Lifeboat air cylinder explosion on an empty installation

An air bottle exploded on a lifeboat causing significant damage. The damage was discovered during a periodic inspection of an offshore platform which had been shut-in and had no crew on board. As the damage occurred on an uncrewed installation, there were no injuries or fatalities, but also no witnesses to the event or an exact date/time when it occurred.

The affected lifeboat was removed and taken ashore for further inspection. One of the bottles had exploded with a good portion of it propelling upward through the centreline seating structure and embedded itself into the overhead of the lifeboat. One bottle fell to the sea through the hole created in the hull of the boat and one bottle remained intact.

The operator coordinated with the lifeboat servicing vendor and local regulatory authorities to produce an understanding as to the probable cause of the incident. The following points were noted:

• The bottles in this boat were purchased new in 2018.
  
  
• Further inspection after the lifeboat was brought onshore revealed significant corrosion over the length of the bottles in the area where they were in contact with the bottom of the boat.
  
  
• Each of the three bottles was placed in a form fitting “saddle” built into the bottom structure of the lifeboat instead of being raised slightly above the deck in a cradle. The two brackets holding the bottles from above were made of stainless steel and there was no insulating material between this bracket and the steel bottles. It appears the installation and location of the bottles was subject to retaining moisture, especially between the bottle and the saddle. It could be that the corrosion was further exacerbated by galvanic action between the steel bottles and the uninsulated stainless-steel bracket.

Members should be aware that this could affect any lifeboat with steel air cylinders installed in the same manner.