Conclusion from accident investigation encourages Statoil to increase focus on vessels ex-repair yard, or with recent manning changes or shifted technical management

An LPG tanker arrived at Statoil's Kaarstoe terminal to load a full cargo of propane and butane. The vessel had just completed a three-week drydocking in Poland, with just 36 hours' steaming between the repair yard and Kaarstoe. 

The ship went direct to the loading berth to receive a batch of coolant (iso-butane). After completing the standard ship/terminal check list, the terminal loading arm was connected to ship’s manifold. A few minutes after commencing the loading, the ship’s crew heard a sharp "hissing" sound and understood they had a leak somewhere in their cargo system. An emergency shut down was initiated and soon thereafter, liquid cargo escaped from the vessel’s main riser. 

An estimated 400-500 kilos of iso-butane leaked into the atmosphere. Personnel from the vessel as well as the terminal managed to turn the liquid and vapour away from the vessel and terminal by the use of water spray. 

After the area was declared safe for entry, an inspection disclosed an open valve between a heat-exchanger and the main riser. 

When investigating the incident, the following elements were highlighted: 

-         The isolating valve between the heat exchanger and the main riser had been overlooked during re-commissioning

-         A level alarm in a knock-out drum on the line described above, was out of order

-         The vessel's crew were fatigued after 3 hectic weeks in dry-dock

-         An operational riding team could have assisted the ship's crew in the re-commissioning after the dry-dock - particularly in these circumstances where there are only a few hours between leaving the yard and reaching the loading port.

-         There were no specific valve/drain check lists developed for re-commissioning. 

A similar accident took place only 5 months ago at the same terminal and has led Statoil to increase the focus on vessels arriving from repair yards, or with recent manning changes or where the vessel has shifted technical management. 

Contact: Howard Snaith