13 Mr Porta was an engineer whose responsibility was to provide the methodology for the collapse of seven boilers on the BHP Newcastle site demolition site. On 19 September 2002, he was directing the induced collapse of Boiler 6, a large structure, weighing 300 tonnes and standing 31 metres in height. In preparing his calculations for the induced collapse he failed to notice that a significant structural beam, known as B11, was already removed from the boiler. Mr Porta did not recall ordering the removal of beam B11. He prepared calculations without this being taken into account.
14 Originally, the decision was made to "drop" Boiler 6 to the north. However that required the removal of a coal bunker which was in the fall path of the boiler. The coal bunker proved so heavy it could not be shifted. The excavator that had been planned to be used to assist in its removal was not available from Brambles. It was then determined to drop the boiler in another direction, that is, to the west.
15 WorkCover Authority issues permits for demolition. On 16 September 2002, Mr Porta had approval by way of a permit for the northerly drop of Boiler 6. He spoke to WorkCover on 18 September 2002 as to the proposed change of direction for the collapse of Boiler 6 to the west then faxed his amended methodology. He assumed approval and proceeded with the induced collapse to the west without the permit.
16 On 18 September 2002, Mr Porta had overseen the removal of a further cross beam, beam B1. The structure also had all ducting removed from it. Without the official permit for the drop and acting on calculations which did not take account for a missing structural cross beam B11, he ordered another beam, B12, to be removed early in the morning of 19 September 2002.
17 Mr Rees and Mr Edwards were then taken up in a cherry-picker to perform the cuts to the columns of Boiler 6. The two employees performed the top cut to the south west column to begin to create a "hinge" movement on the columns to assist in the induced collapse. They proceeded then to make the middle cut. While that was being undertaken, there was an unplanned, uncontrolled collapse of Boiler 6.
18 As a result of the incident, Mr Rees who was performing the cuts in the cherry picker high above the ground suffered fatal injury when the cherry picker was struck in the fall of Boiler 6. Mr Porta, himself, and Mr Edwards both suffered injuries.
19 From the expert reports there were a number of causes contributing to the failed collapse: beam B11 had been removed; stress calculations were incorrect; cuts were meant (in the original procedure) to be within 50 mm of the web but in the amended proposal, cuts went right up to the web of the column; there was no temporary bracing or support structure provided to ensure a "controlled" collapse.
20 The acts of omission asserted against the defendant and to which the defendant pleads guilty was his failure to provide a safe system of work through: the failure to undertake a sufficient investigation into the structure of the Boiler 6; the failure to accurately calculate the structural capacity of the columns; the failure to adequately risk assess the task and the failure to ensure the calculations took into account the state of the structure on the relevant date.
21 Mr Porta had the authority on this site to organise the demolition of Boiler 6. As a self-employed person, Mr Porta carried an absolute obligation to ensure the safety of persons who were not his employees and to ensure that such persons were not exposed to any risk arising from the conduct of his undertaking.
22 I have accepted Mr Porta's plea to the charge. I do so given the particular facts agreed to. Mr Porta while the consulting engineer was always on the work site. The BHP site at Newcastle was always his place of work and he performed his undertaking to design the methodology while at the site. It was his place of work on 19 September 2002 (as distinguished in Tsougranis v Inspector Carmody (No 2) [2006] NSWIRComm 133; see also WorkCover Authority of NSW (Inspector Farrell) v Morrison (No 1) [2001] NSWIRComm 325 and WorkCover Authority v Schrader (2002) 112 IR 284 at [64]).
23 It has been held prima facie once the warranty prescribed by s9 of the Act is breached due to the presence of a risk to the health or safety of a person who is not an employee, there is a breach of the section. It is the risk to health or safety which triggers the operation of the provision. Mr Porta was therefore obliged to exercise abundant caution and constant vigilance and take all practical precautions to ensure the safety of Mr Rees and Mr Edwards. While Mr Rees and Mr Edwards were employed by Demtech, the engineering responsibility for the demolition was Mr Porta's. He had an absolute obligation to protect the other workers.
24 While the mere occurrence of the incident or detriment to safety is not sufficient to establish an offence there was, I accept, a clear causal connection established between the acts of Mr Porta in making an error in his calculations as to the distribution and weight-bearing capacity of the columns leading to the uncontrolled collapse. Further, he failed to factor into the methodology bracing or any secondary support in Boiler 6. He did not risk assess the task. Mr Porta's acts were causally connected to the detriment, that is, to the risk to safety arising from the uncontrolled collapse which risk, in this incident, became a reality.
25 It was a serious breach of the Act, the ramifications of which caused the death of Mr Rees, which fatality must be read as reflective of the gravity of the offence. As it was held by Hill J in Tyler v Sydney Electricity (1993) 47 IR 1 (at 5):
The gravity of the damage or injury actually resulting from breach does not, of itself, dictate the amount of penalty. However, the gravity or otherwise of the potential risk flowing from breach and its foreseeability are clearly relevant as are the measure of gravity of the breach itself and the measure of culpability.