Industrial Relations Commission of New South Wales in Court Session CITATION : Rodney Morrison v Akula Pty Limited formerly known as RaiseBore Australia Pty Ltd [2004] NSWIRComm 41 PROSECUTOR Inspector Rodney Morrison PARTIES : DEFENDANT Akula Pty Limited formerly known as RaiseBore Australia Pty Ltd FILE NUMBER: IRC 2983 of 2002 CORAM: Boland J CATCHWORDS : Occupational Health and Safety - Prosecution under section 17 (1) of the Occupational Health and Safety Act 1983 - Mining industry - Person fatally injured in rock fall from ventilation shaft - Premises - Premises made available as place of work - Control - Defences under section 53 - Plea of not guilty Offence proven LEGISLATION CITED : Occupational Health and Safety Act 1983 Mines Inspection Act 1901 Federal Commissioner of Taxation v ANZ Banking Group (1979) 143 CLR 499 McMartin v Broken Hill Pty Co Ltd (2000) 100 IR 241 CASES CITED : McMillan, Britton & Kell v WorkCover Authority of New South Wales (Inspector Blake) (1999) 89 IR 464 WorkCover Authority (Inspector Ankucic) v McDonald's Australia Ltd (2000) 95 IR 383 WorkCover Authority of New South Wales (Inspector Patton) v Fletcher Constructions Australia Limited (2002) 123 IR 121 HEARING DATES: 02/16/2004; 02/17/2004; 02/18/2004; 02/19/2004 DATE OF JUDGMENT: 03/09/2004 PROSECUTOR Mr R J Burbidge QC with Mr M K Scott of counsel Solicitor: Ms B Bourke Crown Solicitors Office LEGAL REPRESENTATIVES: DEFENDANT Mr B D Hodgkinson SC with Mr M L Shume of counsel Solicitor: Mr G Phillips Carroll & O'Dea Lawyers JUDGMENT: INDUSTRIAL RELATIONS COMMISSION OF NEW SOUTH WALES IN COURT SESSION CORAM: BOLAND J Tuesday 9 March 2004 Matter No IRC 2983 of 2002 Inspector Rodney Morrison v Akula Pty Limited (formerly known as RaiseBore Australia Pty Ltd) Prosecution under section 17(1) (a) of the Occupational Health and Safety Act 1983 JUDGMENT [2004] NSWIRComm 41 1 In 1999 and 2000 Akula Pty Limited ("the defendant"), formerly known as RaiseBore Australia Pty Ltd, was contracted by Cadia Holdings Pty Limited to drill ventilation shafts at the Ridgeway Goldmine near Orange in New South Wales. The defendant, in turn, contracted with Specialised Mining Services Pty Ltd to provide the services of Nicholas Johannes Hendrick De Bruin as project manager to drill a shaft 207 metres long and about 4.5 metres in diameter identified in contractual documents as vertical riser 3 or VR3/5180. Mr De Bruin was fatally injured on 27 May 2000 whilst carrying out the contract. At the time of the incident two other persons were present; the defendant employed neither. One was slightly injured. 2 The defendant was charged with an offence under s 17(1)(a) of the Occupational Health and Safety Act 1983 by Rodney Morrison ("the prosecutor"), Assistant Director of Performance Improvement of the Department of Mineral Resources, as a person who had received the written consent of the Director General of the Department to institute the prosecution. Section 17 provides: 17 Persons in control of workplaces, plants and substances used by non-employees to ensure health and safety (1) Each person who has, to any extent, control of: (a) non-domestic premises which have been made available to persons (not being the person's employees) as a place of work, or the means of access thereto or egress therefrom, or (b) any plant or substance in any non-domestic premises which has been provided for the use or operation of persons at work (not being the person's employees), shall ensure that the premises, the means of access thereto or egress therefrom or the plant or substance, as the case may be, are or is safe and without risks to health. 3 The charge alleged that the defendant: being a person who had control of non domestic premises, (Ridgeway Gold Mine, Cadia Rd, Orange) which premises having been made available to persons as a place of work, particularly Mr Nicholas Johannes Hendrick De Bruin, Mr Shane Thomas Mooney and Mr Perry Michael Guise as at 27 May 2000, DID FAIL to ensure that the premises, the means of access to and egress from were safe and without risks to the health of those persons working at that place of work. 4 The particulars of the charge described the incident in which Mr De Bruin suffered his fatal injuries and the aftermath. Particular (n) alleged that: The defendant failed to ensure the premises, the means of access thereto or egress therefrom were without risks to the health of those persons working there in that it: i. Failed to ensure that those persons were not exposed to rocks or material falling from a height of 200 metres upon them. ii. Failed to ensure that an adequate protective cover was provided so as to protect persons from rock or other material falling from a height of up to 200 metres. iii. Failed to ensure that persons were not working in an area where the defendant knew or should have known that because of poor ground quality that there was a susceptibility for rocks or material to fall up to 200 metres in height. iv. Failed to ensure that adequate radio communications were available in the case of an emergency at the place of work. v. Failed to develop and put in place adequate emergency procedures. vi. Failed to ensure that a specific risk assessment was carried out prior to the work being undertaken on 27 May 2000. Sub-particulars (n) iv, v and vi were not pressed by the prosecutor. 