Fire aboard the Australian flag oil tanker Tasman

Summary

On 19 December 1998, the Australian flag tanker Tasman was alongside at No.28 wharf in the port of Melbourne where it was undergoing some modification work and survey. This included welding work in the aft peak tank.

Shortly after 1100, the duty engineer was in the control room answering alarms which indicated low generator fuel pressure. As he was turning to leave the control room, the fire alarm sounded. At about the same time, those on deck saw thick smoke issuing from the funnel and from openings around the poop deck.

The duty engineer left the control room and tried to enter the generator room with a fire extinguisher. Because of the heat he was forced to withdraw and, realising that the fire was substantial, he made for his fire station.

The 1st engineer, meanwhile, isolated the fuel to nos. 1 and 2 generators then, partly opening the forward door to the generator room, he directed a jet of water from a hose through the door toward the fire, which he could discern was burning mainly in the port aft corner of the space. The heat was such that he was unable to advance past the door.

A report was received that a shore worker was still in the aft peak tank, immediately adjacent to the scene of the fire. The 2nd engineer and an IR, both wearing breathing apparatus, descended the vertical ladder from the poop deck to the steering gear compartment to search for the man. The smoke was intense. Unable to find him in the aft peak tank, they turned their attention to the fire in the generator room. They were unaware that the shore workers had mustered on the wharf, and all had now been accounted for. At the aft entrance to the generator room, they found that, although there was still much heat and smoke, the fire appeared to have been extinguished by the hose which had been directed through the forward door.

At the forward door of the generator room, the chief and 1st engineers were continuing to hose down no. 1 generator and the port aft corner of the space. They had, by this time, been able to advance one or two metres into the generator room and, although the space was still very hot, the fire was out.

At 1118, a message was passed to the bridge that the fire was out. At about the same time, the fire brigade arrived alongside the vessel.

At 1200, after an inspection of the engine room, the fire brigade established a control position, isolating the engine room to a single point of access in order to control entry by ship's staff or others. After conducting a number of inspections with a thermal imaging camera and thoroughly ventilating the engine room, the fire brigade finally declared the space safe at 1340.

It was later found that the fire had been started by a fuel pipe on no. 1 generator, the securing screws for which had become loose allowing fuel to spray into the hot-box and leak to the bilge, before igniting on the exhaust pipes. The fire had then spread to the oil in the bilge. The fire caused some damage to no.1 generator, but the most significant damage was that sustained by electric cables in cable trays beneath the deckhead.

Conclusions

The different factors identified as contributing to the incident should not be read as apportioning blame or liability to any particular organisation or individual. These are:

1. The fire in the generator room was initiated by vibration loosening two Allen screws securing the fuel suction pipe to the no. 2 fuel pump on no. 1 generator.

2. The source of ignition of the fire could not be determined with certainty, but was most probably the exhaust manifold, the temperature of which exceeded the auto-ignition temperature of the fuel oil, and which was not sufficiently screened against spray from the engine hot box.

3. The design of the hot box was such that fuel was able to escape and flow to the bilge, where a bilge fire ensued.

4. The situation of the fuel leakage alarm, at the forward end of the engine, combined with the vessel's trim by the stern, rendered the alarm ineffective.

5. Although not conclusive, lack of evidence of interaction on the flanks of the screw threads indicates that the screws may not have been sufficiently tightened during previous assembly of the pipework. Although not contributing factors, it is further considered that:

1. When tightening up the 8 mm allen screws on the fuel system of the generators, the ship's staff had been using the incorrect torque, namely that specified for the cap nuts on the high-pressure injection pipe.
2. There was no routine in place on Tasman for recording the coming and going of personnel from ashore, with the consequence that two of the ship's staff carried out an unnecessary search for a shore worker, in a hazardous area adjacent to the fire scene.
3. The response to the fire by the ship's staff was prompt and effective.
4. The retrofit of isolating valves in the fuel supply and return lines to the generator rooms was a safety measure which proved its worth in this incident.