|Type:||ENGINE ROOM FIRE|
In the morning of 17 October 1998, the Australian tanker Helix was discharging oil products at the Shell terminal berth at Pinkenba, on the Brisbane River.
At 0800, three of the ship’s crew were in the engine room, starting on a daily routine of maintenance. In the cargo control room the Mate was handing over the cargo watch to the 3rd Mate. Shortly after 0800 a fire broke out in the machinery space housing the motors and pumps for the hydraulic power units. A fire-ball travelled through the ventilation grating where the exhaust trunks penetrated the bulkhead to the main machinery space.
The three personnel in the engine room made their escape, two by way of the door to the steering flat and one by way of the encased escape from the bottom main machinery space plates. In the cargo control room, personnel heard a thump and felt a sensation through the deck. Almost simultaneously smoke filled the internal stairwell to the main deck and rolled along the deckhead.
The cargo pumps closed down automatically and the Mate directed crew on deck to close the cargo manifold valves. The fire alarm was sounded and the shore supervisor called the Queensland Fire and Rescue Authority at 0804.
The crew mustered at their fire stations. The ventilation fans and motors were stopped and all remote fuel stops were closed. Two crew, dressed in breathing apparatus, made an entry to the main machinery space from the main deck level. Although there was some smoke in the uppper level they were able to reach the machinery control room level and to then descend to the hydraulic room level. They could see an isolated piece of lagging burning outside the ventilation grille, which was extinguished using a portable extinguisher. On entering the hydraulic machinery space they found a small fire burning in one corner of the "save-all" beneath the hydraulic pump units. This too was extinguished.
The remainder of the lower levels of the engine room were checked and no fire found. Five units and a commend vehicle of the Queensland Fire and Rescue Authority arrived at 0816 and fire officers boarded the ship. At 0839 the ship was declared safe.
Damage was limited to destroyed light fittings, melted indicator and warning lights and smoke damage. Little damage was sustained to the ship’s electrical cabling.
Initial examination indicated that two screws securing the hydraulic oil filter on No .3 hydraulic unit had failed, allowing a spray of fuel to come into contact with a source of ignition, most likely the exhaust trunking of the diesel engine driving No. 3 hydraulic pump.
These conclusions identify the factors contributing to the incident and should not be taken as apportioning either blame or liability to any individual or organisation.
1. The fire was initiated by a combination of two factors: the failure of the bolts securing the pulse damper unit to the hydraulic pump, together with the failure of the supporting brackets connecting the damper to the pump body flange.
2. The failure of the bolts was initiated by fatigue crack growth due to insufficient preload (torque) upon assembly.
3. The failure of the supporting bracket was caused by vibration and inadequate design, once the weight of the HP filter unit had been added to the pulse damper.
4. Ignition of the resulting spray of hydraulic oil was, most probably, caused by oil mist contacting a hot surface on the exhaust trunking of No.3 diesel, the temperature of which was above the auto-ignition temperature of the oil.
5. The design of the installation in the hydraulic machinery room provided insufficient separation, or screening, between the pressurised components of the hydraulic system and the hot surfaces of the prime movers.
It is also considered:
6. The response by the ship’s crew was rapid and effective.
7. Evidence from this and other incidents suggests that procedures relating to entry into spaces while fires are burning, or after they are believed to have been extinguished, should be reviewed and appropriate safety measures implemented.
8. The terminal emergency procedures for calling the Queensland Fire and Emergency Services are effective and appropriate.