5 The defendant pleaded not guilty to the charge against it. Background facts 6 The drilling of the ventilation shaft VR3/5180 (or raise) was carried out by a method referred to as raise drilling or raise boring. This involves the initial drilling from an upper level to a lower level of a pilot hole of some 35 centimetres in diameter. Once this is done a "drill string" extending from the top to the bottom level is put in place and a cutting head or reamer is attached to the end of the drill string at the lower level. Drilling is then carried out by drawing the rotating reamer head upwards along the route established by the pilot hole. 7 The top level (RL 5340) of the ventilation shaft where the drilling rig was located was some 500 metres below the surface. The bottom level was a further 207 metres further down. Directly above the top end of the shaft sat the drilling rig on a bed of concrete sitting on an earth "plug" about four to five metres deep. At the bottom level (RL 5180) the shaft ended in an excavated chamber or gallery, the entrance to which ran off the Mine's main decline running downwards from the surface to the bottom of the Mine and which carried all of the traffic through the Mine. The roof of the chamber and that of the access way or drive into the chamber was secured and regarded as safe. The top of the shaft and the walls of the shaft were not secured and there was an obvious risk of falling rock and material injuring persons working in the chamber and its immediate environs. 8 By 27 May 2000 the drilling of the shaft had been completed and what remained to be done was to disengage the reamer head from the drill string prior to its removal to the surface. Thus, immediately prior to the work being undertaken to remove the reamer head and dismantle it, the situation was that at the end of a 207 metre long drill string was attached a reamer head about 4.5 metres in diameter weighing a number of tonnes located immediately below the 4.5 metre wide shaft and hanging about half a metre above the chamber floor. 9 As it has been noted, Mr De Bruin's company, Specialised Mining Services, had been contracted by the defendant to provide Mr De Bruin as project manager for the drilling operation including demobilisation and removal of the reamer head. The defendant also contracted with Pybar Mining Services Pty Limited for the services of Mr Guise to assist Mr De Bruin. The defendant further contracted with Brandrill Limited for the services of Mr Mooney who was also to assist Mr De Bruin in the capacity of driver/operator of an Elphinstone 2900 loader, known as a "bogger". Both Mr Guise and Mr Mooney were under the direction of Mr De Bruin in his capacity as the defendant's project manager. 10 The procedure laid down by the defendant for removing the reamer head involved the following steps: ASSUMPTIONS 1. All raise cuttings have been mucked out and the drill string has been lowered to the floor of the drift. 2. Approval to enter the area at the bottom of the raise has been obtained. 3. A hot work permit is obtained if required. 4. A competent person to operate the oxy/acetylene lance. PROCEDURE a) Communication with the raisebore operator is to be established prior to the entry of any personnel into the area at the bottom of the raise. b) RaiseBore Australia Pty Ltd Project Superintendent, or his nominated representative, accompanied by a client representative shall first inspect the area around the hole collar at the bottom of the raise and ensure the ground support is adequate and the area safe for personnel to enter. c) Raisebore operator is to be informed of the work required to be completed, estimated duration and the time work will commence, and that they are not to move the head/string in any way unless clearly directed to do so by the designed (sic) person. d) The reamer head is lowered to approx. 500mm of (sic) the floor. e) At no time are any personnel to proceed beyond the raise collar and beneath the open hole. f) Where it is impractical to use a hole cover: (sic) the reamer head is to be secured by an IT or bogger by it looping a chain over a wing of the reamer. g) The reamer is towed to the front of the hole until the stem/drill string is touching the wall of the raise. h) The running of mobile equipment is to be kept to an absolute minimum in an attempt to ensure communication between personnel and the raisebore operator are clear and audible. i) The oxy/acetylene lance is used to cut the exposed side of the burn-out ring to the depth of the copper back up ring. j) Through communication with the operator the reamer is rotated through 180° and the new exposed side of the burn-out ring oxy/acetylene lanced to the copper. k) The reaming head should now be loose on the stem thread; lower the reamer to the floor, back the rod string off the reamer. l) Have the IT/Bogger drag the head away from beneath the brow. m) The Project Superintendent shall ensure all barricades and signs are in position prior to leaving the area at the bottom of the raise. n) The Project Superintendent shall inform the raisebore operator that all personnel have left the immediate area. As it will be explained, Mr De Bruin did not follow this procedure on 27 May 2000. 