Leslie Corbett v South 32 Limited

B. Issues

1. The statutory principles governing an order for contribution are found in s 5 of the Law Reform (Miscellaneous Provisions) Act 1946, which relevantly provides: "5 Proceedings against and contribution between joint and several tort-feasors (1) Where damage is suffered by any person as a result of a tort (whether a crime or not): (a) judgment recovered against any tort-feasor liable in respect of that damage shall not be a bar to an action against any other person who would, if sued, have been liable as a joint tort-feasor in respect of the same damage, … (c) any tort-feasor liable in respect of that damage may recover contribution from any other tort-feasor who is, or would if sued have been, liable in respect of the same damage, whether as a joint tort-feasor or otherwise, so, however, that no person shall be entitled to recover contribution under this section from any person entitled to be indemnified by that person in respect of the liability in respect of which the contribution is sought. (2) In any proceedings for contribution under this section the amount of the contribution recoverable from any person shall be such as may be found by the court to be just and equitable having regard to the extent of that person's responsibility for the damage; and the court shall have power to exempt any person from liability to make contribution, or to direct that the contribution to be recovered from any person shall amount to a complete indemnity."
2. The appropriate amount of contribution is that which is "just and equitable having regard to the extent of that person's responsibility for the damage". [2] This "involves a comparison both of culpability, i.e. of the degree of departure from the standard of care of the reasonable man…and of the relative importance of the acts of the parties in causing the damage". [3]
3. In addition, contribution can only be recovered from Allfab if it is a "tort-feasor who is, or would if sued have been, liable in respect of the same damage". [4]
4. Accordingly, the issues in the proceedings are: 1. Whether the steps or "precautions" asserted by West Cliff - such as opening the dump valve, peering through the inspection hole and contacting the control room - satisfy the necessary requirements of ss 5B and 5C of the Civil Liability Act 2002 ("CLA") so that negligence is not excluded and Allfab "would…have been liable" to Mr Corbett. 2. Was the asserted breach - the failure to take the precautions - a necessary condition of the harm to Mr Corbett as required by s 5D of the CLA. 3. How did Allfab's degree of departure from the reasonable standard of care compare with that of West Cliff's; and what was the causal potency of Allfab's negligence, compared to West Cliff's, in contributing to Mr Corbett's damages. 4. What, if any, level of contribution should be ordered.
5. These matters are informed by and must be considered in the context of the events that led to Mr Corbett's injuries.

