Industrial Relations Commission of New South Wales in Court Session CITATION : WorkCover Authority of NSW v Howard & Sons Fireworks Spectaculars Pty Limited [2000] NSWIRComm 211 PROSECUTION: PARTIES : WorkCover Authority of NSW (Inspector Robins) DEFENDANT: Howard & Sons Fireworks Spectaculars Pty Limited FILE NUMBER: IRC 839 of 1999 CORAM: Boland J CATCHWORDS : Occupational health and safety - prosecution under s 16(1) of the Occupational Health and Safety Act 1983 (NSW) - injuries to spectator from fireworks shell that failed to explode - plea of not guilty - whether particulars of charge limited the offence to one spectator - elements of s 16(1) - failure to observe minimum safety distances - defences under s 53 of OH& S Act not made out - offence proven Dangerous Goods Act 1975 LEGISLATION CITED : Dangerous Goods Regulation 1978 Occupational Health and Safety Act 1983 Carrington Slipways v Callaghan (1985) 11 IR 467 Drake Personnel Ltd t/as Drake Industrial v WorkCover Authority of NSW (Inspector James Swee Ch'ng) (1999) 90 IR 432 Environment Protection Authority v Sydney Water Corporation Ltd (1997) 98 A Crim R 481 Ferguson v Nelmac Pty Ltd (1999) 92 IR 188 Haynes v CI & D Manufacturing Pty Ltd (1995) 60 IR 149 Italo Australian Construction Pty Ltd v Parkes (1988) 24 IR 428 CASES CITED : Shannon v Comalco Aluminium Limited (1986) 19 IR 358 Sydney City Council v Coulson (1987) 21 IR 477 WorkCover Authority of NSW v Fernz Construction Materials Ltd (1999) 91 IR 119 WorkCover Authority of NSW (Inspector Glass) v Kellogg (Aust) Pty Ltd 2000 NSWIRComm 53 WorkCover Authority of NSW (Inspector Keenan) v Technical and Further Education Commission (1999) 92 IR 251 WorkCover Authority of NSW (Inspector Page) v Woolworths Limited (unreported, Peterson J, 9 September 1994) WorkCover Authority of NSW (Inspector Reid) v CSR Limited t/as CSR Wood Panels (unreported, Bauer J, 10 August 1995) HEARING DATES: 09/04/2000; 09/05/2000; 09/06/2000 DATE OF JUDGMENT: 10/31/2000 PROSECUTOR: Mr S Crawshaw S.C. with Mr B. Docking of counsel Solicitor: Ms J Wright Jones Staff & Co LEGAL REPRESENTATIVES: DEFENDANT: Mr D Day of counsel Solicitor: Mr P Bird Kenny Spring Solicitors JUDGMENT: - 1 - INDUSTRIAL RELATIONS COMMISSION OF NEW SOUTH WALES IN COURT SESSION CORAM: BOLAND J DATE: 31 October 2000 Matter No IRC 839 of 1999 WORKCOVER AUTHORITY OF NEW SOUTH WALES V HOWARD AND SONS FIREWORKS SPECTACULARS PTY LTD Prosecution under s 16(1) of the Occupational Health and Safety Act 1983 JUDGMENT Introduction 1 Howard and Sons Fireworks Spectaculars Pty Ltd ("the defendant") is a company incorporated in New South Wales. The defendant carries on the business of setting up and carrying out fireworks displays. On 28 February 1997, pursuant to a contract with the Newcastle Agricultural, Horticultural and Industrial Association Incorporated, the defendant conducted a fireworks display at the Newcastle Showground. At about 10.30 pm, in the course of a high level fireworks display a spectator, Judith Westphal, was hit by an unexploded fireworks shell on the left side of her face. Ms Westphal sustained severe injuries to her face and left eye. The Alleged Offence 2 A prosecution was instituted against the defendant by Senior Inspector Steven Robins of the WorkCover Authority of New South Wales for an alleged breach of s 16(1) of the Occupational Health and Safety Act 1983 ("the Act"). 3 The charge against the defendant was that "it did fail to ensure that persons not in its employment were not exposed to risks to their health and safety arising from the conduct of the defendant's undertaking, while they were in the defendant's place of work." The particulars of the charge were as follows: 1. The defendant was at all material times was incorporated in New South Wales having its registered address at 4th Floor, 460 Church Street, North Parramatta in the State of New South Wales. 2. The defendant was, at all material times, an employer engaged in the business of setting up and carrying out fireworks' displays. 3. On 18th February, 1997, the defendant entered into a contract with the Newcastle Agricultural, Horticultural and Industrial Association Inc. to provide a fireworks' display on 27th and 28th February and 1st March, 1997 at the Newcastle Showground which is located at Broadmeadow in the State of New South Wales. 4. On 28 February, 1997, at approximately 10.30 p.m., Judith Westphal, a person not in the employ of the defendant, was standing between the general grandstand and the members' grandstand of the Newcastle Showground, approximately one to three metres behind the show ring fence to view a fireworks display put on by the defendant. There was a short delay in the high level fireworks' display towards the end of the entire fireworks' exhibition, approximately the same time as the ground level fireworks' display was initiated. At this time, an undetonated fireworks' shell struck Judith Westphal on the lefthand side of her face, causing her injury. 5. The fireworks' shell that struck Judith Westphal was a Thunder Bird brand TB84-308 fireworks' shell, measuring 100 mm which the defendant had purchased from Hop Kee Pyrotechnics, a company engaged in the manufacture of fireworks located in China. 6. The defendant was aware that on previous occasions, fireworks' shells had not burst. 7. The system of work used by the defendant for providing the fireworks' display on 28 February, 1997 commenced with a site inspection to determine safety distances between the proposed firing point and spectators, which in turn determined what fireworks would be used for the exhibition. The fireworks were then prepared at either the firing point or on trailers, depending upon the location of the proposed firing point and the pre-fireworks' display activities around the proposed firing point. 8. The safety distances used by the defendant to determine maximum shell size for a display are from the WorkCover Authority of New South Wales Dangerous Goods Publication DG108 "Fireworks Displays" and the Draft Australian Standards DR96479 "Explosives Part 4: Pyrotechnics - Outdoor Display". The defendant used the aforementioned documents to set up a fireworks' display so that a fireworks' shell which fails to burst does not result in injury to spectators even though these were distances formulated for correctly functioning fireworks, not for fireworks' shells which fail to burst 9. The defendant did not use any instrumentation to verify the angle which a fireworks shell is launched from a mortar. As the angle that the mortars are fixed to the trailer and the angle the trailer are set to are estimated. (sic) Without verification of the firing angle and hence potential trajectory of the fireworks' shell, safety distances to spectators from fireworks' shells which fail to burst cannot be determined. 10. The defendant failed to ensure that persons not in its employment were not exposed to risks to their health and safety arising from the conduct of the defendant's undertaking, while they are in the defendant's place of work in that the defendant: (i) Failed to apply distances between the firing point and spectators which minimised the risk of spectators being injured by malfunctioning fireworks; (ii) Failed to have an adequate system of work for determining the firing angle and hence potential trajectory of the fireworks' shell; (iii) Failed to determine the distance that a fireworks' shell, which fails to burst, will travel for a given lift charge and set mortar angle, with the knowledge that fireworks' shells may misfire. 