A malfunction with an inert gas generator (IGG) on board a tanker was taken seriously by the tanker company, which adjusted its planned maintenance system (PMS) accordingly. A good example of positive action, states The Nautical Institute.
The Nautical Institute gathers reports of maritime accidents and near-misses. It then publishes these so-called Mars Reports (anonymously) to prevent other accidents from happening. A summary of this incident:
A tanker was berthed and discharging cargo when carbon shoot particles were observed on the sea side of the vessel. It was quickly identified that the shoot particles were coming from the overboard discharge of the inert gas generator (IGG) scrubber.
The discharging operation was interrupted to further investigate the cause and rectify the issue. There were no overdue maintenance, inspection or defect jobs related to the IGG and associated equipment. The vessel’s engineers found that the inert gas sampling lines to the IGG oxygen analyser were partially clogged due to carbon deposits.
The planned maintenance system (PMS) did not include any requirement for periodic inspection of the sampling pipes of the oxygen analyser. Although the likelihood of the lines becoming clogged is considered low, the company’s PMS was updated to provide for periodic checks and cleaning of inert gas sampling pipes for the oxygen analyser.
Also, the frequency of scrubber tower inspection/cleaning was changed from twelve to six months in vessels with IGGs as this could provide an early indication of systems component clogging.
Advice from The Nautical Institute
- Often, complex systems depend on a variety of small, but important components that must all function correctly in their own right for the system to operate properly. Make sure these components are included in your PMS.
- Every incident gives lessons learned, and in this case the company took positive action gleaned from their investigation. Does your company do the same?
This accident was covered in the Mars Reports, originally published as Mars 202319, that are part of Report Number 366. A selection of this Mars Report was also published in SWZ|Maritime’s May 2023 issue. The Nautical Institute compiles these reports to help prevent maritime accidents. That is why they are also published (in full) on SWZ|Maritime’s website.
More reports are needed to keep the scheme interesting and informative. All reports are read only by the Mars coordinator and are treated in the strictest confidence. To submit a report, please use the Mars report form.