C. Factual background

1. The Washery contained a number of large conical-shaped tanks about 5 metres high [5] with the narrow end of the cone pointing towards the ground. These tanks were used to separate coal from refuse. [6] The separation process involved the tank being filled with a mixture of magnetite (a valuable material that was reused repeatedly in the process) [7] and water. At an appropriate strength of solution, coal would float and the refuse would settle. Periodically the tanks would need to be emptied so as to permit inspections and maintenance. One of these tanks was TK3-20C.
2. Allfab and West Cliff in 2011 entered an umbrella contract that regulated the provision of services between them under particular orders. [8] Time was of the essence in the performance by Allfab of its obligations. [9] Allfab personnel were to perform their tasks in a safe manner and not prejudice the safe working practices, safety and care of property, and continuity of work at the Washery, [10] and not interfere with West Cliff's activities at the Washery. [11]
3. Allfab were retained to inspect tanks at the Washery on the day of the incident, including Tank 3-20C.
4. Mr Corbett was a confined‑space watcher, [12] and worked for a company known as Turbo-Vac Australia Pty Ltd. Turbo-Vac was engaged [13] by West Cliff to provide a confined space watcher at the Washery. Mr Corbett provided this service for West Cliff. His role was to ensure, once a tank hatch was opened, that the air quality inside the tank would allow Allfab employees to enter and inspect the tank safely. Mr Corbett utilised specialised equipment to assess the gases in the tank.
5. Mr Corbett was directed by West Cliff as to the tanks to which he should go to undertake his confined space checks. He did not supervise Allfab employees, and they did not supervise him.
6. West Cliff had a detailed procedure designed to ensure that the hatch to a tank was opened only when the tank contained no "stored energy". Relevantly, this was when the tank was empty, for a tankful of magnetite solution contained significant gravitational potential energy. The procedure governing the removal of stored energy, and thus "isolating" a piece of equipment, was contained in West Cliff's "Isolation Standard". [14] This standard identified the roles of various employees regarding isolation procedures and training. It identified that the Engineering Manager was responsible to "[m]aintain the integrity and adherence to the … Isolation Standard", and that the "Isolation Supervisor" was responsible for "the activation and use of a Lockbox and Manual Remote Isolation" and had authority to "Isolate and de-isolate equipment". [15]
7. The isolation process involved, first, identifying energy sources [16] (such as the existence of magnetite solution in the tank), second, to advise relevant parties, third, "[t]o isolate and secure all energy sources before physical work starts", [17] fourth, "[t]o secure all energy source isolation points before work starts", [18] and fifth, "[t]o verify that all energy sources have been effectively isolated before work starts". [19] Steps 3 and 5, relevantly, appear to involve emptying the relevant tank and confirming that it is empty. Other than the use of an activated lockbox, explained below, there was no evidence that any of these steps were undertaken by West Cliff in respect of Tank 3-20C.
8. West Cliff conceded, as the consent judgment with Mr Corbett indicates, that it was negligent in its actions in breach of its duty of care to Mr Corbett. It did not call evidence to minimise or explain that negligence, or clarify how the tank came to be full of a magnetite solution and yet be listed in the Lockbox as having been isolated.
9. The evidence indicated that the inspection of Tank 3-20C by Allfab was, according to the Isolation Standard and the retainer of Allfab, supposed to be preceded by a number of preliminary steps, including as follows: 1. West Cliff would identify that Tank 3-20C required isolation so as to be inspected, and would advise relevant West Cliff personnel. 2. West Cliff would then isolate Tank 3-20C. That tank would be listed on the Group Isolation Board in the list of tanks to be inspected by Allfab. (In this case, Tank 3-20C was so listed, but it was apparently not emptied of its contents. It contained stored energy in the form of magnetite slurry [20] and was thus not properly isolated at the time the hatch was opened.) 3. The West Cliff Isolation Supervisor would ensure that the tank was emptied, or isolated, and would then attach his blue lock [21] and isolation permit to the Group Isolation Board. This signified that the tank was isolated, that it contained no stored energy, and that it was thus safe to inspect. [22] (In this case, the blue lock and an isolation permit tag were placed on or attached to the Group Isolation Board, [23] but apparently the Isolation Supervisor had not, nor had anyone else, confirmed that the tank was empty.) 4. Allfab would receive instructions to inspect the tank. (In this case, the West Cliff "Permit to Work" confirmed in a document signed by Josh Woodford, [24] perhaps the Isolation Supervisor, that "all Energy Sources" were "identified & isolated". The Allfab supervisor signed to confirm that he understood and accepted this confirmation. Mr Woodford and Phil Howes, [25] the "process engineer", also signed off on the isolation permit [26] for Tank 3-20C.) 5. Allfab employees would place their red locks on the Group Isolation Board, signifying that they were working on the tank. The tank would then remain "isolated" until all the locks were removed. (In this case, the Allfab employees did place their red locks on the Group Isolation Board. [27] ) 6. Allfab would loosen and open the hatch to the tank. 7. Mr Corbett would check the confined space in the tank for safety. 8. Allfab would proceed to inspect the tank.
10. The tank hatch was a circular door about 1 metre in diameter located near the foot of the tank. It was attached to the tank by two large hinges on one side and by 20 evenly spaced bolts around its circumference.
11. Late in the afternoon of 2 June 2015, Mr Corbett was directed by West Cliff to attend tank TK3-20C. Allfab employees also gathered at that tank. Mark Chappell of Allfab commenced to remove the bolts on the hatch towards the bottom of the tank. Mr Chappell, with others, signed a document which gave his account of the procedure as follows: "The task was tank inspections. Remove inspection cover and then inspect inside. At the time the incident occurred we had removed all the bottom bolts from the hatch. We left one bolt with tension at about 9 o'clock, approximately opposite the hinge. The other remaining bolts were loose. There were approximately 9 bolts still in the hatch that were loose. These remaining bolts that were loose had a couple of threads engagement. We then started to loosen off the last bolt that had tension. The door opened about 10-12 mm as we were undoing the thread. We could see that there was no indication of any product coming out. I then proceeded to take the loose bolts out by hand. After the loose bolts were removed I then used the rattle given to commence removing the final bolt. As I was removing the last bolt with the rattle given the door opened and initially a little bit of product slumped out and then it suddenly all came out. Before I commenced removing the last bolt I said to the crew I am about to remove the last bolt just move back out of the way. This was the 4th sump inspection for the day. The first sump was inspected today (4-30C) we loosened the bottom bolt of the hatch and cracked the sump bolts then produce started to leak out We followed the same procedure for the second sump (4-11) and no product came out and so we continued with the inspection without incident. We followed the same procedure for the 3rd sump inspection (3-1A). We would see that water was flowing through the sump because there was a valve open. I wanted to know where the water was coming from so I cracked a gate valve (6" or 8"). When we cracked the valve we stood out of the line of fire and a small amount of water ran out. We cracked it further and no additional material came out. There were some other knife and I checked to see what position they were in. We could now see that there was no more water and proceeded to remove the hatch. While we were undoing this hatch no material was coming out. We proceeded to completely remove the hatch. It was very tight to open - we had to use a bar to fully open it. At the start of the day we read our job pack and put our locks on the board specified by the job pack. At the start of the day the workpacks were handed out by our supervisor Chris. Stored energy was identified as a hazard on our JSA. The cracking procedure was our control for checking for stored energy. " [28] [Errors in original].
12. Allfab objected to the use of the signed document. It was created shortly after the incident, before Mr Chappell had received any legal advice and whilst the stress of the preceding incident may have been impacting upon his thoughts and emotions. But in the course of his evidence, Mr Chappell accepted the correctness of the written document, and I accept it as evidence of what occurred.
13. Neither the evidence nor either party suggested that any of the tanks whose hatches had earlier been opened that day (before TK3-20C) contained any significant quantity of magnetite slurry. Some of this magnetite solution or sludge may have been on the hatch opening or inside the hatch of those tanks, and came out as the hatch was opened, such as in the cases of the first and third tanks opened that day. West Cliff's confined space entry procedure [29] appeared to assume that tanks were empty before inspection.
14. Mr Corbett gave some evidence that the hatch on Tank 3-20C was opened with a scaffolding pole. [30] This was forcefully rejected by Mr Chappell. [31] The contemporaneous statement [32] quoted above shows that a pole or "bar" was used earlier in the day to open the hatch of another tank and is not referred to in the account of opening Tank 3-20C. I prefer Mr Chappell's account, supported by the contemporaneous statement, and perhaps by another contemporaneous note referring to a "single bolt in the inspection hatch base", [33] although this evidence was not canvassed in submissions. West Cliff, in submissions, seemed not to support Mr Corbett's account. [34] I do not accept that a pole was used on the occasion of opening Tank 3-20C.
15. I also accept that Mr Corbett was told to move back out of the way before the last bolt on TK 3-20C was removed, although he could not recall it, [35] because the instruction was recorded on the contemporaneous signed statement [36] and Mr Chappell gave evidence of it. [37] I also accept Mr Chappell's evidence that Mr Corbett moved as a result of the instruction. [38]
16. Mr Corbett was injured when a large quantity, perhaps a tankful, [39] of the magnetite slurry poured out through the hatch of Tank 3-20C.