11. As a result of the defendant's failure to ensure that persons not in its employment, namely Judith Westphal, are not exposed to risks to their health or safety arising from the conduct of the undertaking while they are at its place of work, Judith Westphal sustained the following injuries: (i) major fractures from above her eyebrow and down to her jawline including her teeth and from the lefthand side of her face to her nose; (ii) broken cheekbone; (iii) squashed left eye, causing the lens to pop out; (iv) teeth pushed out of alignment; (v) badly broken bones around her left eye, most of them shattered; (vi) broken nose. 4 Mr S Crawshaw, Senior Counsel, with Mr B D Docking of counsel appeared for the prosecution. Mr D Day of counsel appeared for the defendant. Sketch of Incident 5 Set out in Annexure 1 is a sketch of the Newcastle Showground arena, the main buildings surrounding the arena and various other information relating to the alleged offence. The sketch is not to scale but it helps to explain the location of buildings, the location of Ms Westphal in relation to the point from which the shell that hit her was fired, the direction in which the shell was fired, the direction of North, the wind direction on the evening of 28 February 1997 and some relevant distances. Witnesses 6 Evidence was called from the following witnesses: 1. Senior Inspector Steven William Robins of the WorkCover Authority of New South Wales, the Informant; 2. Judith Westphal, the spectator injured by an undetonated fireworks shell; 3. Graeme Robert Sharpe, a spectator at the fireworks display who was standing with his wife close to where Ms Westphal was standing at the time she was injured; 4. Michelle Louise Ferguson, a spectator, who was attending the Showground as part of a line dancing group together with Ms Westphal; 5. Ernest Harold Brent, Safety Inspector employed by the WorkCover Authority of New South Wales; 6. Dudley Robert Saddington, Ringmaster of the Newcastle Show on the night of 28 February 1997; 7. Alexander Herbert Mandl, expert witness called by the prosecution; 8. Christian Anthony Howard, Director of the defendant and the person in charge of the fireworks display on 28 February 1997; 9. Michael Robert Lawrie, employed by the defendant on 28 February 1997 as an operator assisting Christian Howard; 10. Anthony Roland Green, senior lecturer in the School of Safety Science at the University of New South Wales and an expert witness called by the defendant. Facts 7 Most of the facts in this matter were not in issue. The relevant facts as I find them are set out below: 1. The defendant was a company incorporated in New South Wales and it was admitted that the defendant was also an employer; 2. The Informant, Senior Inspector Robins, was an inspector appointed pursuant to s 31 of the Act; 3. The defendant contracted with the Newcastle Agricultural, Horticultural and Industrial Association Inc. to provide a fireworks display on 27 and 28 February and 1 March, 1997 at the Newcastle Showground; 4. Christian Howard, a Director of the defendant, was in charge of the fireworks display conducted during the evening of 28 February 1997. He was assisted by an employee of the defendant, Michael Lawrie; 5. At the time he conducted the fireworks display at the Newcastle Showground, Christian Howard held a current Display Fireworks General Permit issued in accordance with the Dangerous Goods Act 1975 and the Dangerous Goods Regulation 1978; 6. Christian Howard had conducted between 400-500 fireworks displays prior to the display at Newcastle; 7. In or about November 1996 Andrew Howard, another Director of the defendant, carried out a site inspection of the Newcastle Showground in preparation for the fireworks display. Andrew Howard also designed the display having regard to, amongst other things, the size of the arena at the Showground. Andrew Howard was unable to conduct the display and Christian Howard, having been briefed by Andrew, undertook the task; 8. The fireworks display consisted of a ground display and an aerial display. The finale of the display was a high level aerial display; 9. The aerial display was launched from a towable, double axle box trailer acknowledged as suitable for the purpose. Approved mortar tubes were placed vertical in the trailer and wedged in with wooden wedges. The trailer was situated in the centre of the arena. The trailer had a jockey wheel situated in the mid-front of the trailer. By turning the handle on the jockey wheel the front and rear end of the trailer could be raised or lowered. At the two rear corners of the trailer were situated two jockey pads, both which could be raised or lowered so that in conjunction with the front jockey wheel the level of the front and rear ends of the trailer could be raised or lowered and the trailer made into a stable platform. By these mechanisms the angle of the mortar tubes wedged into the trailer could be increased or decreased from the vertical. The trailer could also be moved so that it faced any direction; 10. On the night in question the front end of the trailer was facing north-east and following the testing of wind speed and direction by firing comets to a height of 200 metres, and watching flags around the arena which were about bursting height, Christian Howard set the angle of the mortar tubes at an angle of somewhere between five and ten degrees from the vertical in a north easterly direction. As Mr Crawshaw said "The idea was that by shooting at an angle into the north-east wind, that the fireworks would then be blown back by the wind, that was a north-easterly wind, and would come back somewhere in the vicinity of where they were being fired from." 11. Mr Howard did not use any instruments to set the angle of the mortar tubes and relied solely on visual estimation. Mr Howard agreed under cross examination that he could not be absolutely certain that the angle at which he set the mortar tubes was five degrees or even 15 degrees but he said he determined the angle "from prior knowledge of shooting shells." In relation to wind speed and direction, the evidence was that wind readings taken at Nobby's Lighthouse, approximately 10 kilometres from Newcastle Showground, at 2200 and 2300 hours on 28 February 1997 were north-east at 10 knots and north-north-east at 11 knots, respectively. At the time of the accident Ms Westphal's evidence was that the wind was "just a gentle sort of breeze"; 12. It will be noted from the sketch that the direction of firing was away from the position in which Ms Westphal was standing. The angle between the point of aim and Ms Westphal's position was about 135 degrees in an anti-clockwise direction; 13. The distance between the firing point and Ms Westphal was about 84 metres. The distance from the firing point to the north-eastern fence of the arena was about 62 metres; 14. The calibre or diameter of the aerial shells containing the fireworks used on the evening of 28 February 1997 were variously 2.5 inches (60 mm), 3 inches (75 mm) and 4 inches (100 mm). The 60 mm shells travelled to a height of about 60 metres before exploding, the 75 mm shells a height of about 90 metres and the 100 mm shells about 120 metres; 15. The calibre of the shell that hit Ms Westphal and caused her injuries at about 10.30 pm on 28 February 1997 was 100 mm. The shell was a Thunderbird brand TBB4/308 manufactured in China by Hop Kee Pyrotechnics and was owned by the defendant. The shell failed to explode. The reason why the shell malfunctioned is not definitely known. The reasons speculated for the malfunction were that the fuse simply went out or, alternatively, the shell in question was struck by another shell in flight thereby extinguishing the fuse; 16. Christian Howard was aware that aerial shells could misfire or malfunction and fail to burst. However, since 28 February 1997 the defendant had fired some 12,000 100 mm shells and had not experienced any failures; 17. The defendant had no information from the manufacturer or supplier of the 100 mm shell which indicated the distance that a shell which fails to burst will travel for a given lift charge and set mortar angle. The defendant relied on the minimum safety distances listed in a draft Australian Standard DR96479 "Explosives. Part 4: Pyrotechnics - Outdoor displays" to ensure that a fireworks shell purchased from Hop Kee Pyrotechnics which fails to burst would not result in injury to spectators. 18. Table 3.2 "Minimum Safety Distances - Aerial Shells and Salutes" of the draft Australian Standard DR96479 provided that the minimum safety distance from the firing point to spectators for a 100 mm aerial shell or salute was 50 metres. The draft Standard also provided that: "Mortars shall be angled such that- (a) any aerial shell which has not initiated as intended will fall within the display site (or within a controlled and unoccupied area); and (b) pyrotechnic devices will not cross over or burst above any area occupied by spectators." And further that: "Notwithstanding the minimum safety distances, display fireworks shall be placed at a safe distance from spectators." 