11 On the morning of Saturday 27 May 2000 Messrs De Bruin, Guise and Mooney proceeded into the Mine with Mr Mooney manning the bogger. In order to enter the Mine, personnel were required to leave a tag at the Mine entrance indicating they were inside the Mine. This tag was to be removed on exiting the Mine. The three men descended down the decline to the level where the shaft or raise ended. Chained to the bogger was an Overhead Protection Platform ("OHPP") that was to be used to place over the shaft's opening to guard against "scats and spalling" falling down the shaft and into the chamber whilst work was being carried out on the reamer. It was not designed for protection against rocks falling from up to 200 metres. The OHPP was of metal construction, about five metres square and weighed about five tonnes. It was to be placed in position by the bogger's bucket and held in position by the bogger's hydraulics. The OHPP had a slot in the centre where the drill string fitted. 12 The OHPP was placed in position covered by a number of light vehicle tyres (which proved to be completely inadequate) to absorb the impact of material falling on it. Mr Mooney remained in the cabin of the bogger with his safety belt on and the engine running in order that the hydraulics came into play. Messrs De Bruin and Guise then set about releasing a safety strap that connected the reamer to the drill string. This involved getting under the reamer as it hung suspended about half a metre off the ground and removing two nuts. This task was completed without incident and Mr De Bruin communicated with the raisebore operator to lower the reamer head to the ground. At this stage then the reamer head was resting on the ground directly underneath the shaft and the OHPP was in place over the mouth of the shaft, held there by the bogger's bucket. The reamer had not been pulled to the front of the hole until the drill string was touching the wall of the raise. The only part of the bogger that was underneath the shaft opening was the bucket. A steel prop that was to be used to support the arms of the bogger was not placed in position. 13 At about 12.30 pm Mr De Bruin prepared to use the oxycutting equipment he had brought with him to burn off the burn-out ring from the drill string. Mr De Bruin stepped onto the reamer head directly underneath the OHPP and was about to receive the oxy torch as Mr Guise handed it to him. At that moment there was a loud noise and a fall of rock and material from within the shaft hit the OHPP with great force. It is apparent from the evidence that the protection platform was forced downwards lifting the rear wheels of the bogger clear from the ground. Some rocks penetrated the protection platform and the impact was such that the platform buckled and welds were split. Mr De Bruin sustained serious head and body injuries probably from the combination of rock impact and the crushing effect of the OHPP approaching the reamer head upon which he was standing and where he was found with his head jammed between the cutters of the reamer. A rescue team arrived and in a display of considerable courage retrieved Mr De Bruin from beneath the shaft and placed him in an ambulance. Mr De Bruin, however, died of his injuries 12 days later. Mr Guise sustained some minor injuries as he escaped from near the shaft. Mr Mooney was not injured. Submissions of the parties 14 Mr R J Burbidge QC with Mr M K Scott of counsel appeared for the prosecutor. Mr Burbidge submitted that the prosecutor had satisfied the elements of the offence beyond reasonable doubt. It was submitted the matters it had to prove were: 1. The defendant had to an extent control of certain premises. 2. Those premises were non-domestic premises. 3. Those premises had been made available to persons not employed by the defendant. 4. The premises were made available as a place of work. 15 As to the question of control, it was submitted by the prosecutor this was an ordinary English word meaning having the power to direct. It was submitted that the defendant had the necessary power both in terms of its ability to regulate those who were permitted to enter the relevant area and power to direct as to the conduct of persons while in the relevant area. The prosecutor referred to McMillan, Britton & Kell v WorkCover Authority of New South Wales (Inspector Blake) (1999) 89 IR 464 and Federal Commissioner of Taxation v ANZ Banking Group (1979) 143 CLR 499 at 533. 