D. Oral evidence

1. Timothy Pratt, the Manager of Mechanical Engineering at the West Cliff Washery, [40] gave evidence that the safety protocol of West Cliff required isolation points to be tagged, [41] that the Isolation Supervisor uses blue locks [42] to signify that an isolation point has been isolated and thus is safe to work on, [43] and "absolutely" that the person, presumably the Isolation Supervisor, needs to have satisfied themselves that the equipment listed on the Group Isolation Board has been effectively isolated (presumably, before affixing his blue lock). [44]
2. Mr Pratt also confirmed that Allfab were not expected "to manipulate the isolation points themselves", [45] nor were they trained to find isolation points. [46] Isolation points are apparently those points at which isolation can be effected (e.g. perhaps the dump valve) or confirmed (e.g. perhaps the inspection hole, the control room, or, uncontroversially, the Group Isolation Board). He said: "[I]f the equipment is listed on the board and is locked up behind the blue lock, and it's listed in the list of isolated equipment, then placing a lock on that isolation board would be what is required to work on that equipment." [47]
3. According to Mr Pratt, checking the dump valve or contacting the control room was not a procedure directed by West Cliff's confined space entry procedure, [48] and checking the inspection hole was not a matter listed on the isolation permit. [49]
4. Mark Chappell, an employee of Allfab, gave evidence. He did not suspect "at all" that the tank might be full. [50] Since his job pack and work order corresponded with the Group Isolation Board, he believed that the tank was isolated and safe to work on. [51] Mr Chappell was not challenged on his evidence that it was not his usual practice to go to the top of a tank to inspect it, [52] nor to operate a dump valve, [53] nor had he ever been directed to do so. [54] He knew nothing of a level transmitter and was not told anything of it. [55] He did not know there was an inspection hole. [56] He knew nothing of the isolation points (other than the Isolation Board) and was not told anything of them. [57]
5. Mr Chappell put his red lock on the Isolation Board [58] and adopted his usual procedure to remove the bolts. As he came to the last couple of bolts, he instructed the crew to move out of the way [59] so that they were not in the "line of fire" in respect of any residual material sitting on the hatch. This method of loosening the bolts was not to check whether the tank was full or not, [60] but Mr Chappell conceded in cross-examination that the technique of loosening the bolts was his "control over the stored energy issue". [61] In re-examination, he confined his reference to "stored energy" to the residual material on the hatch. [62]
6. Mr Chappell conceded that he did identify a risk that people possibly could get hurt if they were in the line of fire [63] and that although Mr Corbett was told to move out of the way, he did not move far enough, and got hurt because he remained in the line of fire. [64]
7. The following exchange occurred: "Q. You went on with the task despite recognising that very risk may hurt him, didn't you? Will you answer that question? A. Yes. Q. Is the answer 'yes'? A. Yes." [65]
8. Consistent with Mr Chappell's earlier evidence, [66] West Cliff eschewed the submission that this answer was evidence that Mr Chappell recognised the possibility of the tank being full of magnetite slurry rather than there being some residual magnetite sludge on the hatch, [67] although West Cliff did not accept that any such distinction was relevant. [68]
9. Mr Chappell gave evidence [69] that an Allfab colleague, Rick Reitzer, confirmed with the Isolation Coordinator that there was no stored energy in the system. Mr Chappell's evidence of this representation by Mr Reitzer is not evidence of the absence of stored energy (which was, in any event, disproved by the other evidence), nor is it evidence of what the Isolation Coordinator said since Mr Reitzer was not called as a witness, [70] although it is evidence of what Mr Chappell was told and believed, a matter not disputed. Although West Cliff bore the onus of proving negligence by Allfab, it did not call evidence as to what its Isolation Coordinator did or did not do or say.
10. Mr Chappell's evidence of what he did to "positively isolate stored energy" is that "All it was, was my red lock being put onto the isolation board". [71] He said, "My belief is by having my Jobpac and my work order and it corresponds to the group isolation board, that that tank has been isolated and it is safe to work on". [72]

E. Breach of duty: failure to take precautions

1. Allfab did not dispute that it owed a duty of care to Mr Corbett. But it asserted that it neither knew nor ought to have known of the risk of the harm that befell Mr Corbett, namely, the uncontrolled discharge of stored energy in the form of a tankful of magnetite slurry rushing out of the tank through the hatch.
2. What Allfab knew or ought to have known is highly relevant to the nature of the duty of care. Section 5B(1) of the CLA precludes negligence unless Allfab knew or ought to have known of the risk of harm, harm being defined as "harm of any kind" in s 5 of the CLA.
3. Mr Chappell knew or ought to have known that one purpose of the tank is to contain a large amount of liquid material. If there remained in the tank a large amount of material, it would inevitably pour out when the hatch was opened. But Mr Chappell did not believe that there was a significant quantity of material in the tank because of the isolation procedure: "Look, they did their own isolations" he said. [73] That procedure, performed correctly, would ensure the absence of material in the tank. Mr Chappell believed that another person, in this case presumably the Isolation Coordinator, had checked that the tank was empty and had confirmed that by placing a blue lock on the Isolation Board which listed Tank 320-C as having been isolated. [74]
4. The circumstance that someone else is supposed to have both emptied the tank of material and checked for the absence of material in the tank is not foolproof. To assume otherwise denies the existence of human error. It was foreseeable that human error could have occurred, that the check of the tank's contents had been overlooked or defectively performed. Thus the risk of harm might be foreseeable at common law. As Dixon CJ observed in argument in Chapman v Hearse, [75] "I cannot understand why any event which does happen is not foreseeable by a person of sufficient imagination and intelligence." Perhaps that test excluded only the "far-fetched" and "fanciful", [76] and did not embrace any notion of probability or likelihood.
5. But a "foreseeable" risk is defined differently in s 5B(1)(a) of the CLA. It means "a risk of which the person knew or ought to have known".
6. A failure to take precautions against a risk of harm is not negligence unless the requirements in s 5B of the CLA are satisfied. West Cliff alleges that Mr Chappell negligently failed to view through the inspection hole, to open the dump valve, to check with the control room, and to refuse to continue work. Section 5B provides that a failure to take these precautions cannot be negligence unless Mr Chappell (not having known) [77] ought to have known of the risk of a full tank. It must also be the case, in order to establish negligence, that the risk of a full tank was not insignificant, and that a reasonable person would have taken some or all of the precautions identified. In undertaking a consideration of what precautions a reasonable person would take, [78] the Court is required to consider, at least, the probability and likely seriousness of harm, the burden of avoiding harm (and all similar risks of harm - see s 5C(a)) and the social utility of the inspection of the Washery tanks.