19 The Display Fireworks Permit held by Christian Howard was issued subject to compliance with the conditions in a Brochure known as DG 108 issued pursuant to the Dangerous Goods Regulation 1978. The Brochure provided that in respect of high level displays (those where fireworks are expected to reach a height in excess of 60 metres) the minimum distance for shells was "at least 50 m from the point of launch except in the direction of flight when the distance shall be 100 m. A larger distance may be required for shells over 200 mm. These must not cross over or burst above spectators." The Prosecution's Case Elements of s16(1) of the Act 8 Mr Crawshaw, who provided written submissions, identified the four elements of s 16(1) that need to be established by the prosecution, namely: a) The defendant was an employer; b) There were persons not employees of the defendant exposed to risks to their health and safety; c) The risk arose from the conduct of the undertaking of the defendant; and d) The exposure to risk was at the defendant's place of work. 9 In identifying the elements of s16(1) of the Act Mr Crawshaw relied on WorkCover Authority of NSW (Inspector Page) v Woolworths Limited (unreported, Peterson J, 9 September 1994); WorkCover Authority of NSW (Inspector Reid) v CSR Limited t/as CSR Wood Panels (unreported, Bauer J, 10 August 1995); WorkCover Authority of NSW (Inspector Keenan) v Technical and Further Education Commission (1999) 92 IR 251 (Wright J, President, Walton J, Vice President, Hungerford J). First Element 10 The first element, namely whether the defendant was an employer, was established by the evidence and admitted by counsel for the defendant. Second Element 11 The second element, Mr Crawshaw submitted had two parts to it as follows: a) There must be persons who are not employees, and b) Such persons were exposed to risks to their health and safety. 12 In relation to the first part of the second element, Mr Crawshaw referred to various pieces of evidence that established that there were persons who were not employees of the defendant. As to the second part that such persons were exposed to risks to their health and safety, Mr Crawshaw referred to WorkCover Authority of NSW v Woolworths Limited at 15; Haynes v C I & D Manufacturing Pty Ltd (1995) 60 IR 149 at 156-157 and Drake Personnel Ltd t/as Drake Industrial v WorkCover Authority of NSW (Inspector James Swee Ch'ng) (1999) 90 IR 432 at 452. Mr Crawshaw submitted that there was evidence of either or both of: "a) A potential risk to the health, safety or welfare of any or all of the spectators at the NS (Newcastle Showground) from being hit by a shell of the outdoor fireworks display being conducted by the defendant. The risk was from a malfunctioning firework including where any shell did not ignite and therefore explode or burst at the planned location, any shell that did not follow the anticipated trajectory and/or any shell that did not follow the anticipated trajectory due to a collision; b) The actual injuries suffered by the victim as a result of being hit by a fireworks shell, as particularised in paragraph 11 of the summons, " will certainly represent relevant evidence of the existence of a risk to the health and safety of (non) employees and the seriousness of that risk." Third Element 13 The third element, Mr Crawshaw submitted, also had two parts to it: a) Proof that the defendant was conducting an undertaking. b) Proof that a risk arose from this undertaking. 14 As to the first part of the third element Mr Crawshaw referred to the evidence relating to the contract between the defendant and the Newcastle Agricultural, Horticultural and Industrial Association Inc. for the conduct of an outdoors fireworks display on 28 February 1997 and the signed agreement between these two parties on 18 February 1997. 15 As to the second part of the third element Mr Crawshaw submitted that the risk arose in three ways and these are set out in Particular 10 of the Summons. Firstly, from a failure on the part of the defendant to apply distances between the firing point and spectators which minimised the risk of spectators being injured by malfunctioning fireworks. This particular failure had two parts to it: a) The failure to apply distances, without a risk to any spectator, between the firing point and any spectator within 100 metres in the direction of flight (ie., north east) referred to as area 1; b) The failure to apply distances, without risk to health and safety to any spectator, between the firing point and any spectator (including the victim), referred to as area 2. 16 Mr Crawshaw referred to various evidence to support his contention in relation to area 1. The evidence was that there were spectators within 100 metres of the firing point in the direction of flight and Mr Howard's admission that the requirement of DG 108 ( no one to be within 100 metres of the direction of flight) was not complied with on the evening of 28 February 1997. 17 In relation to area 2, which includes the area where the victim was struck, Mr Crawshaw referred to various evidence including expert evidence to the effect that, of shells that fail to burst, a certain percentage will fall outside the distances set out in the draft Australian Standard (ie., outside the minimum safety distance of 50 metres set for 100 mm shells). Mr Crawshaw also referred to the evidence from experts as to possible causes of unexploded shells falling outside the minimum safety distances. 18 The second way the risk to safety arose from the defendant's undertaking, according to Mr Crawshaw, was a failure to have an adequate system of work for determining the firing angle and hence potential trajectory of the firework's shell. The evidence included the fact that the angle of the mortar tube was set by visual estimation and no instrumentation was used to ensure accuracy. 19 The third way it was alleged that the risk arose from the defendant's undertaking was a failure to determine the distance that a fireworks shell, which failed to burst, will travel for a given lift charge and set mortar angle, with the knowledge that fireworks shells may misfire. Reliance was placed on, amongst other evidence, the report by Mr Mandl, a witness for the prosecution, which said that due to a lack of knowledge of the results of a "blind", the display operator would be unable to provide an assurance of safety to observers located within a reasonable theoretical distance from the firing point. 20 Mr Crawshaw referred to several cases as authorities for a number of propositions: a) Environment Protection Authority v Sydney Water Corporation Ltd (1997) 98 A Crim R 481 at 485: Only one of the pleaded failures or aspects need to be proved to have the requisite cause or nexus. Thus, where the charge is formulated as one involving multiple failures, the prosecutor need only prove the causal nexus between one of the failures and the risk in order to succeed. b) Carrington Slipways Pty Ltd v Callaghan (1985) 11 IR 467 at 470: The use in s15(1) of the words "shall ensure" (and it was submitted the same applies to s 16(1)) confirms the absolute nature of this offence. c) Drake at 451: It is sufficient either to show how the employer failed to provide for the health and safety of its employees or to prove the objective facts causing the detriment to safety and the causal connection to the employer's acts or omissions. d) WorkCover Authority of NSW (Inspector Penfold) v Fernz Construction Materials Ltd (1999) 91 IR 119: Proof of the commission of an offence does not require a demonstration that particular measures should have been taken to prevent the risk. Rather, it is sufficient to either show how the employer failed to provide for the health and safety of its employees or to prove the objective facts causing the detriment to safety and the causal connection to the employer's acts or omissions. 21 Mr Crawshaw submitted that the risk to health and safety was not a risk which was impossible to anticipate or that the risk was merely speculative. Evidence to support this contention included: a) Admissions by Mr Howard that it was not unknown to have misfires or malfunctions and that this included shells that failed to burst; b) Collisions occur between shells; c) On 28 February 1997 Mr Howard knew there was a possibility of shells colliding; d) The ground is checked after the display for any misfired fireworks; e) Fireworks displays do not involve precise firing systems. 