16 Mr Burbidge submitted that by reason of the existence of the four factual matters listed above there was an obligation on the defendant to ensure that the premises were safe and without risks to health. It was contended that the premises comprising the place of work consisted of the drive leading into the chamber and the chamber itself, as well as the walls and roof of the 200-metre shaft. It was submitted that there was a danger present within the premises, namely that part of the premises might collapse. Accordingly, the premises were unsafe. 17 It was contend that there was a risk to persons in the chamber and that was recognised by the defendant in so far as it located an OHPP between the point from which the danger would emerge and the place within the chamber where persons were working. Mr Burbidge submitted that the defendant failed to ensure the premises were safe and without risks to the health of the three men employed to work therein. 18 Mr B D Hodgkinson SC with Mr M L Shume of counsel appeared for the defendant. It was submitted for the defendant that it was charged with an offence under s 17(1)(a) of the Act and not s 17(1)(b). Consequently, the Court had to be careful in making a proper distinction between a risk arising from premises as opposed to a risk arising from plant and systems of work. In other words, it was submitted that although the prosecutor's case referred to inadequacies of systems of work and plant, such as the OHPP and its failure to protect Mr De Bruin from the rock fall, the case the defendant had to meet related to unsafe premises. 19 In pleading not guilty to the charge, however, the principal defence relied upon by the defendant was that it did not have to any extent control of non-domestic premises within the meaning of s 17(1)(a) of the Occupational Health and Safety Act. Thus, it was the issue of control that lay at the centre of the defendant's defence. It was conceded by the defendant that there were premises, the premises were non-domestic and that premises had been made available to persons not employed by the defendant. Mr Hodgkinson submitted that for the purpose of these proceedings the "premises" were "that area of the Ridgeway Mine below the open end of the VR3 Raisebore ventilation shaft". In those circumstances, it was submitted that there was no evidence that Mr Mooney was exposed to a risk to his health or safety because at no time was he in the "premises". 20 In addressing the issue of control Mr Hodgkinson relied on McMillan, Britton & Kell at 480-481 where it was said by the Full Bench: In other words, the proper operation of the section requires, in our view, the degree of control which a defendant has over plant or substances or non-domestic premises, as the case may be, to be to the extent to which that person is able to ensure safety by guaranteeing, securing or making certain. For that reason, the applicable meaning of "control" in the context of s.17, by reference to its ordinary meaning as earlier outlined, must, it seems to us, have about it the sense of not mere "sway", "checking" or "restraint" but rather controlling in the sense of "directing action" or "command" - the ability of a person to compel corrective action to secure safety, having in mind the context and purpose of the statute, clearly seems to be necessary in order to enable safety to be ensured. If it were otherwise then the alleged controller would be simply unable to assume the strict duty cast by the section. We are satisfied that this approach to the meaning of "control" is consistent with that expressed in Rowson and Growth Securities by adopting the contextual approach stated in Australia and New Zealand Bank. It may be thought that the words "to any extent" qualify the word "control" so as to reduce or diminish the degree otherwise than as we have stated; however, and conformably with the context of the section, the phrase "to any extent, control" means no more than that the person liable being able to compel (or direct or command) to any extent. 21 The defendant's submission on control may be summarised as follows: · The evidence showed that the control of the premises as distinct from the work never came into the hands of the defendant. · The contract between the Mine owner and the defendant was a contract to perform work not to take control of any part of the premises. A consideration of the terms of the contract confirms this was the case - the contract was concerned with the execution of work by the defendant. · Under the contract the defendant was required to perform the work safely and in order to do that it was necessary for the defendant to give directions. However, the directions related to the work and not control of the premises. · At all times the Mine owner controlled the Mine and who was allowed into the Mine or any part of it. The defendant could not stop representatives of the Mine owner from coming into