involving tank cleaning operations.
“No one was injured and the incident is being investigated.”
An HSE spokeswoman said: “We are aware of the incident and after making enquiries decided not to investigate as it does not meet HSE’s Incident Selection Criteria.”
Workers trade union Unite claimed the incident highlighted issues around “proper procedures being in place.”
John Boland, Unite regional officer, said procedures are “strong” when assets are offshore, but that the situation raises questions about what procedures are in place when a vessel is docked.
He added: “I object when incidents like this happen and it makes me wonder what health and safety procedures are in place?
“It will be interesting to see what the HSE report finds and I hope Shell will make that available when it’s complete.”
Augean North Sea Services were unavailable for comment at the time of writing.