22 Mr Crawshaw referred to the majority judgment in Drake at 452: "Under s15(1) the obligation of the employer is "to ensure" the health, safety and welfare of employees at work. There is no warrant for limiting the detriments to safety contemplated by that provision, to those which are reasonably foreseeable. Whilst employers are not liable for risks to safety which are merely speculative or unduly remote (see Kirkby v A & M I Hanson Pty Ltd (1994) 55 IR 40 at 50), the terms of s15(1) specify that the obligation under that section is a strict or absolute liability to ensure that employees are not exposed to risks to health or safety. It is inappropriate to seek to substitute a different test for that specified in s15(1)." 23 Mr Crawshaw submitted that the terms of s 15 and s 16 impose an obligation on an employer which is not confined to the taking of precautions only when there are warnings or signals of danger or where experience indicates that a risk to safety has arisen and requires remedy: Ferguson v Nelmac Pty Ltd (1999) 92 IR 188 at 209. Further, that WorkCover Authority of NSW v ATCO Controls Pty Ltd (1998) 82 IR 80 at 85 is authority for the proposition that the Act requires a pro-active approach and not a re-active one; employers should be on the offensive to search for, detect and eliminate, so far as it is reasonably practicable, any possible areas of risk to safety, health and welfare which may exist or occur from time to time in the workplace. Fourth Element 24 The fourth element referred to by Mr Crawshaw was the exposure to risk at the defendant's place of work. The expression "place of work" is defined in s4 of the Act to mean "premises or any other place, where persons work". Mr Crawshaw submitted that "place of work" included the fireworks display activities carried out by the defendant at the Newcastle Showground. Section53 Defence 25 Mr Crawshaw argued that the defences under s 53 of the Act were not available to the defendant. In summary, Mr Crawshaw submitted: a) If a defendant is able to demonstrate that the circumstances or causes of the detriment or risk to safety constituting the offence were not foreseeable, it will generally have thereby established that it was not practicable within the meaning of s 53(a) to take measures to guard against the risks. It is not a question of whether the employer did envisage a particular danger, but rather whether it should have. b) The greater magnitude of the risk and the greater the gravity of harm should the event occur, the higher is the duty to take precautions, even if these are expensive or difficult to adopt. c) While the likelihood of a malfunctioning shell travelling the distance it did in this case might be low, it was still foreseeable. Moreover the potential gravity of harm from a fuse failure and/or a collision and/deflection in such a fireworks shell is great. d) The defence under the first limb of s 53(b) failed because: · there would have been no detriment to health or safety had persons been kept away from the area; · it was within the defendant's power to keep persons away from the area; · the detriment turned on the remedial or preventative measures which were open and available to the defendant; · the defendant took no such action; · it was practicable to restrict access; · it was practicable to erect barricades. 26 Mr Crawshaw referred to Shannon v Comalco Auminium Limited (1986) 19 IR 358 as authority for the following propositions: a) It can be inferred that the test under s53(a) is made on the basis of the evidence before the court and is not limited by an absence of knowledge and past experience. b) Section 53 provides an objective test of what must be proved to be "not reasonably practicable". c) The standard of foreseeability is objective, but it is not necessary to show that a reasonable man placed in the defendant's position would have foreseen as a possibility the particular chain of cause and effect involved in the happening of the defendant's action. d) The absence of accidents over a long period of time does not conclude the issue of foreseeability in favour of the defendant. The Case for the Defence 27 Mr Day, for the defendant sought to deal with the prosecution's case in two ways. Firstly, by focusing on the allegations relating specifically to Ms Westphal and arguing that the failures particularised in Particular 10 of the Summons were not made out. Secondly, the allegations relating to the defendant's failure to ensure the health and safety of spectators, other than Ms Westphal, and in respect of whom the prosecution contends were within 100 metres of the firing point in breach of DG 108, are fresh allegations and not part of the charge brought in the Summons. Accordingly, the defence, having been required to meet a particular charge in the Summons, should not be required to meet a new allegation that arose during the course of the hearing. 28 As to the first part of the defendant's case, Mr Day contended that Particular 11 of the Particulars of the charge referred to "the defendant's failure to ensure that persons not in its employment, namely Judith Westphal are not exposed to risks to their health or safety arising from the conduct of the undertaking while they are at its place of work …" 29 Mr Day then referred in turn to each of the alleged failures in Particular 10 of the Particulars, namely that the defendant: "(i) Failed to apply distances between the firing point and spectators which minimised the risk of spectators being injured by malfunctioning fireworks; (ii) Failed to have an adequate system of work for determining the firing angle and hence potential trajectory of the fireworks' shell; (iii) Failed to determine the distance that a fireworks' shell, which fails to burst, will travel for a given lift charge and set mortar angle, with the knowledge that fireworks' shells may misfire." 30 In relation to the Particular 10 (i), Mr Day contended that Ms Westphal was some 84 metres from the firing point, that the mortars were not aimed in her direction but were aimed away from her and that, in terms of the angle on the azimuth, Ms Westphal was standing at a point 135 degrees away from the direction of flight of the shells. Given that the relevant minimum safety distance prescribed by both the draft Standard and DG 108 was 50 metres for the type of shell that hit Ms Westphal, the first particular had not been made out. 31 In relation to Particular 10(ii), Mr Day contended that Mr Howard was an experienced operator and, despite the absence of instrumentation, given his experience there was in fact a degree of precision involved. In any event, Mr Day contended, given that the evidence was that the most likely cause of the deviation of the shell was a collision with another shell, there was no causal nexus between the aiming system and the striking of Ms Westphal by the shell in question. 32 In relation to Particular 10(iii), Mr Day contended that given the evidence was that the most likely cause of the deviation of the shell in question was a collision with another shell then the alleged failure in Particular 10 (iii) was "irrelevant." 33 Mr Day went on to examine the probabilities of a collision, the angle of deviation and the failure to explode. Mr Day concluded that, in the context of foreseeability, the chances of these three factors coinciding to the extent they did, leading to Ms Westphal being struck by the unexploded shell, were very remote. 34 In relation to the second part of his submission Mr Day contended that the failures alleged on the part of the defendant were limited in the Summons to be in respect of Ms Westphal and not other spectators at large; that is, the charge the defendant came prepared to meet and fresh allegations cannot be made in the course of the case. 35 Mr Day submitted that if the court were against him on the particularisation of the charge, he contended that DG 108 was merely advisory and not mandatory and that the draft Australian Standard was the appropriate standard to have been applied. Given that the minimum safety distance prescribed by that standard was 50 m, the spectators on the night in question were outside the minimum safety distance and there was no failure on the part of the defendant to ensure that persons were not exposed to risks to their health and safety. 