the premises as defined by the defendant. · The fact that the defendant could direct a person not to stand in the vicinity of the open shaft whilst work was being performed because it was unsafe to do so did not amount to control by the defendant of the premises. · The defendant had no control over the premises; the defendant could not direct a change to the premises to make them safe. · Entry into the Mine site and entry into the Mine was under the exclusive control of the Mine owner. · Mr De Bruin could not perform the work of removing the reamer head unless he obtained a hot work permit from the Mine owner. It could not, therefore, be said that Mr De Bruin, as the defendant's representative, had control of the premises. · The Mines Inspection Act 1901 provides that "The General Manager of a mine must reside in its vicinity and is responsible for the daily supervision, control and management of the mine." The Mines Inspection General Rule 1994 makes it clear that control of the mine lays in the hands of the mine's general manager and the production manager. The production manager has responsibility to ensure that operations in the mine are carried on in such a manner as to avoid danger to persons from falls of ore, rock or other substances. · The granting of access to the relevant area of the Mine did not confer upon the defendant control of that area of the Mine as would be required for the operation of s 17 of the Act. In the circumstances access was provided only to enable the work to be performed and not so as to pass "control" of that area of the Mine. · The evidence established that: Ø The Mine Owner's representative conducted regular inspections of the Mine and had the capacity to give mandatory directions in relation to any aspect of the mining operation. Ø The Mine owner had a policy for the placing of signs and taping off of areas to prohibit unauthorised entry. Permission to enter could be granted by a foreman of Brandrill or a person senior to him including the Mine owner's representatives. Ø The Mine owner had a responsibility to inspect areas of the Mine and performed this function through its employees and those of Brandrill. Ø The Mine owner had the responsibility for ensuring a safe environment within the Mine. Ø The Mine owner directed Brandrill to keep the decline free of vehicles or other objects that could inhibit its use. Ø The Mine owner had responsibility for supervising the works in the Mine and did that through its employees and Brandrill's employees. Ø The Mine owner had power to prevent a contractor at any time from undertaking work within the Mine. 22 In the alternative, Mr Hodgkinson submitted that if the Court were not satisfied as to that the defendant asserted about control then there was at least reasonable doubt about whether control had passed to the defendant and on that basis the prosecution must fail. 23 In the further alternative it was contended for the defendant that it was the Mine owner that made the premises available as a place of work and not the defendant. 24 In the event that it was found by the Court that an offence had been made out, reliance was placed on the defences under s 53 of the Act, although primarily s 53(a). In so far as s 53(a) was concerned, it was submitted that it was not reasonably practicable for the defendant to make the premises safe; that is, it was beyond the defendant's capacity to render the ventilation shaft safe. As for s 53(b), it was submitted the offence was due to causes over which the defendant had no control and against the happening of which it was impracticable for the defendant to make provision. 25 Mr Hodgkinson referred to McMartin v Broken Hill Pty Co Ltd (2000) 100 IR 241 at 245 where Grove J said: Before the defence is made out the defendant must combine his proof that the facts giving rise to what would be an offence occurred due to causes over which he had no control with a demonstration that it was impracticable for him to make provision against the happening "of which". Ordinary grammar would suggest in the wording of s 53(b) that the "happening of which" relates back to the expression "commission of the offence" rather than to the "causes". Consideration 26 Senior counsel for the defendant conceded, properly in my view, that the elements of the offence had been made out except two. These were whether the defendant had control to any extent of the non-domestic premises and whether the defendant made available the premises to persons as a place of work. If these elements were not made out beyond reasonable doubt there was no offence. 27 Before going to these two issues there is the question of what constituted the "non-domestic premises". The prosecutor contended that the premises comprising the place of work consisted of the drive leading into the chamber, the chamber itself and the 207 metre long shaft above the chamber. The defendant on the other hand contended that "the premises" was that area below the open end of the VR3 ventilation shaft. 