3 It is agreed:
3. At all material times, the Defendant conducted business at its Port Kembla Steelworks and owned the scarfer machine and the electrostatic precipitators in the Slab Handling Department of the Port Kembla Steelworks.
4. At all material times, the Defendant employed Mr Daniel Pardy (Mr Pardy) and Mr Glenn Leake (Mr Leake) as operators in the Slab Handling Department at the Port Kembla Steelworks
5. As part of the operations within the Slab Handling Department, random slabs (approximately 5% to 10%) are oxidised by a scarfer machine to remove, or reveal, defects in the slab.
6. The scarfer machine removes approximately 2mm of material from each side of a slab by applying natural gas and oxygen at high pressure to the slab. High pressure water granulates the removed scale and blows it, and other waste (including dust), down a steel chute and into the W24 grids pit (the pit). Waste travels through grids located in the pit to a basin below the pit (with some waste caught by the grids).
7. A steel basket is at the end of the pit in which larger particles of the waste are placed by operators cleaning the pit. The basket is removed, from time to time, by a mobile crane positioned above the pit. The area from which the crane lifts the basket is covered by a steel check plate (hatch) which is situated directly above the pit.
8. The pit is linked to a dust extraction system, called an electrostatic precipitator (the precipitator), which collects and extracts dust by a system of high voltage electric charges and flushing water. The precipitator consists of 6 cells connected to the pit by a length of steel ducting.
9. Approximately 3 to 4 months prior to the incident involving Mr Pardy and Mr Leake on 21 April 2000, the Defendant commenced a program of upgrading the analogue control units in the precipitator cells to digital control units. The reason for the upgrade of the control units was to improve the efficiency of the precipitator cells as a digital system reacts to dust load fluctuations more quickly than an analogue system.
10. When operating, the precipitator produces ozone gas. However, when the scarfer machine is run out of line (that is, removed from its operating position), ozone gas should not be produced.
11. The smaller dust particles are drawn into the steel ducting and through the precipitator by an induced draft fan (ID fan). The ID fan also expels ozone gas produced by the precipitator and the cleaned gas.
12. Approximately 2 or 3 times a week (depending on the build up of waste), the pit is cleaned by operators to clear waste built up on the grids in the pit and to ensure that the waste water from the scarfer machine is able to flow into the basin below.
13. On 21 April 2000, Mr Leake decided to clean the pit. He was accompanied by another operator, Mr Pardy. Mr Pardy and Mr Leake were trained in cleaning the pit.
14. In accordance with the Defendant's isolating procedure for cleaning the grids at the pit (JI - PSH - CMS - GRIDS - 46) (the Grids 46 Procedure), Mr Pardy and Mr Leake with the assistance of an electrician isolated the scarfer machine by running it out of line, that is, removing it from its operating position. This involved isolating the Main Air (this is the air that drives the motors that move the scarfer machine) to prevent the machine coming back on line. The water pumps (SA & SB) that control the water pressure applied to the slab were also isolated.
15. Mr Pardy and Mr Leake arranged for the shift electrician to perform the electrical isolations in accordance with the Grids 46 Procedure.
16. The Grids 46 Procedure in place at the time provided that the ID fan should be switched off when the hatch is removed. However, the Grids 46 Procedure did not expressly refer to the operation of the ID fan when the hatch is in place. At the time of the incident, the hatch was in place as the basket was not required to be removed.
17. Initially Mr Leake asked for the ID fan to be isolated by an electrician. The electrician isolated the ID fan. Mr Pardy and Mr Leake sought clarification as to whether the ID fan should be isolated when the hatch was in place and consequently asked the electrician to switch the ID fan back on. The electrician switched the ID fan on by activating a switch in the electrical switch room. However, this action did not restart the ID fan as it also needed to be manually restarted by the scarfer operator in the control cabin (scarfer operators pulpit) once the power had been restored in the switch room.
18. Mr Pardy and Mr Leake checked the Grids 46 Procedure again to confirm that their actions were in accordance with the Grids 46 Procedure.
19. Mr Pardy and Mr Leake proceeded to the pit. Upon entering the pit they noticed a strong odour. However, they worked in the pit for approximately 30 minutes before Mr Pardy left the pit feeling ill. Mr Leake worked for a further 5 to 10 minutes until he also felt ill and left the pit.
20. Both Mr Pardy and Mr Leake were taken to the ambulance station. The ambulance staff cleared their return to work, however specified that they were to avoid dusty environments.
21. Immediately following the incident, the Defendant conducted atmospheric testing and monitored the air quality in the pit and in the steel ducting connecting the pit to the precipitator. The Defendant also restricted access to the pit to authorised personnel wearing breathing apparatus.
22. Further atmospheric testing was conducted at the pit under simulated conditions on 28 April 2000. An internal report dated 5 June 2000 was prepared which concluded that the level of ozone present may exceed Worksafe Australia peak levels.
23. Investigations following the incident revealed that:
(a) contrary to the understanding of Mr Pardy and Mr Leake, the ID fan was not operating despite being switched back on by the electrician in the electrical switch room; and
(b) contrary to the Defendant's understanding, cell number 4 of the precipitator continued to operate despite the scarfer machine being out of line. The investigations conducted by the Defendant after the incident revealed that precipitator cell number 4 was incorrectly wired during the upgrade program described in paragraph 9 above.
24. Following the incident a new standard operating procedure was put in place for the cleaning of the pit (SP - PSH - CMS - GRIDS - 34). The new procedure identifies the items to be isolated (after the scarfer machine is taken out of line) and expressly states:
"Precipitator cells 1-6 must be isolated and the ID fan must be on for the duration of any work where operators are on W24 grids".