36 Mr Day also sought to rely on the defences available under s53 of the Act. His main points in this respect were: · the most likely cause of the shell to deviate was a collision coupled with a failure to explode; · the combination of the collision, the very wide angle of deviation and the failure to explode could not possibly have been foreseen; · the defendant had no control over the combination of the three factors occurring; · it was not practicable for the defendant to make provision against the causes of the incident. Consideration 37 One of the defendant's central contentions was that, according to the Summons, it was required to answer charges relating to alleged failures under s16(1) only in respect of one person, namely, the person injured on the evening of 28 February 1997, Ms Judith Westphal. The defence contended this on the basis of the wording in Particulars 10 and 11 of the particulars of the offence set out in the Summons. Mr Day said, in effect, that because Particular 11 limited the defendant's failure to Ms Westphal and that the prosecution did not word the Summons to say for example, "persons including Ms Westphal", that all the defendant should be required to answer is the charge relating to Ms Westphal. 38 The significance of this is that the prosecution alleges the defendant's failure under s 16(1) extends to and includes other spectators, in particular those within 100 metres of the firing point and who were in the line of fire to the north-east of the firing point. If Mr Day's argument were successful I would need to confine any consideration of this matter only to the alleged failure of the defendant in respect of Ms Westphal. 39 The Summons sets out the charge and what follows are eleven particulars. Particular 10 contains the essential elements of the offence as enunciated by Mr Crawshaw in his written submissions. I take the view that if I am satisfied that the prosecution has proved the elements of the offence in Particular 10 beyond reasonable doubt then the prosecution would have succeeded. Particular 11 is a separate Particular from Particular 10; Particular 11 is not required to be read in conjunction with Particular 10. 40 Indeed, it is not essential, in my view, for the prosecution to succeed, that it establish Particular 11. This is so for two reasons. Firstly, it is not necessary for the prosecution to establish every particular. What the prosecution is required to establish are the essential elements of the offence charged: Environment Protection Authority v Sydney Water Corporation Limited at 484. As I have said, the essential elements of the offence are contained in Particular 10. 41 Secondly, Particular 11 focuses not on the alleged failure of the defendant to ensure that persons not in its employment were not exposed to risks to their health and safety arising from the conduct of the defendant's undertaking (as does Particular 10), but on the consequences of the alleged failure. This, I think supports my view that Particular 11 is severable from Particular 10. Furthermore, it is not the injury, or the accident causing injury, that constitutes failure on the part of a defendant to ensure the health and safety of persons but rather it is a question of whether an employer's acts or omission created a situation of potential danger to the health and safety of persons at the place of work: Haynes at 158-159; Drake at 452. 42 Given that the essential elements of the offence are set out in Particular 10 and because Particular 11 deals essentially with consequences of the defendant's alleged failure and does not need to be established to make good the offence charged, I consider that Particular 10 can stand alone from Particular 11. 43 In the event that counsel for the defendant did prepare his case on the charges laid only in respect of Ms Westphal, he should have been alerted to the prosecution's intentions at the opening of proceedings where Mr Crawshaw said at p6 of the transcript in relation to the second element of the offence: " As to there being persons who were not employees, in the present case such persons were the spectators at the Newcastle Showground at the time in question, and those spectators, of course, included Ms Westphal the woman who was injured as a result of the misfiring shell (emphasis mine). The second part of the question as to whether the non-employees were exposed to health and safety risks will be made out, we would suggest. That risk, although by its nature only a possibility, must be a real risk and not a mere possibility, and in the present case - and we should also say it only need be a potential risk. In the present case there was a potential risk to the health, safety or welfare of any or all of the spectators at the Newcastle Showground ( emphasis mine ) from being hit by a shell at this fireworks display, and the risk arose from any malfunctioning firework which either did not ignite or collided, or for whatever reason did not burst as one would hope they would. It also includes the risk which I mentioned earlier of the trajectory of the shell deviating because of a collision. Now, although one only needs to prove a potential risk to make out the offence, the actual injuries suffered by Westphal will in themselves represent relevant evidence of the existence of such a risk, and indeed, the seriousness such a risk. 44 Mr Crawshaw also said at p7 of the transcript: "If I can go to the first of those matters, the failure to apply distances between the firing point and spectators which minimised the risk of spectators being injured by malfunctioning fireworks, this also in turn has two parts. There is a failure to apply distances without a risk to health and safety of any spectator between the firing point and any spectator in the area to the north-east, namely the area to which the fireworks were directed as a result of the wind calculations that were conducted by the defendant; and then the second failure is a failure to apply distances without a risk to the health and safety of any spectator between the firing point and any spectator, including the victim, in the area and about where Ms Westphal was injured ( emphasis mine ). Now, you will hear more, as I said, about DG108 and the minimum distances set out therein, but suffice it to say at this stage that DG108, in so far as it sets minimum distances, provides for a minimum distance of 50 metres except in the case of persons in the direction of the flight of the fireworks, where it has got to be 100 metres. You will hear evidence to this effect but the grandstand to north-east was not 100 metres distant, although Ms Westphal was more than 50 metres distant. As I said before, in relation to both DG108, the draft Australian Standard, we will be prosecuting the case in any event on the basis that those distances were merely minimum distances and did not alleviate the defendant from its responsibility, either under those standards to ensure the safety of the spectators or indeed under the Occupational Health and Act of ensuring the safety of the spectators." 45 Upon hearing these opening submissions by Mr Crawshaw, counsel for the defendant, if surprised by the references to other spectators, could have sought an adjournment or could have argued as a threshold matter that the defendant was only required to meet a charge in relation to the risk to health or safety to Ms Westphal. Mr Day chose not to do so. 46 Accordingly, I do not intend to limit my consideration of the alleged failure of the defendant to Ms Westphal. 47 As Mr Crawshaw contends, there are four elements of the offence created by s 16(1) of the Act which the prosecution is required to establish beyond reasonable doubt. These elements are: 1. That the defendant was an employer; 2. That there were persons not employees exposed to risks to their health or safety; 3. That the risks arose from the conduct of the defendant's undertaking; and 4. That the exposure to risks was at the defendant's place of work. 48 The existence of elements one, two and four were not seriously challenged by the defendant and I find that on the basis of the reasoning set out below that the prosecution has established these beyond reasonable doubt. 