28 The defendant's definition of the premises is, I consider, artificially confined. It limits the premises to the area immediately below the shaft. "Premises" is defined in s 4 of the Act to include "any land". It becomes necessary, therefore, to consider what were the boundaries of the "land" that could be said to constitute the "premises". Some assistance can be gained from considering what were the boundaries of the underground area that was made available as the "place of work". In my opinion, this area comprised of the chamber, the ventilation shaft above the chamber and at least that area of the drive where the bogger was located. In other words, the premises could not be an area smaller than the place of work and the evidence is quite clear as to what constituted the boundaries of the place of work. 29 The next issue is whether the defendant had, to any extent, control of the premises. McMillan Britton & Kell was a case involving consideration of s 17(1)(b). However, in WorkCover Authority (Inspector Ankucic) v McDonald's Australia Ltd (2000) 95 IR 383 the Court held that the reasoning in McMillan Britton & Kell was equally applicable to s 17(1)(a). So the question here is whether the defendant was able to compel or direct or command to ensure that the premises, as I have identified them, were safe and without risks to health. 30 The risk in this case was that rock or material might fall from the ventilation shaft and cause injury or death to persons working in other parts of the premises, that is, in the chamber or the adjacent drive where the bogger was located. The presence of the risk is highlighted by the fact that in order to protect persons from falling rocks an OHPP was put in position over the open shaft but, of course, this platform proved to be completely inadequate. 31 Was the defendant in a position where it could direct certain action to be taken to make the premises safe and without risk? In my opinion, that question must be answered in the affirmative. The defendant had a contractual obligation in relation to disconnecting the reamer head and dismantling it in order to bring it to the surface. It was required to perform this work in premises that were inherently - and known to be - unsafe given the prospect of rocks falling from the ventilation shaft. The defendant had sufficient control of the premises in which work was being carried out to ensure that the premises were safe. The control extended to the defendant through its project manager, Mr De Bruin, being in a position to either direct Mr Mooney and Mr Guise that work not proceed in the premises until the premises were made safe, that is, by ensuring that there was no risk to persons from rock falling from the ventilation shaft, or direct that certain action be taken to ensure that whilst persons were working in the premises they were not at risk by virtue of the unsafe nature of the premises. 32 Of course, Mr De Bruin did give certain directions to prevent risk from unsafe premises by directing that the OHPP be put in place. This illustrates the point that the defendant, through its project manager, did have control to some extent. But the OHPP was not designed to protect persons against what occurred on 27 May 2000 and proved to be inadequate. 33 Mr Hodgkinson submitted that the prosecution's case was essentially a case under s 17(1)(b) that plant (i.e., the OHPP) was not safe. I do not accept this was the case. What the defendant was required to ensure under s 17(1)(a) was that the premises were safe and without risks to health. An attempt was made by the defendant to make the premises safe to work in by the placing in position of the OHPP over the mouth of the shaft. That attempt was grossly inadequate in the circumstances because the OHPP did not, and was not designed to, withstand the forces of rock and other material falling from a height of up to 200 metres. In these circumstances the defendant failed to ensure the premises were safe and without risks to health. 34 The defendant's failures are particularised and I consider have been made out as follows, namely that the defendant failed to ensure that: 1. those persons working in the premises were not exposed to rocks or material falling from a height of 200 metres upon them. 2. an adequate protective cover was provided so as to protect persons from rock or other material falling from a height of up to 200 metres. 3. persons were not working in an area where the defendant knew or should have known that because of poor ground quality that there was a susceptibility for rocks or material to fall up to 200 metres in height. 35 In relation to Mr De Bruin and Mr Guise I consider there is no question that the defendant failed to ensure the premises were safe and that as a consequence, such persons were put at risk. I am not of the same opinion in relation to Mr Mooney who was some distance from the open shaft, sitting in the cabin of the loader with his seat belt on. I do not consider the charge has been made out beyond reasonable doubt in relation to Mr Mooney. 