Probability

1. The probability of harm is both an express necessary consideration in determining the conduct of a reasonable person, [79] and a determinant of whether negligence is excluded. [80] Assessing probability is difficult in the absence of evidence. As there is no evidence that the hatch was ever previously opened when the tank (or any tank) was full, or that the isolation procedure ever failed to identify and protect against a full tank, matters within the knowledge of West Cliff, I would infer that this was the first occasion when a hatch was opened on a full tank. There is no evidence to disprove that the risk of the hatch door being opened on a full tank (when the tank is listed on the Isolation Board under a blue lock), and thus the risk of harm from a full tank, was small, even insignificant, or that the probability was very low.
2. It is also difficult to assess what part of the isolation procedure failed. It would seem most unlikely that West Cliff, as part of the isolation procedure, did not identify a full tank as an energy source (the first step), [81] but plainly the second and fourth steps - isolating energy sources and verifying that all energy sources are isolated - did not occur here. The circumstance that the roles of persons in the isolation procedure were clearly defined, and that there was a backup check (in step 4) of the isolation step (in step 2) also suggests that the probability of a hatch being opened on a full tank was very low.
3. But the risk of harm under s 5B of the CLA could embrace any harm, [82] not just harm resulting from a full tank being opened. Perhaps there was a risk that Mr Corbett could be harmed by some sludge residue on the hatch, or from contact with the swinging hatch on opening. There is evidence of a small amount of material coming from two earlier tanks when the hatch was opened. [83] But there is no evidence of harm on those occasions, or potential harm. The risk of harm from those possibilities seems to be excluded by the method of removing the bolts, and by Mr Corbett being directed away from the hatch just before it was opened. He remained in the "line of fire" of a full tank, but I was not satisfied that he remained in the line of fire, at potential risk, from residual sludge on the hatch or collision with the hatch on opening. I do not regard the somewhat ambiguous exchange quoted at [34] above as inconsistent with this finding, nor with a finding, which I make, that Mr Chappell did not recognise any risk of any harm to Mr Corbett when he opened the hatch after having told "the crew…[to] just move back out of the way". [84] Mr Corbett moved to the hinge side, away from the opening, on that instruction. [85]

Other elements/considerations

1. Whatever be the objective probability of the harm, or the objective insignificance of the risk, a relevant matter in assessing how that probability or insignificance might operate on Mr Chappell depends on what he knew or should have known of the risks and probabilities. [86] If (unknown to Mr Chappell) West Cliff had a defective adherence to the isolation procedure (an inference that might be available given the absence of evidence on the matter), it is difficult to see how, without other evidence, that would increase what Mr Chappell ought to know, or increase the precautions taken by a reasonable person in his position. He knew that the tank was listed on the Isolation Board, and that the blue lock and isolation permit tag were present, so all indications so far as he then knew were that the isolation procedure had been followed.
2. What Mr Chappell ought to have known might be otherwise expressed as constructive knowledge, what the reasonable person in his position would have known. The considerations have been stated thus: "The establishment, by a plaintiff, of constructive knowledge in the defendant of the risk of harm necessarily depends upon all of the facts, matters and circumstances which were known to it or else ought to have been known to it. In addition to the particular facts and circumstances of this case, other matters which may impact upon the drawing of an inference as to knowledge may include such things as the common knowledge and experience of others in similar positions to the defendants, public notoriety of a particular risk of harm, publications containing academic exposition of risk which might be expected to be read by people in the position of the defendant, and as well, the obviousness or likelihood of an event happening when applying common sense. It is important to emphasise however that knowledge, whether actual or constructive, must be judged as at the date of the alleged negligence and not at a later date; that is, without the benefit of hindsight and ignoring subsequent increases in knowledge about the risk and its consequences." [87]
3. Thus, paragraphs 5B(1)(a) and (c) of the CLA, in their application to Mr Chappell as a person who did not know of the risk, involves what the reasonable person in his position would have known, and would have done. As to knowledge, no submission was made as to why Mr Chappell's knowledge of the risk was unreasonable, or that he failed to recognise something that others would reasonably have recognised. So far as the evidence reveals, no one at Tank 3-20C recognised the risk, nor anyone at West Cliff. None of the matters listed in the above quoted passage from Garzo indicate that the reasonable person would have known, or acted, differently from Mr Chappell.
4. Mr Chappell did not know or suspect that Tank 3-20C was or could be full of magnetite slurry. As mentioned above, [88] West Cliff did not submit that Mr Chappell recognised that possibility. How then could it be said that Mr Chappell nevertheless "ought to have known of the risk"?
5. West Cliff contended that the "risk" was a risk of harm from magnetite slurry in the tank, and that no distinction should be drawn between a risk of eye damage from a small piece of magnetite sludge on the hatch, and the risk of damage from a large quantity of magnetite slurry pouring from the hatch and striking Mr Corbett. But identifying the risk is necessary to assess the reasonable response to that risk, [89] for the terms of s 5B(1)(a) link the precautions against a risk to the particular risk which "ought to have [been] known", whether the risk is injury from a swinging hatch, injury from a piece of magnetite sludge, or injury from a tankful of magnetite sludge.
6. Mr Chappell's statement records that his "cracking procedure", that is, loosening the bolts on the hatch so as to break the seal between the tank and the hatch door, prior to removing the bolts, was his "control for checking for stored energy". [90] This statement recognises both the possible existence of stored energy, and that it was significant enough as a risk to warrant a special procedure of loosening the bolts to ensure that any stored energy was guarded against. While with hindsight this stored energy could be in the operation of the hatch opening, in magnetite sludge on or near the edge of the hatch, or in a full tank, but to Mr Chappell, in the circumstances, the final of these three possibilities was not suspected.
7. Evidently the cracking procedure proved to be insufficient against the risk of harm from a full tank of magnetite solution. The contents of the tank were not manifest even after the seal was cracked, until the bolts (or all but one) were removed, presumably because of the viscosity of the magnetite slurry. The cracking procedure indicated, inaccurately, that the tank was not full of magnetite slurry because no significant quantity poured out when the bolts were loosened and the seal was "cracked". But, on Mr Chappell's evidence, the bolt loosening procedure was a precaution against a small amount of magnetite on the hatch, not a tankful, and West Cliff did not submit otherwise. In that case, the insufficiency of the cracking procedure to prevent injury from a tankful of magnetite slurry is not to the point.
8. West Cliff did not assert that the cracking procedure was performed negligently, or that it was counterproductive, only that it was insufficient.
9. Moreover, Allfab did take steps to ensure that there was no substantial stored energy, in this case a large quantity of magnetite solution, in the tank: Allfab followed the isolation procedure adopted by West Cliff in the Isolation Standard. The procedure required "[e]ach individual who is applying their Personal Isolation Lock to an active Lockbox" to: 1. "ensure that all of the equipment requiring isolation for their work is listed on the Isolation Permit Tag"; 2. "ensure that the Lockbox is active by observing the Isolation Supervisors lock and Isolation Permit Tag is on the Lockbox lid clasp"; 3. view that the "Isolation Permit Tag details are complete"; and 4. view that "the Isolation Supervisor and Verifying Person(s) signature(s) are on the Isolation Permit to confirm the isolation has taken place and that the test for dead has been performed". [91]
10. The Allfab employees followed this procedure then placed their locks on the board. Until all locks were removed from the board, the isolation procedure mandated that the tank was not to be operated but was to remain isolated. West Cliff did not suggest any failure by Allfab in this regard.
11. The matters which West Cliff alleged Allfab were required and failed to do require specific attention. However, if a reasonable person in Mr Chappell's position would not have known of the risk of a full tank, then s 5B(1)(a) of the CLA is not satisfied in any event.

(a) Dump valve

1. The dump valve is connected to a pipe leading from near the bottom of the tank to about a metre away, opening towards the floor. It is located on a level just lower than the bottom of the hatch. It has a valve capable of being opened and closed. When the valve is opened, material from the tank, depending on its consistency, may be able to escape or flow from the tank through the short pipe onto the floor below the tank.
2. The dump valve pipe appeared to be about 150 millimetres in diameter. Its size was not the subject of evidence, and this estimate is derived from photographs showing handrails and other items of recognisable or recorded dimensions near the location of the dump valve pipe and may be inaccurate. The diameter of the dump valve pipe appeared about to be one-seventh the diameter of the hatch, which itself appeared to have a diameter of approximately 1 metre. [92]
3. Opening of the dump valve was not evidenced to be part of any written procedure to isolate the tank and ensure that it contained no stored energy.
4. Mr Corbett had performed a confined space watcher role at the Washery for about two years before the incident. He understood that once the tank was on the Group Isolation Board list, any opening of valves should have already been done. [93]
5. Mr Pratt, the West Cliff engineer, gave evidence that the stored energy could be released by opening the dump valve. [94] But this is not evidence that Mr Chappell, acting reasonably, should open the dump valve, particularly in view of the other evidence of Mr Pratt discussed above. [95] The circumstance that: "a risk of harm could have been avoided by doing something in a different way does not of itself give rise to or affect liability for the way in which the thing was done". [96]
6. Whether the dump valve was customarily used by West Cliff to empty a tank's contents was not the subject of direct evidence. The isolation procedure in respect of stored energy in the tank did not refer to opening the dump valve. Mr Pratt stated that if the dump valve was to be an isolation point, it would have been fitted with "personal locking devices" [97] but none were fitted at the time of the incident. Thus, the dump valve did not appear at that time to be regarded by West Cliff as an isolation point. [98] West Cliff provided no instructions to Allfab about the use of the dump valve. Assuming that the dump valve was effective to drain the magnetite slurry, opening it would involve dumping a large quantity of potentially hazardous material in the area surrounding the tank, which was not part of Allfab's work order and which appears inconsistent with its obligations in the umbrella contract. Mr Pratt confirmed that Allfab employees were not expected to do this. [99]
7. I do not regard it as the conduct of a reasonable person in Mr Chappell's position to open the dump valve at the premises of Westcliff without instructions, without information as to its consequences, in a context where a different isolation procedure involving the Group Isolation Board locks was mandated and utilised, and in view of the contractual obligations on Allfab not to prejudice the safe working practices, the safety and care of property, and the continuity of work of West Cliff at the Washery. It is not a precaution that satisfies s 5B(1)(c) of the CLA.

(b) The inspection hole

1. The inspection hole was a circular aperture of about 250 millimetres in diameter at or near the top of the tank. "It's pretty much at just under chest height", [100] but was on another level from the hatch, about 5 metres above up some stairs. [101] There was no evidence that Allfab, or Mr Chappell, in particular, knew of the existence of the "inspection hole" or where it was located. Mr Chappell testified that he "didn't know there was an inspection hole". [102]
2. There was no evidence to indicate that Mr Chappell should have discerned the existence of an inspection hole, or where it would be found, or whether it would enable him accurately to conclude anything about the existence, nature and quantity of material in the tank, even if Mr Pratt, as the Washery engineer, might have been able to discern such matters from an observation into the inspection hole. I do not think a reasonable person in the position of Mr Chappell would embark on an uninstructed reconnaissance mission to see if and where an inspection hole might be located. There was no evidence that the inspection hole was the conventional, or other, means by which an Isolation Coordinator might confirm the absence of stored energy in the tank. The isolation procedure did not indicate that it was a test or step that needed to be performed by Allfab, a matter confirmed by Mr Pratt's evidence. [103]
3. Mr Corbett had never observed a worker check the contents of the tank by viewing the inspection hole. [104]
4. In these circumstances, I was not satisfied that a reasonable person in Mr Chappell's position would be aware of the inspection hole, or would utilise it to confirm the absence of material in the tank. It also is not a precaution that satisfies s 5B(1)(c) of the CLA.

(c) The control room

1. The third item raised by West Cliff was to contact the control room operator.
2. The tank had a device, a "level transmitter", which allowed the West Cliff control room to ascertain the level of the contents of a tank. Mr Pratt gave evidence of this level transmitter. He said "[P]eople wouldn't know what to look for in terms of that level transmitter". [105] Whether it was operational on the day of Mr Corbett's injury, what steps needed to be taken in the control room to ascertain the tank level, why they were not utilised by West Cliff on the day in question, why the device was apparently not used in the isolation procedure on this occasion, are all matters not the subject of evidence. Mr Corbett was not asked about the control room or the level transmitter, and, I would infer, did not know of the transmitter or the control room's knowledge of the tank level.
3. Again, I do not think it reasonable for Mr Chappell to contact the control room for information about the tank when he is not informed, and there is no reason for him to believe, that the control room has information about the level of material in the tank. Again, the isolation procedure did not indicate such a step should be taken. Again, it is not a precaution that satisfies s 5B(1)(c) of the CLA.

(d) Cease work

1. West Cliff also submitted that Allfab should have "ceased work". But this is contrary to Allfab's obligations to efficiently proceed with its obligations, and in a context where a specific and detailed procedure was undertaken by Allfab: checking the tanks listed, and using personal locks on the Group Isolation Board as mandated by the Isolation Standard.
2. There was nothing to indicate to Mr Chappell that the proper isolation procedures had not been undertaken by West Cliff, or to indicate to him that there was any stored energy in the tank. Mr Chappell had been informed that the Isolation Coordinator had confirmed that there was no stored energy in the tank, a matter confirmed by the Group Isolation Board. I have found that a reasonable person in Mr Chappell's position would not have done something substantial outside that procedure, whether to open a dump valve, search around the tank and the Washery for an inspection hole, or contact the control room. Nor would that reasonable person sit idly by until some greater confirmation of safety was received. One purpose of the Isolation Standard was to remove the need, and the option, for contractors to engage in any unplanned investigations about the contents of the tank.

(e) Other matters

1. West Cliff made particular reference to Allfab's Safe Work Method Statement [106] in respect of the Washery Tank Maintenance order. Job Step 3 of the Statement, which appears before Job Step 4 "Remove Hatch for entry", is titled "Check isolation requirements". The hazard identified is "Stored energy", and is rated 4 in the "Risk" rating numbered 1 to 5 in ascending order of risk. Under the column headed, "Hazard Control & Work Method", is recorded: "- Before starting work have the Isolating Coordinator confirm there is no stored energy in the system - Attach personal red locks to isolator/GIP before starting work - Positively isolate stored energy".
2. As to the first item, Mr Chappell gave evidence that a colleague, Rick Reitzer, informed him of having confirmed that there was no stored energy in the system. [107] In any event, West Cliff did not rely on this first item. Nor did it rely on the absence of any personal red locks contrary to the second listed requirement. Rather, the focus of West Cliff was on the third item, "Positively isolate stored energy".
3. The Safe Work Method Statement did not identify what was encompassed by the phrase "Positively isolate stored energy". No evidence suggested that it must be exclusive of the other items in the Work Method Statement. Even if it were, it could refer to ensuring that the task is listed on the Isolation Board and that the isolation permit tag and blue lock are in place, matters which were apparently done by Mr Chappell. Or it could refer to circumstances where there was some other indication of stored energy (either in the contents of the tank or in some other form). It evidently does not expressly require any of the three items propounded by West Cliff, namely, opening the dump valve, peering down the inspection hole, or contacting the control room. The only one of those methods that strictly could perhaps "[p]ositively isolate stored energy" (the others being methods to confirm that isolation has occurred) would be to open the dump valve, and, for the reasons given, I do not regard that as an isolation requirement that was appropriate for Allfab to undertake. It may be that if the confirmation with the Isolation Coordinator identified some further step for Allfab to take, that step was to be covered by the third item. Or it may embrace the "cracking the seal" procedure in relation to material on the hatch, the step undertaken immediately before or as part of removing the hatch. To the extent that it was a further reminder to ensure that there was no stored energy in the tank, that step was fulfilled by checking the details on the Group Isolation Board to ensure that Tank 320-C was identified and the isolation permit and blue Isolation Coordinator's lock was in place. That, together with cracking the seal, were the methods by which Allfab could confirm that stored energy had been "[p]ositively isolate[d]".
4. West Cliff submitted that Allfab should "do something so as to positively isolate stored energy in the tank". [108] I do not think that takes the matter further. If there was a precaution that should have been undertaken, it needs to be identified. No step has been identified other than those considered above. I do not accept that Allfab's negligence could be established by a failure to take a precaution, if the content of that precaution cannot be identified.
5. Section 5B(2) of the CLA also requires that I consider the burden of precautions, and the social utility of the activity. The other precautions suggested by West Cliff imposed no particular burden. To open a dump valve or to view down an inspection hole were easy enough to do if they were known. The real question is whether Allfab should be burdened with additional enquiries about the desirability or utility of opening the dump valve or the availability of an inspection hole. That was a necessary preliminary to the steps alleged. Other additional precautions or enquiries can be imagined. Even though these burdens do not appear especially onerous, I was not persuaded that it was incumbent upon Allfab to go outside the mandated, established isolation requirements, potentially creating other risks foreseen and unforeseen, without instructions to do so.
6. Neither party raised any point about the social utility of inspecting the tanks.
7. In the result, I am not satisfied that a reasonable person in Allfab's position would have acted differently and taken additional precautions to those taken by Allfab or that Mr Chappell ought to have known of any risk that required those precautions to be taken. It follows that Allfab has not been negligent.
8. These findings are sufficient to dispose of the proceedings. However, I propose to make some further brief comments about the issues of causation and contribution.

(f) Causation

1. Allfab is only liable for contribution if it is liable in respect of the damage to Mr Corbett caused and admitted by West Cliff, even if causation is not part of the defined term "negligence". [109] Causation requires proof of factual causation and scope of liability as provided in s 5D of the CLA. No argument was presented in respect of "scope of liability" and if the necessary items in s 5B were established, there is no reason why Allfab's liability should not extend to the harm caused to Mr Corbett.
2. The question of factual causation, that "negligence was a necessary condition of the occurrence of harm", otherwise known as the "but for test" [110] raises the question of whether opening the dump valve, viewing down the inspection hole, or contacting the control room, would have revealed that Tank 3-20C was full of magnetite solution so that the hatch would not have been opened.
3. Mr Pratt described froth appearing on the top of the magnetite slurry because the mixture is constantly being agitated [111] and that this froth should be able to be seen. [112] So if the tank was empty [113] or in operation, the level of material in the tank appears to have been visible through the inspection hole. The evidence did not extend to whether this froth existed when the tank was not in operation, or, if not, whether the level of material in the tank was then visible.
4. I was not satisfied that viewing down the inspection hole would have revealed the material in the tank. The view through the inspection hole is indicated by darkness in one photograph that does not reveal the existence or otherwise of material in the tank. Mr Pratt's evidence of visible froth when the tank is operating, did not establish what is visible if the tank contained a substantial quantity of magnetite solution in circumstances when the tank is not operating, less still in the late afternoon on a winter's day within three weeks of the winter solstice. [114] I was not satisfied that anything other than blackness would be seen in those circumstances.
5. There was no evidence that contact with the control room would have informed anyone of the true level of contents of the tank.
6. As to the dump valve, there was no evidence of what would be produced by its opening on this occasion.
7. The cracking procedure, seemingly producing a small aperture, [115] was ineffective to establish the existence of a full tank of magnetite solution. But the dump valve, when opened, would seem to have had a larger aperture than the cracked seal. Notwithstanding the lack of evidence about the viscosity of the magnetite slurry, [116] and what use had been made of that dump valve to empty TK 3-20C of solution, I think it likely that an open dump valve would have revealed the existence of the full tank and may also have removed the risk by emptying the tank.
8. Accordingly, I find that if it was negligent of Allfab to fail to open the dump valve, that failure was a necessary condition of the harm to Mr Corbett. If Allfab had a duty to so act, liability would also be within the appropriate scope of liability under s 5D of the CLA. I am not satisfied that a failure to view the inspection hole or contact the control room would have revealed the contents of the tank, and so those failures would not be a necessary condition of the harm. Self-evidently stopping work and not opening the hatch would have prevented the harm so long as it was maintained, but there was no evidence to indicate what would or might be the instruction from West Cliff in that circumstance.

F. Contribution

1. By mandating a detailed Isolation Standard to be followed by all persons, West Cliff assumed responsibility to ensure that the tank was empty. It did not do so.
2. No evidence was called from the Isolation Coordinator, but it appears that Tank 3-20C was never checked. The documentary and oral evidence indicates that there was a belated decision by West Cliff to keep Tank 3-20C operating and not close it down for inspection. [117] However, by this stage, apparently the list of tanks for inspection, including for the purpose of the work order and the information on the Group Isolation Board, had been prepared. This does not explain why the Isolation Coordinator did not isolate the tank listed on the Isolation Board before attaching the blue lock, or if that was done, why West Cliff ignored its own isolation protocol in using the tank whilst it was listed on the Group Isolation Board.
3. This was a fundamental safety procedure that was apparently ignored. There was no evidence to explain it. I regard it as a gross breach of duty because it rendered useless the entire isolation protocol. A Jones v Dunkel inference is available because of the failure by West Cliff to call, or explain the absence of evidence from, the Isolation Coordinator, or someone else who could explain the isolation failure. I would draw the inference that the evidence from the Isolation Coordinator or others could not have assisted West Cliff. In any event, there was no evidence to mitigate the apparent gravity of the negligence.
4. Nor were any West Cliff witnesses called to indicate any safety procedure involving the use by contractors (or even by West Cliff employees when implementing the isolation protocol) of the dump valve, the inspection hole or the control room. The evidence of Mr Chappell, [118] Mr Pratt [119] and Mr Corbett [120] points to an inference that these were not steps undertaken by third parties and employees.
5. If, contrary to my findings, the failure by Allfab to take these further steps and, in particular, to open the dump valve without instructions, was negligent, it seems to me to be of a wholly different level of magnitude to the negligence of West Cliff.
6. The same is true of causal potency. The risk was directly created by West Cliff, which may have been avoided by Allfab's subsequent use of the dump valve. I regard the creation of the risk by West Cliff of greater causal significance than any omission of Allfab in failing to avert that danger. Damage was a real and reasonable possibility, if not inevitability, from the failures of West Cliff to follow the Isolation Standard unless the problem was discovered by the cracking procedure. On the other hand, the failures of Allfab had, so far as the evidence revealed, never been undertaken previously and no damage had resulted.
7. By its claims, West Cliff seeks to make Allfab responsible for failing to cure West Cliff's defaults. Even if Allfab had such a duty to Mr Corbett in this case, contrary to my findings, the causal potency and degree of culpability of West Cliff's actions are by far the greater.
8. For these reasons, I would regard the appropriate level of contribution under s 5 of the Law Reform (Miscellaneous Provisions) Act 1946 as 15% if negligence by Allfab was otherwise found.
9. Costs should follow the event: West Cliff should pay the costs of Allfab arising out of the cross-claims.

G. Orders

1. The orders of the Court are: 1. Cross-claims dismissed. 2. The first, second and fourth cross-claimants to pay Allfab Constructions Pty Limited's costs of the cross-claims.

Endnotes

1. T69/46-48.
2. S 5(2), Law Reform (Miscellaneous Provisions) Act 1946.
3. Podrebersek v Australian Iron & Steel Pty Ltd [1985] HCA 34 at [10], see also Grima v RFI (Aust) Pty Ltd [2014] NSWCA 345 at [41].
4. S 5(1)(c), Law Reform (Miscellaneous Provisions) Act 1946.
5. See Exhibit 3, pp 88, 107.
6. T40/26-32.
7. T42/1-13.
8. Exhibit 3, Tab 3, pp 6-56.
9. Exhibit 3, p 21, cl 4.2.
10. Exhibit 3, p 26, cl 11.1(c).
11. Exhibit 3, p 25, cl 11.1(a).
12. T23/43-46.
13. Exhibit 3, Tab 20, pp 103-105.
14. Exhibit 3, Tab 29, pp 124-157.
15. Exhibit 3, p 126.
16. Exhibit 3, p 138.
17. Exhibit 3, p139.
18. Exhibit 3, p 140.
19. Exhibit 3, p 140.
20. Exhibit 3, p 88.
21. T85/1-8.
22. T89/48-90/6, T91/49-T92/2.
23. See e.g. Exhibit 1.
24. See Exhibit 3, pp 77, 80, 84, T99/3-25, T106/31, 46.
25. T106/35-T107/5.
26. Exhibit 3, p 84.
27. T175/34, T191/19-31.
28. Exhibit J.
29. Exhibit 3, p 90.
30. T22/3-21; T38/11.
31. T192/48-T193/20.
32. Exhibit J.
33. Exhibit 3, p 107.
34. 27/3/18, T26/23-27.
35. T38/25-29.
36. Exhibit J.
37. T178/29-40; T197/25-30.
38. T183-T184 especially T184/27.
39. Exhibit 3, p 107.
40. T94/28.
41. T86/19-36.
42. T85/1-8.
43. T90/1-6.
44. T91/49-T92/2.
45. T107/36-40.
46. T107/28-34.
47. T108/33-36.
48. T110-112.
49. T109/24-35.
50. T175/50.
51. T176/25-30.
52. T176/42.
53. T176/47.
54. T177/4.
55. T177/18.
56. T194/44.
57. T179/15-20.
58. Exhibit J, T 191/38.
59. T178/30.
60. T179/8.
61. T199/45-50.
62. T200/15-30.
63. T178/35-37; T183/15-30.
64. T183/10-30.
65. T184/33-38.
66. T178/29-T179/13.
67. 28/3/18, T24/34-39.
68. 28/3/18, T24/9-12.
69. T190/5-45.
70. See s 64(3) of the Evidence Act 1995.
71. T191/38.
72. T176/28-30.
73. T195/37.
74. T190.
75. (1961) 106 CLR 112 at 115.
76. See J J Spigelman, 'Negligence: The Last Outpost of the Welfare State' (2002) 76 ALJ 432, 441.
77. See [35] above.
78. S 5B(2), CLA.
79. S 5B(2)(a), CLA.
80. S 5B(1)(b), CLA, see also Benic v State of New South Wales [2010] NSWSC 1039 at [101(c)].
81. See [18] for the steps.
82. See CLA, s 5 definition of "harm".
83. Exhibit J.
84. Exhibit J.
85. T184/22-27.
86. S 5B(1)(a).
87. See Garzo v Liverpool/Campbelltown Christian School Limited & Anor [2011] NSWSC 292 at [70].
88. See at [35].
89. Roads and Traffic Authority of NSW v Dederer (2007) 234 CLR 330 at [59].
90. Exhibit J.
91. Exhibit 3, p 149, 5.5.2.3.
92. See Exhibit C, Exhibit D and Exhibit 3, pp 88, 107.
93. T32/10.
94. T56/35-42.
95. At [28]-[30].
96. S 5C(b), CLA.
97. T84/4-23.
98. T86/34-36.
99. T107/35-40.
100. T51/35.
101. T46/13-18, see also Exhibit 3, pp 88, 107.
102. T194/44.
103. T107/28-40, T112/26-41.
104. T31/49-T32/5.
105. T47/7.
106. Exhibit G.
107. T190/5-45.
108. Issues, West Cliff, 3(1), (underlining added).
109. Cf Warren Fitzgerald v The Nominal Defendant [2018] NSWDC 175 at [85]-[92].
110. See Wallace v Kam [2013] HCA 19 at [16].
111. T46/40-46.
112. T51/47-T52/4.
113. T52/2.
114. T68/45-50.
115. Cf 10 to 12 mm on Exhibit J, p 1 with 6" or 8" on p 2.
116. Cf T195/24.
117. Exhibit 3, pp 68-71, T97/43-T98/7.
118. T176/39-T177/18, T177/11-18, T194/42-50, T195/22-37.
119. T47/7, T111/31-38, T112/26-41.
120. T31/8, T31/49-T32/11, T38/4. 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. Decision last updated: 28 August 2018