Instead of using proper transfer arrangements and the dedicated manifold pipe connections on board the transferring and receiving barges, both barges had opened up the tank manhole covers on deck, through which lengths of 100 mm diameter flexible hoses were inserted directly into the tanks. A large capacity portable pump, haphazardly located on deck near the open manhole on the transferring barge, was in operation and transfer was proceeding at a fast rate, causing a forceful discharge of vapour and air mixture through the open manhole on the receiving barge. In addition, the hoses were shoddily secured by very thin ropes.
Apparently, this hazardous transfer method was adopted to overcome the limited capacity of the barges’ normal transfer pumping and piping systems.
The following obvious dangers were totally ignored:
- Risk of explosion and fire caused by possible static electric spark from the ends of portable hoses inserted into diesel tanks;
- Inflammable air and vapour mixture freely being vented on decks from open manholes;
- Threat of spill and resulting fire and pollution hazards from lightly secured hoses;
- Health risk to personnel from diesel vapours;
- Risk of personnel falling through open manhole into diesel tanks on both barges.
Root cause/contributory factors
- Perceived slow transfer rate of dedicated pumping system on board transferring barge;
- Lack of awareness of associated multiple hazards in using improper transfer methods.
Other lessons learnt
- Inserting hoses or any other foreign objects, especially those made of materials likely to accumulate static charge, like plastics, into fuel tanks, is extremely dangerous and can ignite the flammable air-vapour mixture that almost always exists in the tank of a bunker barge.
- Barge operators must be educated in safe operational practices. Inter-barge transfers in stream must be avoided, unless absolutely necessary for safety reasons. If such inter-barge transfer must be undertaken, it must only be via the dedicated transfer piping arrangements.
Source: Mars,The Nautical Institute