36 The defendant contended that it was the Mine owner that had control of the premises both under the contract and arising out of certain statutory obligations and that at no time did the owner relinquish that control. That may be so but it does not mean that in relation to the premises that had been made available as a place of work that the defendant was deprived of all control. That patently was not the case. 37 The defendant submitted that the defendant did not make the premises available as a place of work but rather the Mine owner made them available. Clearly, the Mine owner made the premises available as a place of work to the defendant but the defendant, in turn, made them available to Messrs De Bruin, Guise and Mooney. 38 I find the defendant is guilty of an offence under s 17(1)(a) of the Act in relation to the charge brought in these proceedings, unless it establishes a defence under s 53 of the Act. Defence under s 53 39 Section 53 of the Act provides: 53. Defence It shall be a defence to any proceedings against a person for an offence against this Act or the regulations for the person to prove that: (a) it was not reasonably practicable for the person to comply with the provision of this Act or the regulations the breach of which constituted the offence, or (b) the commission of the offence was due to causes over which the person had no control and against the happening of which it was impracticable for the person to make provision. 40 In WorkCover Authority of New South Wales (Inspector Patton) v Fletcher Constructions Australia Limited (2002) 123 IR 121 the Full Bench considered the requirements of s 53 as follows: 83 There was no question that the respondent had the requisite control over the worksite and, therefore, s53(b) does not arise. Rather, the respondent submitted it had done all that was reasonably practicable. As to what is required when considering a defence under s53(a), regard should be had to the judgment in WorkCover Authority of New South Wales (Inspector Byer) v Cleary Brothers (Bombo) Pty Ltd (2001) 110 IR 182: [87] It is evident from these authorities that what is required by s53(a) of the Act is a balancing of the nature, likelihood and gravity of the risk to safety occasioning the offence with the costs, difficulty and trouble necessary to avert the risk. At one end of the scale, it could not be reasonably practicable to take precautions against a danger which could not have been know to be in existence: see Jayne v National Coal Board [1963] 3 All ER 220 at 224 and Shannon v Comalco Aluminium Ltd at 362. Similarly, if the happening of an event is not reasonably foreseeable then it will not generally be reasonably practicable to make provision against that event: see WorkCover Authority of NSW (Inspector Mayo-Ramsay) v Maitland City Council (1998) 83 IR 362 at 381; WorkCover Authority of NSW v Kellogg (Aust) Pty Ltd at 259 and Austin Rover Ltd v Inspector of Factories at 627 per Lord Goff and at 635 - 636 per Lord Jauncey of Tullichettle. [88] At the other end of the scale, there will be cases, such as the present, in which known or obvious risks to safety exist. In these circumstances, the defendant will not have established a defence under s53(a) of the Act where it was reasonably practicable to have complied with the Act by ensuring that persons were not exposed to those risks. This may be the case because no measures were reasonably available or because measures which were available were not reasonably practicable. As has been discussed, the assessment of the reasonable practicability of those steps requires a balancing of the quantum of the risk with the sacrifice (in money, time and trouble) in adopting the measures necessary to avert the risk. In my view, where there is a known risk which entails the potential for serious injury to persons in the workplace, the defendant will generally have to demonstrate that the costs, difficulty or trouble occasioned by the measures significantly outweigh the risk. This must be done by reference to the charge as brought by the prosecutor. 84 Those passages were subsequently approved by the Full Bench in Legge v Coffey Engineering Pty Ltd (No 2) (2001) 110 IR 447 at [38] and in Bultitude v Grice at [71]. 