49 As to the first element, that the defendant was an employer, it was admitted by counsel for the defendant. 50 As to the second element, that there were persons not employees exposed to risks to their health or safety, the evidence relating to the first part of that element (that there were persons not employees) included: · the presence of Ms Westphal and other persons standing near her including Ms Ferguson, Mr Sharpe and his wife, Ms Jenkins; · Mr Saddington's evidence that he was present along with committee members and other persons on the verandah in the horse office and his evidence to the effect that there were between 10,000 and 15,000 people at the show. The people watching the fireworks display were either in the grandstands or "moving around"; · Mr Howard's evidence that there were people around the arena to the east and north-east and west and south-west of the firing point who were less than 100 metres from the firing point. 51 The second part of the second element of the offence requires the prosecution to establish exposure of persons to health or safety risks. This involves a consideration of whether the fireworks display at the Newcastle Showground on 28 February 1997 represented a risk and whether persons were exposed to that risk. That a fireworks display was conducted on 28 February 1997 at the Newcastle Showground was not in contention. Nor was the fact that 100 mm aerial shells were used, capable of reaching a height of 120 metres. The question is whether there was a potential risk to the health or safety of any or all of the spectators from being hit by an aerial shell that did not ignite and, therefore, explode before it returned to earth. 52 That it was not unknown to have misfires or malfunctions, including shells that fail to burst, was admitted by Mr Howard. It was standard procedure of the defendant following any fireworks display to check the ground for unexploded shells. Moreover, there was evidence to the effect that shells fired into the air that do not explode will not necessarily return to earth as predicted but may scatter considerable distances. 53 Exhibit Z in the proceedings was a paper presented at an International Symposium on Fireworks in Canada in May 1992 by K.L. and B.J. Kosanke. This paper was referred to by Inspector Brent in the course of his evidence for the prosecution. The paper describes experiments and the results of those experiments relating to the extent to which 'dud' aerial shells drift from the predicted path. The Abstract of the paper stated: "A prime consideration in determining separation distance requirements for aerial fireworks displays is where fallout of dangerous debris is likely to occur. Certainly the most dangerous single type of fallout is a dud aerial shell. Thus it is most important to have knowledge of where duds may fall during typical displays. This would be a relatively simple situation if aerial shells were ballistically stable, and they precisely followed the path determined by mortar orientation, shell muzzle velocity, and atmospheric conditions. Unfortunately, however, aerial shells tend to drift from their ideal (predicted path), and that drift is greater than most realize." 54 The experiments by Kosanke and Kosanke involved one 100mm spherical aerial shell falling some 114 metres from the point ballistically predicted. 55 The knowledge of the defendant that shells may fail to burst and that they tend to drift from their predicted path is, in my view, evidence that persons were exposed to risks by attending the fireworks display at Newcastle Showground on the evening of 28 February 1997. 56 Further, in Drake the majority (Wright J, President, Walton J, Vice President) at 452 said: "The occurrence of an accident and the sustaining of injuries by an employee will certainly represent relevant evidence of the existence of a risk to the health and safety of employees and the seriousness of that risk. However, it is not the accident itself which constitutes the offence, but rather the failure of the employer to ensure that its employees are not exposed to risks while at work." 57 The passage quoted from Drake applies with equal, if not greater, force to s16(1) of the Act. 58 In this case, the accident and injuries sustained by Ms Westphal are relevant evidence of the existence of a risk. This is illustrated firstly, by Mr Sharpe's evidence about the unexploded shell landing in front of him after it had hit Ms Westphal. Mr Sharpe was standing near Ms Westphal when she was hit. Mr Sharpe said: "My first recollection of the incident was when something slightly larger than a cricket ball rolled across in front of my feet. When it came to a stop, which was about a foot or 2 feet slightly towards my right foot, it had a wick and half the wick was glowing." 59 The injuries suffered by Ms Westphal are also relevant evidence of the existence of a risk to health and safety of non employees. These injuries are referred to in Particular 11 of the Summons. The fact of the injuries is contained in the evidence of Ms Westphal and in the Accident Report completed by the defendant and entered into evidence as Exhibit G. 60 I find that the second element has been established by the prosecution beyond reasonable doubt. 61 The third element is also made up of two parts, namely that the prosecution is required to establish: a) that the defendant was conducting an undertaking; b) that a risk arose from this undertaking. 62 I think that the evidence as to the defendant conducting an undertaking is clear. The undertaking was an outdoor fireworks display being conducted by the defendant in accordance with the contract or agreement with the Newcastle Agricultural, Horticultural and Industrial Association Inc. 63 The second part of the third element is far more problematic. 64 The prosecutor alleges that the risks to health or safety arose from the defendant's failure to: i) apply distances between the firing point and spectators which minimised the risk of spectators being injured by malfunctioning fireworks; ii) have an adequate system of work for determining the firing angle and hence potential trajectory of the fireworks shell; iii) determine the distance that a fireworks shell, which failed to burst, will travel for a given lift charge and set mortar angle, with the knowledge that fireworks shell may misfire. 65 As to the first alleged failure, it was argued by the prosecution that there were two aspects to it. The first related to the spectators who were not situated in the direction of flight of the aerial shells. This group of spectators included Ms Westphal and generally consisted of those persons situated on the south-western side of the arena (and I will refer to them as the "south-western spectators"). As the sketch shows, the mortars were angled some five degrees from the vertical towards the north-east whereas Ms Westphal was standing some 135 degrees on the azimuth from the direction of flight and some 84 metres from the firing point. The second aspect related to those spectators situated in the direction of flight, that is towards the north-east and within 100 metres of the firing point. These spectators were generally situated on the eastern to north-eastern side of the arena (and I will refer to these as the "north-eastern spectators"). 66 In relation to the south-western spectators, I do not accept the prosecution's contention that the defendant failed to apply distances between the firing point and spectators which minimised the risk of spectators being injured by malfunctioning fireworks. 67 In coming to this view I need to start with the question of where the mortars were pointed. While it is the case that Mr Howard did not use any instrumentation to fix the angle of the mortars and or to judge wind speed and direction, I consider that his experience over a number of years of having conducted hundreds of firings, the methods that he did use in fixing the angle of the mortars using the jockey wheels of the trailer satisfy me that the mortars were pointed in a north-easterly direction. Whether the angle of the mortars from the vertical towards the north-east was five degrees or ten degrees I do not know, but given Mr Howard's evidence and the evidence of Mr Sharpe and Ms Ferguson about where they saw the fireworks exploding and the fact that no change in wind speed was noticed by any person during the display, the angle of the mortars from the vertical could not have been significantly more than about five to ten degrees. 68 With the mortars pointing to the north-east and with Ms Westphal being situated some 135 degrees from the point of aim of the mortars, the only other matter I need to consider is the distance from the firing point to the south-western spectators. The evidence was that Ms Westphal was standing about 84 metres from the firing point. The evidence was that in setting up the fireworks display Mr Howard used the draft Australian Standard DR 96479 "Explosives and Pyrotechnics Part 4: Pyrotechnics - Outdoor Displays". That draft is now the actual Standard - AS2187.4. There was no relevant difference between the draft and the actual Standard. The draft Standard provided in Table 3.2 that the minimum safety distance between the point of launch and spectators for 100 mm aerial shells was 50 metres. 69 In his report of the accident in Exhibit F, Inspector Robins states: "The "safety distances" specified in the WorkCover Authority of New South Wales dangerous goods series publication DG108 "Fireworks Displays" and draft Australian Standard DR96479 "Explosives. Part 4: Pyrotechnics - Outdoor displays." Used by Pytec Pty Ltd and Howard and Sons Fireworks Spectaculars Pty Ltd to set up a fireworks display so that a fireworks shell, which fails to burst, does not result in injury to spectators are distances allowed for correctly functioning fireworks. These safety distances are not for fireworks shells which fail to burst." 70 The statement by Inspector Robins was, he agreed in cross examination, merely his opinion on a reading of the draft Standard. 71 Inspector Brent, in his evidence, also expressed the view as a member of the committee that prepared the draft standard, that the minimum distances set out in Table 3.2 did not apply to shells that failed to burst. 72 The draft standard also contained a 'catch-all' provision that "Notwithstanding the minimum safety distances, display fireworks shall be placed at a safe distance from spectators." The draft standard also provided that: "Mortars shall be angled such that - (a) any aerial shell which has not initiated as intended will fall within the display site (or within a controlled and unoccupied area); and (b) pyrotechnic devices will not cross over or burst above any area occupied by spectators." 73 Inspectors Robins and Brent seem to have taken the view, in their interpretation of the draft Standard, that it was the 'catch-all' provision that applied in relation to shells that failed to burst and/or the provision relating to the angling of the mortar such that any shell that fails to burst falls within the display site. 74 Inspector Brent explained in his evidence, as I understood him, that the safety distances in Table 3.2 were mandatory minima but that it was the responsibility of the fireworks display operator to set safety distances according to such factors as lift charge, wind, type of shell and in doing so ensure that any shell that failed to burst did not fall on spectators. 75 It seems to me that if a display operator was firing a 100 mm shell vertically (at 90 degrees to the ground) on a windless day and there was nothing unusual about the type of shell or lift charge that might cause it to deviate significantly from its predicted flight path, then provided the operator met the mandatory minimum of 50 metres, the operator could not, in my opinion, be said to have failed to comply with the draft Standard. On the other hand, if it was windy, for example, the operator would have to make a judgment about the angle of the mortar tube and about whether the mandatory minimum distance was sufficient. That is, the operator would have to make a judgment about how far the mandatory minimum should be extended to ensure the safety of spectators, depending on the wind strength and the direction of the wind. The operator would have to ensure that any shell that failed to burst fell within the display area (or within a controlled and unoccupied area) and that it did not hit a spectator. 76 In the present case Ms Westphal was standing about 84 metres from the point of launch - over one and a half times the mandatory minimum safety distance. The mortars were angled between five and ten degrees to the north-east. The wind was blowing no more than about ten knots - "a gentle sort of breeze." Ms Westphal was situated 135 degrees from the intended flight path of the shell. In these circumstances, if it is said that over one and a half times the mandatory safety distance was not sufficient, what should have been the minimum safety distance? I think the question is virtually unanswerable. 77 It seems to me that it would not be reasonably practicable, on the basis of the 'catch-all' provision in the draft standard, in setting a safety distance from point of launch to spectators, that an operator be required, for example, to take into account the possibility of a collision between shells after they were launched from the mortars, one shell failing to burst, deviating from its flight path by 135 degrees and hitting a spectator some 84 metres away from the point of launch. 78 The situation in relation to the north-eastern spectators is, I think, a different matter. These spectators were situated according to the evidence, in the direction of flight of the aerial shells, that is, towards the north-east. 79 It was admitted by Mr Howard that there were spectators within 100 metres of the point of launch and that they were in the direction of flight. 80 The Display Fireworks Permit issued to Mr Howard was issued subject to him complying with, amongst other things, "Brochure DG 108." 81 The Dangerous Goods Regulation 1978 provides in regulation 54(4) that: "A display fireworks permit shall be subject to the conditions specified in the permit ( including conditions which the Chief Inspector considers appropriate in the interests of the safety and welfare of the community). 82 DG 108 "gives guidance and the revised conditions to be observed for the purchase and use of display fireworks." Under the heading "Distance for Spectators" the brochure states: "The fireworks used in the display must suit the available space. For example, in a small park, shells must not be included unless it can be guaranteed that the complete zone under the trajectory of the shell, and of any falling debris, will be free of people, and that debris will not fall on any other person's property. Minimum distances are: (a) High Level Displays (ie those where fireworks are expected to reach a height in excess of 60 metres) (i) Shells - at least 50 m from the point of launch except in the direction of flight when the distance shall be 100 m. A larger distance may be required for shells over 200 mm. These must not cross over or burst above spectators." 83 In my view the defendant failed to comply with DG 108. I consider that the nature of the requirement, that spectators must be 100 metres away from the point of launch of aerial shells where they are situated in the direction of flight, is mandatory rather than advisory. It seems to me also to be a matter of commonsense. In my view this failure to comply with DG 108 created a risk to the health and safety of persons not in the employ of the defendant arising from the conduct of the defendant's undertaking. 84 The second alleged failure in Particular 10 (ii) of the Particulars in the Summons was that the defendant "Failed to have an adequate system of work for determining the firing angle and hence potential trajectory of the firework's shell." 85 I have already considered this alleged failure to some extent in relation to Particular 10 (i). 86 Even if I were to accept that there was a failure on the part of the defendant to have an adequate system of work for determining the firing angle and hence potential trajectory of the fireworks shell, I have difficulty in identifying the causal connection of that failure to a risk to health or safety. As I have earlier indicated, it cannot be said that the alleged failure to have an adequate system for determining the firing angle caused a risk to safety to the south-western spectators, including Ms Westphal. As to the north-eastern spectators situated in the direction of flight, it was the failure to apply safe distances between the firing point and spectators which created the risk to health or safety, not the failure to determine the firing angle properly. 87 Because of the particular experience of Mr Howard in setting angles by visual estimation, the special skill he has acquired through hundreds of firings of aerial shells and the particular methods used, I accept that his use of visual estimation was not a failure to properly determine the firing angle in this case. In making this finding, however, it should not be taken that I unconditionally endorse this approach as appropriate industry practice. I do not. I had no evidence before me as to what is the industry practice but I consider it would be unwise and imprudent, given the duties of employers under s16 of the Act, not to have some adequate method of measuring angles using appropriate instrumentation. 88 The third alleged failure in Particular 10 (iii) of the Summons was that the defendant failed to determine the distance that a fireworks shell, which fails to burst, will travel for a given lift charge and set mortar angle, with the knowledge that fireworks shells may misfire. 89 I think the evidence is clear on this point: Mr Howard did not know how far a fireworks shell, that failed to explode, would travel for a given lift charge and set mortar angle, knowing that fireworks shells may misfire. No steps were taken by Mr Howard to establish this information. 90 The difficulty I have again, however, with this allegation, in respect of the south-western spectators, is causal connection. Given that the evidence is that the most probable cause of the risk to health or safety to the south-western spectators was a collision that sent the shell wildly off course (see in the particular the evidence of Mr Mandl an expert witness for the prosecution), any failure on the part of the defendant to know how far a shell will travel under certain conditions does not appear to be relevant, even though the defendant knew that shells misfire. 91 In relation to the north-eastern spectators, the failure to know how far the 100mm unexploded shell would travel at a mortar angle of five to ten degrees, knowing that such shells may not explode, did create a risk to health or safety. It is axiomatic, in my view, that if an operator had set up a fireworks display according to a draft Standard that required them to angle mortars such that any aerial shell which had not initiated as intended would fall within the display site (or within a controlled and unoccupied area), it must, in order to avoid risks to health or safety of spectators, know with reasonable precision how far a given type of unexploded shell may travel in the direction of flight. 92 I find that the third element of the offence has been made out. 93 The fourth element of the offence is that the exposure to risk was at the defendant's place of work. The expression "place of work" is defined in s 4 of the Act to mean "premises or any other place, where persons work." 94 The fireworks display on 28 February 1997 was conducted at Newcastle Showground by Mr Howard and an employee of the defendant, Mr Lawrie. Mr Howard and Mr Lawrie were engaged in work in setting up and conducting the fireworks display and the place that they were working was Newcastle Showground. The fourth element of the offence is made out. 95 I find that each of the elements of the offence have been established. 96 I turn to consider whether a defence has been made out under s 53 of the Act. Section 53 provides as follows: "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. " 97 To establish a defence under s 53 the defendant must prove that, on the balance of probabilities, 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: Drake at 457; Sydney City Council v Coulson (1987) 21 IR 477 at 480; Italo Australian Construction Pty Ltd v Parkes (1988) 24 IR 428 at 431; WorkCover Authority of NSW (Insp Glass) v Kellogg (Aust) Pty Ltd at 15 2000 NSW IRComm 53. 98 If the offence charged had been limited to the south-western spectators which included Ms Westphal, I consider that the risk of an unexploded shell hitting a spectator would not have been readily foreseeable. I have already explained where Ms Westphal was situated in relation to the firing point and the direction of fire of the shells. The evidence was that the most likely probable cause of the deviation of the shell that hit Ms Westphal was a collision in flight with another shell. The prospect of collision was, on its own, readily foreseeable on the evidence but the combination of collision, together with the extremely low probability that the shell would fail to explode and that the unexploded shell would deviate at such an angle and travel such a distance was not readily foreseeable by the defendant. Not being readily foreseeable, it was not reasonably practicable within the meaning of s 53(a) of the Act for the defendant to prevent or guard against the risk to health or safety. 99 In relation to the north-eastern spectators, however, the risk to their health or safety was readily foreseeable. The mortar was pointing in the direction of this group of spectators; the spectators were inside the safety distance of 100 metres set by DG 108; the defendant was required to comply with DG 108 as a condition of its Permit to conduct fireworks displays; the defendant knew that shells could fail to burst; the defendant knew that unexploded shells could deviate from their predicted flight path; the defendant did not know how far the 100mm unexploded shell would travel at a mortar angled at five degrees from the vertical. 100 It is not a question of whether an employer did envisage a particular risk to health or safety but rather whether it should have: Kellogg at 15. In relation to the north-eastern spectators the defendant should have foreseen the risk to health or safety. The defendant, therefore, has not made out a defence under s 53(a) in relation to the offence. 101 Section 53(b) requires the defendant to prove to the civil standard that 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. I consider that on the evidence it would have been open to me to find that if the offence charged had been limited to Ms Westphal and the group of spectators on her side of the arena, the defendant could have made out a defence under s 53(b) for reasons similar to that which I have expressed relating to s 53(a). As Dr Green said in his evidence in Exhibit 2 at p49: "In my opinion this accident was unfortunate but outside the control of Mr Howard. A direct malfunction of the shell could not have been assessed prior to the accident. The fuse and shell is completely covered in paper and will look normal. The manufacturer has a high reliability for their products." "The angle and distance of the victim from the firing point relative to the wind direction are not consistent with the normal variations caused and expected from a simple misfire and impact of a blind shell. They are consistent, however, with a collision or deviation caused by a shell burst and subsequent failure of the fuse. The circumstances and likelihood of this type of collision are impossible to predict and are thus outside the control of Mr Howard." 102 However, given the scope of the offence charged, which I have found includes spectators in the direction of flight of the aerial shell, I consider that, in relation to the offence charged, no defence is made out under s 53(b) of the Act. 103 Given what I have said about the s 53(a) defence in relation to the north-eastern spectators it is obvious why I do not accept that a defence has been made out under s 53(b) of the Act. Clearly, the risks to health or safety were due to causes over which the defendant did have control and against the happening of which it was practicable for the defendant to make provision. 104 I find the offence proven. 105 Leave is granted to the parties to seek to have this matter re-listed in order that the question of penalty might be addressed. Annexure One 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.