85 It may well arise that due to the exigencies of a particular work situation, it may have been impractical to have developed a safe system of work in advance. The particular circumstance may not have been a matter that was reasonably foreseeable in the way that phrase has been used in the authorities: see Bultitude v Grice (at [68]): Reasonable foreseeability of a risk or detriment to safety is relevant to the extent that it assists in determining whether it was reasonably practicable to avoid the risk. 86 Regard should be had in this respect to the judgment in Kellogg (No.1) (adopted by the Full Bench of the Court in Kennedy-Taylor v WorkCover Authority (at 82), Genner Constructions (at [67] - [68]) and Bultitude v Grice (at [68])): To establish a defence under s53, the defendant must prove, to a civil standard, either that it was not reasonably practicable to comply with the Act or that the commission of the offence was due to causes over which the defendant had no control and against the happening of which it was impracticable to make provision: see Drake at 48-49; Sydney City Council v Coulson (1987) 21 IR 477 at 480; and Italo Australian Construction Pty Limited v Parkes (1988) 24 IR 428 at 431. So much was accepted by the defendant in this case. It is here that the question of reasonable foresight has relevance. If a defendant is able to demonstrate that the circumstances or causes of the detriment to safety constituting the offence were not reasonably foreseeable, it will generally have thereby established that it was not practicable to take measures to guard against that risk: see Jayne v National Coal Board [1963] 3 All ER 220 at 224 and Shannon v Comalco Aluminium Ltd (1986) 19 IR 358 at 363-364. In WorkCover Authority of NSW (Insp. Mayo-Ramsay) v Maitland City Council (1998) 83 IR 362 at 381, for example, Hill J commented in relation to s53: If the happening of an event is not reasonably foreseeable it is not practicable to make provision against it. When considering the matter of foreseeability, one should be careful not to substitute reasonable hindsight for reasonable foresight. This does not remove the obligation, to which I have earlier referred, of an employer to adopt a proactive approach to safety issues which seeks to discover and remedy potential risks to its employees and others. It is not a question of whether the employer did envisage a particular danger, but rather whether it should have. 41 In these proceedings the defendant contended that in relation to the defence under s 53(a), it was not reasonably practicable for the defendant to render the premises safe in that there was no practical way to render the ventilation shaft safe. It was not contended that the risk was not reasonably foreseeable. 42 It may well have been the case that the defendant could not secure the walls and roof of the ventilation shaft and thereby make it safe in the same manner as was done to secure the roof of the chamber, for instance. The defendant in these proceedings carried the civil onus of proving that it was not reasonably practicable for it to make the premises safe. But the requirement in s 17(1)(a) for a person in control of premises that is made available as a place of work to ensure the premises are safe does not mean that the only course open to the defendant in this case was to secure the walls and roof of the shaft to prevent rocks falling from it. What the defendant was required to do was make the premises safe so that persons were not exposed to risks to their health. In other words, provided the defendant took action to ensure that the persons working in the premises were not exposed to a risk from the premises, that is the premises were safe to work in, the defendant would have discharged its obligation. Options in this respect were referred to in the evidence. I am not satisfied on the balance of probabilities that it was not reasonably practicable for the defendant to comply with s 17(1)(a) of the Act. 43 It was not contested that the risk of rock falling from the ventilation shaft was reasonably foreseeable. Yet the defendant contended that it was not reasonably practicable for the defendant to render the premises safe thereby providing a defence. This is tantamount to contending that the risk was foreseeable - indeed, in this case glaringly obvious, but because it was not reasonably practicable for the defendant to make the premises safe, the defendant should be allowed its defence under s 53(a) despite the fact that persons were placed at obvious risk to their health and safety. 44 In relation to s 53(b) I do not accept the defendant's contentions. For the reasons I have already expressed, the offence was due to causes over which the defendant had control and in respect of which it was practicable for it to make provision. 45 I do not consider that the defendant has established a defence under s 53 of the Act. Conclusion 46 I am satisfied beyond reasonable doubt that on 27 May 2000 the defendant, being a person who had control of non domestic premises, such premises having been made available to persons as a place of work, particularly Mr Nicholas Johannes Hendrick De Bruin, Mr Shane Thomas Mooney and Mr Perry Michael Guise, failed to ensure that the premises were safe and without risks to the health of those persons working at that place of work contrary to Section 17(1)(a) of the Occupational Health and Safety Act 1983 in the manner particularised in particulars (i), (ii) and (iii) of the charge. I will hear submissions on penalty on a date to be fixed. ________________________________ DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated.