Coulthurst v Miles

Supreme Court of NSW|2019-09-12|Before: Campbell J

Judgment

The plaintiff, Mr Coulthurst claims damages for injuries he suffered as a result of a work site accident on 6 April 2016. Mr Coulthurst was engaged by Mr Miles, the first defendant, to work as a sub-contractor on the construction of Mr Miles's new home at Knockrow on the NSW North Coast. Mr Coulthurst was a tradesman carpenter with many years' experience in home building work. He was also the holder of a builder's licence but on this job he was paid an hourly rate to provide his labour, carpentry skills and local connections in the home building industry in the construction of the house. Mr Miles was undertaking the construction work under an owner-builder's licence. He is a chartered accountant by profession with a background in investment banking. He remains actively involved as a board member with two private equity funds. Mr Miles is a co-director of the second defendant, Ballyshaw Pty Ltd. The company conducts a macadamia orchard and beef cattle grazing enterprise on the 320 acre property on which the house was being built. Many of the contractors involved in the construction of the house, including Mr Coulthurst, were paid out of the company's accounts. The company owns the Kubota excavator which Mr Miles was operating when Mr Coulthurst's was injured.

Circumstances of the plaintiff's injury

The following narrative of fact, derived from evidence I accept, had become uncontroversial by final submissions. On 6 April 2016, Mr Miles, Mr Coulthurst and Mr McCaffrey, another sub-contracting carpenter, were working to place a steel beam upon two upright steel columns to complete the portal for a proposed steel sliding door. I interpolate that the sliding door was to connect the interior of the house with a proposed timber patio or deck. The steel beam was 7.4 metres long and weighed approximately 260kg. In preparation for lifting the beam into position, Mr Coulthurst and Mr McCaffrey slung the beam from a hitching point on the excavator. Mr Miles then operated the excavator to lift and position the beam. By then Mr Coulthurst and Mr McCaffrey had each climbed a stepladder at either end of the door opening for the purpose of applying temporary supports to hold the beam in place until it was welded in position by the steel fabricators later.
On the evidence of both Mr Coulthurst and Mr Miles, Mr McCaffrey's end of the beam went into position first and the process had gone smoothly. At this end there was a short metal plate welded between two steel posts comprising this column. The gap between these steel posts formed the entry to a cavity into which the future door panels would slide on rails when opened. This end of the beam was seated neatly on the plate without difficulty.
The situation was different at Mr Coulthurst's end. There was a single steel column extending above the height at which the beam was to be welded into position. A timber post, or prop, had been fixed with F clamps to the steel column forming this end of the portal. The timber prop was the vertical part of the temporary support for the beam before it was welded. The prop was a 90mm x 45mm x 2900mm timber post. Its 90mm face was clamped flush with the column. It was intended to sit the underside of the beam on top of the timber post. Lateral support was to be provided by means of two timber cleats in a horizontal plane, one on each sided of the beam held in place by two "F" clamps. One "F" clamp was to be positioned towards either end of the cleats. One clamp was to hold the cleats hard against the sides of the beam and the other to hold them against the steel column at the western end of the north facing doorway. This arrangement was assembled by Mr Coulthurst while the weight of the beam was taken by the excavator. Once the beam was temporarily secured in position by these means, the slings would be released.
After Mr McCaffrey's end was in place, Mr Miles drove the excavator forward slightly to position the beam at Mr Coulthurst's end. But the beam was carried towards Mr Coulthurst past the line of the timber prop and steel column by "a small distance" (124.10T), and Mr Coulthurst pushed the beam to guide it back to its correct position over the prop (124.15T). It appears that the underside of the steel beam was not then recumbent on the timber post. There was a small gap of about 10mm between them. At this point the beam was held stationary by friction between the end of the beam and the face of the steel column which was, as I have indicated, somewhat taller than the timber post. While the beam was in this position, Mr Coulthurst moved his ladder closer to the beam and fixed the cleats and clamps into place from the stepladder, an operation that obviously involves no small degree of difficulty and ambidexterity (127.5-33T). Mr Coulthurst described it as "a bit of a fiddle" (36.30T). But said, "I mean I've done up so many of them…you learn it - a way to do it" (128.40T). Having completed this task he moved the stepladder back to his original position to get out from under the beam before it was lowered on to the prop.
The various operations of the excavator during the lift were brought into play by means of hand signals from one or other of the carpenters. Although, there is some contention as to which of them signalled Mr Miles at this point, and the sightlines available to the three men, it appears to be accepted now that a hand signal was given to Mr Miles to lower the beam the very small distance necessary for it to sit on the timber prop before the slings could be removed.
At this point in the operation the beam moved, the cleats and clamps released and the beam swung out towards Mr Coulthurst causing him to fall from his ladder before swinging back and knocking the timber prop over, dislodging the clamps holding it against the steel column in the process. How and why this occurred is the principal factual issue in the case.
Mr Coulthurst landed awkwardly suffering a serious fracture of his left leg and a back injury. Mr Coulthurst is adamant that the swinging beam knocked him from his perch on the ladder. The defendants put that its sudden and unexpected movement towards him caused him to lose his balance and fall. This particular issue may make little difference to questions of liability and the nature and extent of Mr Coulthurst's injury and its consequences, except to the extent that the distance travelled by the beam may have something to say about the nature of the forces involved, a potentially significant issue.

Description of Mr Coulthurst's injury

It is fair to say that the plaintiff's subsequent and consequent medical deterioration has been of nightmarish proportions, which he and his wife have borne with an entirely admirable stoicism. His severely comminuted fracture of the left tibial plateau and a fracture of his proximal left fibula required internal fixation with metal plating, screws and bone grafting. As can happen Mr Coulthurst contracted a serious post-surgical staphylococcus aureus infection which proved stubbornly resistant to the high-powered antibiotics with which he was treated. The raging infection or its aggressive treatment, on Mr Coulthurst's case, led to infective endocarditis of his aortic valve and total renal failure requiring dialysis. The connection of the latter conditions to the original injury is contested. This potted summary does not cover all of the medical woe that has befallen Mr Coulthurst but suffices for present purposes.

Separation of the question of liability and damages

Soon after the development of his condition of renal failure in about mid-2019 Mr Coulthurst applied for expedition of the hearing on the ground of his precarious prognosis during the initial stabilisation phase of dialysis. The order was made by Walton J on 9 August 2019 and the matter was thereafter case-managed by Fagan J who fixed the matter for the hearing of the lay evidence in the case over three days commencing on 10 September 2019 on the far North Coast because the plaintiff was unable to travel to Sydney. The expectation was that expert evidence would be heard in Sydney on a date to be fixed thereafter.
The matter was allocated to me for hearing and after taking the available evidence in Byron Bay I made directions for the exchange of further reports from the liability experts having regard to the lay evidence given and for the service of the defendants' expert nephrology evidence dealing with the renal failure issue which was not then to hand. Due to this latter necessity and the limited availability of experienced senior counsel the earliest available court dates suitable to the parties were three days commencing on 16 December 2019. The plaintiff appeared to have stabilised on dialysis and the additional delay while regrettable did not appear critical.
The matter was brought back before me on 6 December 2019 as the defendants' qualified nephrologist had died suddenly before providing his report and the parties were unable to agree on the appropriate steps for future case-management. After discussion it was agreed that the hearing dates would be preserved to take as much further evidence as was available, the defendants would have the opportunity to qualify another suitably experienced nephrologist to give expert evidence and the matter would be further adjourned to allow all proper preparations to be finalised. Again, having regard to the complexity of the medical issue, the need for the plaintiff's lawyers to consider and respond if necessary to the defendants' expert, the Court's roster and the availability of counsel three days from 30 March 2020 were set aside.
The matter proceeded to further hearing on 16 and 17 December 2019 when expert liability evidence and lay evidence on quantum was heard. After the adjournment, during January 2020, Mr Coulthurst underwent surgery to address his cardiac issue and, as if not enough had befallen him already, suffered a stroke as a consequence. While I was informed when the matter came before me for further directions on 13 February 2020 that Mr Coulthurst's rehabilitation from his stroke was progressing favourably, it was accepted by senior counsel for the parties that the need to address this latest complication rendered it impracticable in the extreme to attempt to deal comprehensively with quantum issues at a hearing commencing on 30 March 2020. It was accepted that the interests of justice and the overriding purpose governing the conduct of civil litigation would now be best served by deciding liability separately. Accordingly I ordered that issues of quantum be severed and directed that the questions of duty, breach and contributory negligence be decided separately and in advance of the trial. I brought the hearing forward from 30 to 11 March 2020, when, all liability evidence having been received, counsel addressed on the separate questions.

The issue and summary of argument

The issue of liability is said to turn on the mechanism by which the beam swung out from its temporary supports towards the plaintiff, and whether it travelled far enough to actually strike him. Mr Doherty SC, who appeared with Mr H Summerville and Mr M Hammond for the plaintiff, submitted that this is a case of casual negligence on the part of Mr Miles in the operation of the excavator. Mr Doherty argued that Mr Miles lowered the boom of the excavator without due care causing the beam to: move in its lateral supports and dislodge them; swing out at force, knocking the plaintiff from the ladder; and swing back again dislodging the timber prop. Clearly a plant operator owes a general duty to exercise reasonable care in operation of the plant to avoid unnecessary risk of personal injury to other persons engaged in the work within the sphere of operations arising out of the movements of the machine or its load. Mr Doherty also argued that the defendants owed Mr Coulthurst a non-delegable duty of care having regard to the relationships of occupier and entrant, and owner-builder and contractor.
Mr Greenwood SC, who appeared with Mr J Lee for the defendants, argued that it was Mr Coulthurst who was in charge of the operation. It was the shortcomings of the system of work devised and instituted by Mr Coulthurst which caused the beam to swing out. He argued that the plaintiff was the only person among the tree actual participants who was familiar with the work that was necessary for the fitting of the beam. Mr Coulthurst had been in discussions with the engineer in relation to the design of the steel columns, the steel beam and their proposed means of connection to the building. To support this argument Mr Greenwood relied on the following evidence of the plaintiff (Exhibit G, Plaintiff's evidentiary statement, Annexure A at [32]): Neville asked me to liaise with the engineer because I knew the engineer, and I had an understanding of how things fit together (and could be joined together) which Neville simply didn't have.
Mr Greenwood further contended that it was Mr Coulthurst who dealt with the steel fabricator and liaised with him regarding changes required to accommodate the practicalities of installation. And ultimately that it was Mr Coulthurst who supplied the clamps, fashioned the prop and cleats and did all the work with the assistance of Mr McCaffrey (112T; 150-151T). Mr Greenwood emphasised Mr Coulthurst's active involvement in the whole process. He pointed out that the plaintiff effectively worked on the building site full time, 40 hours or more a week. Mr Greenwood argued that the clamps were worn and liable to fail more readily than newer clamps if the beam moved in rotation, as, he submitted, was virtually inevitable, during the process of lowering it on to the prop.
Mr Greenwood argued that while it may be difficult to identify a particular act or omission of Mr Coulthurst which caused the accident, Mr Coulthurst had a direct involvement in each of the circumstances that combined to bring about the accident and his injuries. It was submitted that there is no evidence that anything done, or omitted to be done, by Mr Miles caused them.
Some emphasis was placed upon the consideration that the beam was successfully lifted into position without incident the day after Mr Coulthurst's injury, and in his absence. Mr McCaffrey working with the assistance of one of Mr Miles's sons and with Mr Miles operating the excavator again, while employing what I would regard as the same basic concepts as Mr Coulthurst, fashioned temporary supports of a sturdier kind which were securely fixed to the steel column and the timber wall frame.
A point of primary fact in contention between the parties is whether the beam moved at Mr McCaffrey's end when it swung out towards the plaintiff. Mr Greenwood advanced the argument on behalf of the defendant that the steel beam lacked significant elasticity and could not move at one end and not the other. Mr Doherty submitted on behalf of the plaintiff that the beam did not need to move on Mr McCaffrey's end but rather that when the force was applied to the beam it pivoted at one end.

The evidence of the lay witnesses

Each of Mr Coulthurst, Mr McCaffrey and Mr Miles gave oral evidence. The case is notable for the consideration that notwithstanding the provision of detailed witness statements about the circumstances of the accident by each of Mr Coulthurst and Mr Miles, the full facts set out in my narrative above did not emerge until the hearing itself. For instance, there was no mention in the statements of Mr Coulthurst's end of the beam travelling beyond the steel column and prop when Mr Miles first attempted to seat it on the prop. Moreover, as I point out below, Mr Miles maintained in his statement, and initially in cross-examination that the excavator was stationary and he was not manipulating the levers to operate its lifting apparatus immediately before or when the beam swung out towards Mr Coulthurst causing him to fall from the ladder. Mr McCaffrey had previously preferred not to become involved in the legal process. I make no criticism of him in this regard. He declined to be interviewed formally for the purpose of the proceedings and provided only a very short statement dated 15 May 2017 which was admitted as Exhibit 10.

Mr Coulthurst

Annexure A to Mr Coulthurst's evidentiary statement of 17 May 2019 (Exhibit G) is a separate statement of 2 August 2018 which deals with the nature of his engagement by Mr Miles and the circumstances leading up to and relating to his accident. He confirms that Mr Miles asked him to liaise with the engineer and the steel fabricator. The doorframe was designed by the door manufacturer, Martins Joinery, but the structural members were designed by the civil engineer engaged by Mr Miles, Peter Lucena. Mr Coulthurst acted as a go-between on behalf of Mr Miles. Mr Coulthurst said his input was to provide what I take to be the actual onsite measurements and to explain Mr Miles's wishes in relation to functionality to the engineer and the steel fabricator. Mr Coulthurst said (see [16] above): I was not responsible for finalising the design or for having any input into the design other than checking measurements and points for attachment. Neville asked me to liaise with the engineer because I knew the engineer, and I had an understanding of how things fit together (or could be joined together) which Neville simply didn't have. (Exhibit G, Annexure A at [32]).
There was some difference between Mr Coulthurst and Mr Miles about whether the prospect of hiring a Franna mobile crane for this particular lift had been discussed by them (Exhibit G, Annexure A at [37]-[42]; 106.45 - 108.5T). Mr Coulthurst said that it was only a brief discussion and Mr Miles was confident he would be able to lift the steel beam. Mr Miles agreed there had been a discussion about the use of a crane, but in the context of whether the steel fabricators' truck could off-load the components of the frame close enough to the northern side of the construction site because recent rain had made the unpaved driveway slippery (191.20-.38T). Mr Miles was quite confident in his ability to do the lift. He said (191.35T): The, the discussion regarding the - whether to use the excavator or not - there was no discussion because we'd used it quite successfully to put in place I think it's 16 odd beams and columns prior to that. So, there was - this was not a particularly difficult or different proposition. Both agreed that the previous lifts had involved hardwood beams and columns. The dimensions of the timber beam put in place at the portal of the entrance to the house were 300mm x 300mm x 7m.
In his statement (Exhibit G, Annexure A at [70] - [82]) Mr Coulthurst omits to state that part of his account which includes his end of the beam travelling beyond the line of the steel column and timber prop after Mr McCaffrey's end was put in place. Rather, after some manoeuvring, he said the beam was resting on the timber prop when he applied the lateral supports involving the cleats and F-clamps. His account in Exhibit G is that his end swung out without warning when Mr Miles was lowering the excavators lifting apparatus to slacken the slings to allow them to be removed.
In his evidence-in-chief, Mr Coulthurst said that Mr Miles brought the beam to Mr McCaffrey's end first and Mr Miles "had to come in a bit further to get my end" (26.10-.25T). He said when Mr McCaffrey's end was on the steel plate (27.38T): …mine was a bit short, but it did end up coming in, and it end up coming just a little bit too far. I actually remember having to push it back (28.4T). As I have said already, when Mr Coulthurst pushed the beam back, there was "a small gap between the underside of the beam and the temporary column" (44.20T). Mr Coulthurst then applied the cleats and F clamps. After he had applied these temporary supports, Mr Coulthurst said (46.36 - .50T): Well, the slings were still carrying all the weight. I don't know how much [Mr McCaffrey's] end was being carried by the slings, but the end - my end was definitely being carried by the sling. Because it wasn't resting fully on this support, so the weight at my end was being carried by either one of the slings, or possibly, you know, both of them. I'm not too sure, but. So, to let - to be able to take the slings off, they have to be slack. You can't take them off while they're all [taut]. So, so, he had to lower the beam, or, or lower something or other, or lower the beam. I don't know what operation it was, but lower the beam so that the, the slings would slack, the beam would rest on its support, would be resting fully on the supports at both ends. And then the next step would've been to take the slings off and have the, the steel fabricators come in and weld it up. That was the plan.
There is a difference between Mr Coulthurst and Mr Miles about who gave the signal to lower the beam. Mr Coulthurst said he had no clear line of sight to Mr Miles because the lifting mechanism of the excavator obscured his vision. On the other hand, Mr Miles said that he couldn't see Mr McCaffrey and he was taking signals from Mr Coulthurst. The difference matters not because both agree a signal was given.
In any event in Mr Coulthurst's account, a signal was given to Mr Miles "to lower the beam" (46.10T). He was asked what happened next and said (47.10T;47.35-.50T): Well the next thing I see - and I, I, I think I saw - and I say I think I saw - I think I saw the boom move a bit. But I definitely saw the beam just swing towards me. …. Yeah it, it was, it was that quick that - it happened that quickly that it swung towards me, I believe I put my arms up to protect myself or shield myself but then I remember falling with the ladder, so the ladder sort of - the ladder - toppled - that being an A frame, it toppled that way with me standing on one side, it toppled like that (indicating). …. It all seemed to happen in slow motion.
He did not see what happened to the cleats and F clamps, but he saw the beam swing back and clip the timber prop, knocking it "outside [the perimeter of the house], and I remember seeing the clamps [restraining it] go outside as well".
In cross-examination Mr Coulthurst agreed that he had devised the system for temporarily supporting the western end of the steel beam. He was criticised, by implication, on the basis that the prop supporting the weight of the steel beam, "in terms of it being a system, it was really just a bit of wood clamped to the steel column to support the beam" (112.46T). But Mr Coulthurst regarded that as its merit: as a system it was "nice and simple" (113.1T).
Mr Coulthurst took issue with the suggestion that he was responsible for the state of the slings. Mr Coulthurst said that the slings did not belong to him (other evidence established they belonged to Mr Miles). He did not regard the attachment of slings to a load and lifting device as within his expertise (114.1T). His evidence was, at least initially when other lifts were performed, that Mr Miles had "directed" Mr Coulthurst and Mr McCaffrey "as to how we put them on" (113.45T). Sometimes Mr Miles's son had been involved in the previous lifts (114.20T). And sometimes Mr Miles or his son "did them" (114.22T). I interpolate that there's no suggestion that the method or manner of slinging the steel beam had anything to do with what happened.
In cross-examination on Exhibit G Mr Coulthurst denied that he reached out to pull the beam towards him when first dealing with his end. He said (123.5-.10T): [If] something's being slung, you don't try and control it by pulling it towards you, you let the machine bring it into place. But you just try and steady it. It's just making sure it doesn't start wobbling around and moving too much and hitting things, that it shouldn't do. He described this as "guiding" the beam into place (123.20T).
He was challenged about his evidence that the beam "came forward and passed the line of the column" (124.5T) as it was not in his statement. He accepted that but said, "OK, well it should be" (124.23T). He firmly maintained that he had an actual recollection of the details of the event he had given in his evidence-in-chief, some of which were not in Exhibit G.
Mr Coulthurst denied that when the beam moved towards him after he had assembled the lateral supports he "recoiled without it actually touching" him (134.19T). He answered (134.20T): No way. No way. The beam came - it hit me. It literally pushed me. It wasn't just … a slight movement and I was like got a shock. It definitely wasn't that. It literally pushed me. … And I'm a million per cent certain of that.
Mr Coulthurst was cross-examined about the suitability of the F clamps for the task. In particular it was put to him that they can easily dislodge if the pinch point between the bar and the moveable jaw becomes loose (134.30-.35T). To understand the propositions being put, I reproduce a photograph taken in my chambers of Exhibit 14, a model produced by Dr Casey to illustrate the operation of F clamps and Exhibit C, one of Mr Coulthurst's smaller F-clamps of the type used by him to secure the beam. Mr Coulthurst thought the loosening of the pinch point would only occur if the clamp took a direct "hit or a … knock" (134.38T).
This line of cross-examination culminated in the following question and answer (136.26-.46T): Q. What I want to put to you is that a real possibility as to what happened here is that when you had pushed it back, this beam was not square on the column at all, that's why it stuck there or it had rotated, by reason of it being pushed back against the slings, you'd applied the clamps without being able to see or observe that it was not flush, and that when the weight was taken, obviously that is when the beam was lowered, it rotated, the clamps were released and so the beam came back towards you, as it had before, before you had pushed it back, what do you say about that? A. I - one, I, I - if I'm understanding what you're saying, the beam and the column are the same width. So, when the beam is being clamped with the blocks of wood, it's pulling them into the same plane. So, they're - one, they're, they're both the same [width], so they're in the same plane. The column was hard up against the - the beam was hard up against the column. And there was a small gap between the top of the column, the top of the temporary post and the underside of the beam. The thing about rotation, I, I, I can't see how that would've happened. I don't think there was any - I would never have considered any possibility of rotation at all. It all - and it all was - it was looking - I mean the column and the beam were, were square, and the clamps were definitely well secured. And I know the blocks of woods were well secured.
Mr Coulthurst rejected the proposition that the F clamps may have been dislodged by the beam moving off the timber prop. It was implicit in this question that the 45mm wide aspect of the prop perpendicular to the steel column was insufficient to support the beam (136.50-137.20T). Mr Coulthurst was prepared to accept that a significant movement could have been sufficient to release the F clamp, but he did not regard that possibility as consistent with the movement of the beam "straight towards" him (137.13T). He agreed that the beam moved towards him in the same direction as Mr Coulthurst had pushed it away originally (137.16T). When he pushed it away, he had been standing about an arm's length (indicated to be 600mm) away from the beam. He was not "pushing it back three metres" (137.22T). He pushed it "possibly 100mm" (137.20T).

Mr McCaffrey

In his statement of 15 May 2017, Mr McCaffrey gave the following account (Exhibit 10): [Mr Coulthurst] and I attached slings around the beam into position while [Mr Coulthurst] and I waited on our ladders on each end of the beam. As we were attempting to set the beam, [Mr Coulthurst's] end swayed towards him. I was at the far end of the beam (approximately 7m or more away) and did not see precisely what caused [Mr Coulthurst] to fall but he had become entangled in his ladder. I do not understand Mr McCaffrey's use of the conjunction "while" to connote that he and Mr Coulthurst attached the slings to the beam while they were on their ladders. Rather, he meant "and then" they took up their positions on their ladders.
He expanded upon this account in his evidence-in-chief in the following manner (158.25-.35T): The guys that dropped … the beam off to the job, they drove in alongside the building and then that had a [Hiab], which is the crane on the back of a truck, and they pretty much lifted it up to pretty much where it was going to go. So then [Mr Miles] had to pick it up and move it into position, so it gradually came up and then he moved in, and then it came down, and somewhere amongst that happening it just came down. I … was sort of fixed on where I was. It was a 500 kilogram beam or so. How [much] it weighed, I'm not quite sure. I was pretty much looking at where I was, keeping myself out of danger. I turned around and … [Mr Coulthurst] was falling, and then I quickly ran over to him and, and tried to help, yeah.
On further questioning he said that all three of the men were "trying to communicate, but more so [Mr Coulthurst]" (158.38T). He was concentrating on his end of the beam and he said, "And then … while all that was happening, it just happened in an instant" clicking his fingers to indicate the instantaneous nature of the injurious event (158.40-44T). He didn't remember seeing what Mr Coulthurst was doing at his end because he "wasn't taking [his] eyes off where [he] was and the beam, and looking over and trying to communicate, but mainly I was like trying to keep myself safe and working safe" (159.2-.4T).
Mr McCaffrey gave evidence about the successful positioning of the beam the following day involving him, Mr Miles and one of Mr Miles's sons (159.10ff). As I commented earlier, the concept was similar, but the construction sturdier with all of the supports being put in place before the beam was lifted again. Rather than clamping it, he screwed the 90mm x 45mm prop so it was fixed to the column. He screwed a second prop of the same dimensions onto the first prop which doubled the depth of the footprint for the beam provided by the prop at the western end. The cleats were also fixed, rather than clamped, to the timber wall frame and an angled prop was fixed with screws into the end of each cleat and battered from ground level. He said, "So when the beam came down it actually had a slot. I wasn't taking any chances after seeing that accident" (162.6-.7T).
When asked in cross-examination whether his end of the beam moved out of position at any stage, he answered (at 164.10T): No. I just remember like running down my ladder, 'cause [Mr Coulthurst] had obviously hurt himself, so I just remember going to help.
Without objection from counsel, I asked the following question (165.18T): Q. Okay. Can I just ask you something about what you've said you did on the second day. I mean, I'm just asking questions, I want to hear what you say about it, so don't take any suggestion from me as meaning anything. I'm not suggesting anything to you. But having regard to what happened to [Mr Coulthurst], did you devise a kind of belt and braces type approach to this task? A. I had to, yeah.
On re-examination he was asked (165.47T): Q. Did you have a concern about that lateral movement? A. Obviously, yes, after [Mr Coulthurst] had hurt himself, yep.

Mr Miles's Evidence

In his evidentiary statement of 5 September 2019, Mr Miles stated that the company had purchased the Kubota KX 121-3 excavator in 2013 (Exhibit 11 at [21]). He used it extensively around the property to clear out drainage trenches, build roads, lift things, dig holes and pull out trees (Exhibit 11 at [21]). In cross-examination he said he had "probably accumulated, at the time of the accident some 600 hours" operating the excavator (168.20T).
He was quite confident that the excavator "would be able to do the job" of lifting the steel beam into position because he, Mr Coulthurst and Mr McCaffrey had "already lifted a number of probably heavier beams in place with the same sort of height elsewhere in the house" (170.5T). Later Mr Miles said "we'd used it quite successfully to put in place, I think it's, 16 odd beams and columns prior to that" (191.35T).
By April 2016, the construction work "had progressed well". "The framing, windows, roof and most of the outside hardwood cladding was complete" (Exhibit 11 at [28]). As I have said (at [2] above), the task at hand when Mr Coulthurst was injured was the erection of the steel frame "for large opening doors that would lead onto a deck" on the northern side of the house (Exhibit 11 at [29]). I have reproduced below the plan for the northern elevation of the home, part of Exhibit 5. The large sliding door and deck are depicted on the east (left) of the image. The deck was part of stage 3 of the works and had not yet been built when the accident happened.
Mr Miles said that he was called for the lift around lunchtime on 6 April 2016 (Exhibit 11 at [31]). The beam was elevated on timber about 10 metres from the proposed doorway (Exhibit 11 at [31]). He said he performed a check, I infer by elevating the lifting apparatus of the excavator, "to ensure the excavator arm could reach the height where the steel beam was to be positioned" (Exhibit 11 at [33]).
The question of the reach of the excavator was a matter of some contention between the expert engineers, Mr Waddell and Dr Casey, an issue which I will consider later in my decision. However, as the height and nature of the operations carried out by Mr Miles (or not) are relevant to what happened and to Mr Miles evidence I reproduce figure 3 and 4 below from Dr Casey's report of 31 May 2019 (Exhibit CB 31; p.343 and 345). I will also explain the relevance of Dr Casey's reference to "the quick release" below. Figure 3 is reproduced now:

Figure 3

From Figures 3 and 4, and the evidence generally, I infer that the lifting apparatus consists of three hydraulically operated parts: the lowest boomerang shaped part is called the "boom". Although there is a bend in the "boomerang", it is rigid and does not articulate. At the end of the boom and above an attached articulation point, or elbow, is the "dipper arm." Beyond the dipper arm is the tip which includes the "quick release hitch". Buckets and other implements are attached to the quick release hitch by a D-shackle which is fitted through the lifting eye on the quick release hitch. Figure 3 depicts a hook, but there is now no issue that the beam was slung by attaching the slings through the D-shackle.
Although it's evident that Mr Miles had a certain amount of experience operating the excavator for various purposes, he was not familiar with all of its functions or with the terminology applicable to the various components of the hydraulic arm or lifting apparatus.
It's apparent from Dr Casey's report, Exhibit CB 31, and from the illustrations he provided as set out above, that there are essentially three moveable parts making up the arm as I have described above. Mr Miles was unfamiliar with the use of the quick release mechanism as part of the excavator's lifting apparatus. The expert evidence is that the quick release mechanism can be operated independently of the dipper arm and the boom to lower a load in a vertical plane without an arcing movement of the load (Exhibit CB31, p.344-5, [22]-[24]). At 168.49 - 169.30T the following appears in cross-examination: Q. On the day of the accident, immediately before it occurred, you didn't use the quick release mechanism, did you? A. I didn't use the what, I'm sorry? Q. The quick release mechanism, on the excavator? A. I - I'm not sure of the question. What - I don't understand what you're asking. Q. Do you know what the quick release mechanism is? A. I do, but it - I wouldn't have used it because the bucket would've been removed. So, there was nothing to quick release, if you get my meaning. Q. If the bucket's not on there-- A. No. Q. --do you say you couldn't use the quick release? A. Well, I wouldn't use the quick - I, I don't understand - the quick release is a mechanism that either puts the bucket on or takes the bucket off. So, the bucket had already been taken off, and then there's a ring on the excavator, which, which you can attach things to. So, the quick release is, is - I'm not sure it's relevant. Q. It doesn't have any work to do if the bucket's not on, is that what you're saying? A. It, it - the, the quick release mechanism is a, is a, is a fork which holds the bucket. So, if there's no bucket, the fork is just sitting there, because it's not holding anything, so it's not releasing. The idea is that the quick release either picks the bucket up or lets it go. The, the, the actual attachment for the beams, or if you've got to pick something up, you would use - I think it was tendered earlier - was the D-ring which has a ring and it's just the - you put that - you put the straps on. The quick release has nothing to do with the lifting process.
It was also quite clear from the cross-examination that Mr Miles used the expression "the boom" instead of the dipper arm and regarded what is referred to as the boom, perhaps, as "the entire arm" (178.24-179.22T). From the same passage Mr Miles indicates that the dipper arm is moved by manipulating the handle or lever to his left and the boom by manipulating the handle or lever to his right. He said, "effectively you can get [the load] to go straight up and straight down" by simultaneously operating the handles in opposite directions (180.1-.15T). He said that co-ordinating both levers "requires … some practise" (180.30T). He accepted that absent this co-ordination the dipper arm and tip would move in an arc, as illustrated by Dr Casey's figure 3.
Mr Miles said that after Mr Coulthurst and Mr McCaffrey had attached and checked the slings, guide ropes were attached to both ends of the beam to keep it stable as it was moved to the house (Exhibit 11 at [34]). Neither Mr Coulthurst nor Mr McCaffrey mentioned the guide ropes. Nothing turns on this as it is not said by any party that such guide ropes played any part in causing the accident, or might have prevented it. I am unable to make a finding one way or the other about their presence.
When the excavator and its load were close to the house, Mr Miles stopped the excavator and Mr Coulthurst and Mr McCaffrey climbed their ladders. According to Mr Miles, Mr Coulthurst was providing directions by hand single. Mr Miles said, "I did as instructed, very slowly, until told to stop" (Exhibit 11 at [36]). He said he was waiting for further direction (Exhibit 11 at [37]) and said (Exhibit 11at [38]): "I do not know what caused [Mr Coulthurst] to fall. I was in the cabin waiting for his directions when I saw the beam sway as it swung from the supports and then saw [Mr Coulthurst] lose balance and fall awkwardly. I was not moving the beam with the excavator immediately before or when he fell."
After Mr Coulthurst's fall, Mr Miles noticed that the beam was not supported on either column (Exhibit 11 at [39]). He raised it slightly, moved it away from the house, lowered it and left the excavator to assist (Exhibit 11 at [39]).
In cross-examination, Mr Miles said that he was satisfied that the beam was close to being in place and he was waiting for "the final hand signals from [Mr Coulthurst] as to what … to do" (178.10T).
He said he did not "believe" that he was operating the levers to lower the beam when Mr Coulthurst "was knocked off his ladder" but he did not recall precisely how that happened (182.6-.10T). At that point he was unsure whether the beam was "fully in position or nearly in position" because he could not see from where he was (182.45T). Mr Miles accepted that the "chocks" or cleats to prevent lateral movement were in place (183.10-.25T) and he accepted that after Mr Coulthurst fell, the beam swung back (183.38-.40T). Initially he was unable to say whether it did so on a "lower plane" (183.50T) but he did recall "seeing one of the pieces of wood fall, and it might well be that they were just simply not … sufficiently … secured" (183.44-45T).
Mr Miles was cross-examined on the contents of what became Exhibit J, the defendants' solicitors' letter qualifying Dr Casey to give evidence (184T). Having reiterated his belief that he wasn't moving the levers when the accident happened (184.10-.25T), Mr Miles was asked whether he had "ever [told] anybody that [he was] using the levers of the excavator to lower the steel straight down at the time [Mr Coulthurst] came to grief?" He reiterated, "I don't believe so, no" (184.30T). The account in Exhibit J, so far as is presently material, is as follows: [Mr Coulthurst] hitched the steel beam to the excavator and directed [Mr Miles] in the movement of the beam onto the vertical posts. [Mr Coulthurst] and [Mr McCaffrey] were standing on ladders leaning on each of the posts and were guiding the steel beam into place. [Mr Coulthurst] alleges that while the excavator was lowering the beam, the beam swung towards him, causing him to jump or fall off the ladder to avoid a collision, resulting in an injury to his leg. At the same time the temporary support clamped to the vertical beam closest to [Mr Coulthurst] became detached. The defendant instructs that he was using the levers of the excavator to lower the steel beam straight down. (Emphasis added).
When asked again about the temporary support clamp to the vertical timber prop becoming detached, Mr Miles said (185.35T): I saw - when, when the beam swung back, I saw the one chock or piece of - a piece of 45 by 90, a length of it fall to the ground. I did see that. I remember that quite precisely. I interpolate when taken with Mr Coulthurst's evidence and the evidence of Mr McCaffrey about screwing the prop the following day, this must be a reference to the timber prop.
When confronted with the statement about him using the levers and asked whether he had instructed the solicitors accordingly, Mr Miles answered at (185.45T): Yes, because it - we were trying to get it in position. But your question earlier was that, was it precisely at the moment that the beam fell, I don't know that. It was - that's the process of getting it into position.
He gave the following evidence at (189.37-.50T): Q. If you had used the levers to lower the beam, that could have caused the beam to sway towards [Mr Coulthurst], couldn't it? A. Could have caused the beam to sway? Q. Towards [Mr Coulthurst]? A. It could [have], but it, it, it might not have. If it - if I'd taken it straight down, it wouldn't have swayed. But I, I-- Q. But if you did it quickly, it would sway, wouldn't it? A. But I didn't do - I, I made no quick movements because obviously it was quite intricate, what was being, being done. Q. Did you try to move it slowly? A. At all times I moved it slowly, yes.
He also said that if he was in the process of lowering the beam, "it would have been with a double movement to ensure that it went straight down" (190.10T). He said that he was not looking to slacken the slings, they were still in the process "of trying to get the beam into place" (190.24T). He agreed that he "probably" told Dr Casey that after Mr Coulthurst fell, he could see that Mr McCaffrey's end had come free (198.17T).

Expert evidence

The expert evidence in the case was a little unusual for litigation of this type. Normally experts in cases like that at hand are called for the primary purpose of imparting to the court enough technical information derived wholly or substantially from their field of expertise, including about standards normally observed in the industry involved, to enable the court to make judgments about the practical content of what reasonable care requires in the particular field of human endeavour in question. Their evidence will also often assist in the determination of questions as to the technical or scientific cause of an event to the extent to which such matters inform questions of factual causation, bearing in mind, that in the end, causation is always a matter for the judgment of the tribunal of fact.
The expert evidence in this case but lightly touched upon one aspect of the first question going to the condition of Mr Coulthurst's F clamps and may have been understood as explaining possible mechanisms in technical terms accounting for the failure of the lateral supports put in place by Mr Coulthurst and the swinging motion of the beam on the release of those restraints. The bulk of the expert evidence led is really investigative in nature, seeking to explain what happened and why in a process akin to accident re-construction. To the extent to which their evidence trespassed upon the ultimate question I bear in mind s 80 Evidence Act 1995 (NSW), and the requirement for all admissible opinions of experts to be demonstrably based wholly or substantially upon the established body of expertise which they profess: s 79 Evidence Act.
And I have also borne in mind that the usual knowledge of mechanical engineers cannot set the standard of care to be observed by a carpenter/builder, or a plant operator for that matter: Dovuro Pty Ltd v Wilkins (2003) 215 CLR 317; [2003] HCA 51, Hayne and Callinan JJ. As McHugh J observed in the same case (at [34]): To hold defendants to standards of conduct that do not reflect the common experience of the relevant community can only bring the law of negligence, and with it the administration of justice, into disrepute. A relevant community may extend, as his Honour made clear, to a community of experts whether of carpenters, builders, plant operators or otherwise. I turn then to deal with the expert evidence.

Mr Waddell's evidence

Mr Waddell gave evidence that the likely cause of the movement of the steel beam towards Mr Coulthurst was the boom being lowered by Mr Miles (225.15-20T). In support of this conclusion, Mr Waddell relied, at least in part, on the assumption that the beam swung out towards Mr Coulthurst and then in a pendulum like movement swung back on a lower plane from its previous position before the movement began. He said that lowering the boom would cause the hitch point to move down vertically and laterally towards Mr Coulthurst's position in an arc like shape, causing the slings and the steel beam to shift off the support provided by the timber prop and swing out, knock Mr Coulthurst off his ladder and then swing back on a lower plane (226.35-50T).
Mr Waddell opined that the height, vertical reach and positioning of the excavator were factors in the cause of the beam swinging out of position. Mr Waddell noted that the height and reach of the excavator were such that the slings supporting the beam were relatively short causing any movement to result in a high forward force on the beam. He also suggested that the position of the excavator could have been important because had the excavator approached the installation from an angle this would have resulted in a forward force on the beam. Mr Waddell accepted in cross-examination his opinion about arcing movement was based on the lifting apparatus of the excavator being at, or close to, its maximum height (250.39T).
Mr Waddell ultimately concluded that on the facts available "we can safely assume that the beam which knocked Mr Coulthurst off his ladder was acted on by an external force" (CB 28 at p.296).
Mr Greenwood put to Mr Waddell that the F clamps used by the plaintiff did not have teeth and otherwise appeared to be loose and worn (230-231T). Whilst, Mr Waddell accepted that some parts of the bar of the F clamp he was shown in court were smooth without prominent "teeth" or notches, and that the aperture of the movable jaw that allowed it to move up and down the bar were loose, he was not prepared however to concede that the F clamps were faulty or worn out (230.25-231.25T).
Mr Waddell accepted that the effect of Mr Coulthurst pushing the beam back into position over the timber prop when it initially travelled beyond that point created an angle between the hitch point on the tip of the excavator and the position of the sling where it supported the beam (249.35T). He said that this would create tension, in the sense of a passive force between the hitch point and the beam transmitted by the slings, which could have contributed to the beam swinging back towards Mr Coulthurst when the lateral supports were forcibly released (249.35T). Other factors relevant to the generation of force on the beam may have included the consideration that the beam was "almost certainly" neither completely vertical nor completely horizontal (250.10T) (but see [72] below). Given the manner of chocking the beam to provide lateral support, by the cleats and clamps, (250.20T), in Mr Waddell's opinion, it would have been impossible for Mr Miles to have lowered the beam completely in a vertical plane (250.30-.35T). This is because of Mr Waddell's view about the height of the dipper head and the tip necessitating an arcing downward movement.
It was Mr Waddell's opinion that it was not possible to lower the boom in other than an arc if the boom is at its maximum height (250.40T). I regard his reference to the boom as a reference to the whole lifting apparatus. He did not regard the quick release mechanism as capable of making a difference if it had been sitting "considerably in an upward direction" (251.7T). In that case it would have "rotated" as it was brought forward in its downward movement (251.10T).
Mr Waddell agreed that "with the quick release mechanism", if it was in a horizontal plane, "you could drop it vertically" (251.35T). However if the length of the slings were reduced to 600mm the tip and therefore the quick release mechanism would have to have been at an angle considerably above the horizontal plane to accommodate that configuration (251.5-10T). Mr Waddell agreed that the degree of arcing involved in lowering the beam one centimetre so it sat on the timber prop was "infinitesimal" (252.5T). He said if the beam only had to go down one centimetre at one end then the D-shackle at the hitching point would only have to have moved "half a centimetre" (252.3T).
Mr Waddell said that the process of clamping would have rendered the beam vertical which meant it could have been lowered without any necessary rotation, depending on the assumption made about the angle of the cleats and clamps (252.15 - .25T). He also agreed that the clamping task undertaken by Mr Coulthurst was not "an easy" one (252.48T). Mr Greenwood asked at 252.47T: Q. I think you described it as having to be an octopus? A. Yes.
Given his views about the necessity of the dipper arm moving in an arcing motion in the circumstances, Mr Waddell said a vertical drop could have been achieved if Mr Miles reversed the excavator as he lowered the lifting mechanism (250.50T). From my understanding of the whole of the evidence this would have been the physical equivalent of Mr Miles "double movement".

Dr Casey's evidence

In his reports Dr Casey had outlined a number of possible mechanisms by which the beam could have swung forward (Exhibit CB 31). He listed these as the excavator moving, the boom on the excavator being lowered, the beam being inadvertently bumped or moved by Mr McCaffrey or Mr Coulthurst, the clamp system that held the beam in place at the Mr Coulthurst end failing; movement of the beam at Mr McCaffrey's end; the beam rolling off the timber post at Mr Coulthurst's end; or the slings slackening in the process of the beam being lowered on to the prop. However, Dr Casey was not prepared to conclude which of the possibilities gave rise to the beam swinging towards Mr Coulthurst in this case, or whether any of them was more likely than one or other (Exhibit CB 31, p.350 at [43]). Quite properly, Dr Casey did not regard the resolution of questions of primary fact as within the province of the expert (Exhibit CB 31, p.349 at [38]). Ultimately Dr Casey gave evidence that the tension to which the beam was subject could not have been released spontaneously; it needed some input of force to initiate the process (274-275T).
In evidence, Dr Casey disagreed with the opinion of Mr Waddell that the swinging forward of the beam was the necessary consequence of lowering the boom. Again, I understood this as a reference to the lifting apparatus generally. Consistently with Mr Miles's evidence, he explained that when the dipper arm and the boom are moved at the same time and in opposition to each other, then the arcing movement of the steel beam which would ordinarily be caused by the movement of one of the dipper arm or the boom alone could be cancelled out (259.2-12T).This could create a movement which is "close to vertical… straight down. You don't necessarily have to generate a movement that's in towards" Mr Coulthurst's position (259.25T) (my emphasis). This expression of opinion was subject to the qualification, "it's possible as long as you've got excess movement", which I take to be a reference to mechanical capacity to move each of the dipper arm and the boom together in opposition (259.23T). I infer that, if say, the boom is "fully pulled back" there may be no room for it to move back further while the dipper arm is pushed forward. In this event the dipper arm would move forward in the arc illustrated in Dr Casey's figure 3 (see [47] above).
As had been intended, during the September to December 2019 adjournment, the experts had been afforded the opportunity of reading the transcript of the lay evidence. It is apparent to me that, given Mr Miles's unawareness of the utility of the quick release mechanism as a means of raising or lowering a load in a vertical plane, Dr Casey was not asked to pursue that possibility in his evidence-in-chief.
In his report of 31 May 2019 (Exhibit CB 31, p.349 at [37]) Dr Casey had said: "In terms of other possibilities, I note that when the beam was installed the day after this incident Mr McCaffrey used alternate chocks and this opens up the possibility that the method of temporarily attaching the beam to the posts was inadequate on the day of the incident, and consequently they let go. I am not saying that this was or was not the case, I am only discussion (sic) what may have occurred." By reference to Exhibit 14, Dr Casey's model, and Exhibit C, one of Mr Coulthurst's F clamps, (see [33] above), Dr Casey expanded on this hypothesis. Dr Casey explained that F clamps and "lots of things" work by a process of cross-binding (260.30T). The fixed jaw is rigidly attached to the bar of the clamp (260.33-.34T). But the moveable jaw when pushed away from the fixed jaw rotates slightly (260.34-.35T). The aperture of the moveable jaw which sits over the bar has a small gap (260.39T). This is necessary to allow the moveable jaw to move along the bar (260.39-.40T). Eventually as the moveable jaw rotates, the internal corners of the aperture make contact with the bar and when the diametrically opposed corners make contact "there's a leverage affect where they dig in" (260.50T). This is effected by tightening the threaded handle. Dr Casey said (261.6-.10T): "In the simplest of terms the corners then dig into the bar and when they dig into the bar they provide friction and they stop the moveable jaw from sliding any more. And that whole process when you get that small rotation, the corners make contract and they dig in and provide friction, that's how all cross-binding works."
The efficiency of the F clamp as a holding device depends upon the maintenance of the force thus established between the jaws. Dr Casey said this was an example of Newton's third law "to every action there's an equal and opposite reaction" (261.15T). Dr Casey also said (261.22T): "… the trouble with this type of cross‑binding type clamp is that it's prone to letting go if the, if the clamping force between the jaws drops away. In this particular case if you're clamping a stiff object, for example, like a thick steel beam or 90 by 45 timber blocks, because they're stiff … in order to generate a lot of force you don't have to compress them very much. So in this particular case the stiffness of the wood, the stiffness of the steel beam would typically require something less than a millimetre in total compression in order to crank the jaws up tight. So in other words from the position that it's currently in with no force between the jaws, (demonstrating) I tighten up the handle and I'm compressing perhaps a millimetres or less between these jaws in order to tighten the clamp up." Given that small degree of compression if the jaws should rotate slightly in the opposite direction, or the object being held rotates slightly (especially where the clamps were not attached perpendicularly), because there is a small diametrically opposed distance, "then that would mean that the tension between the jaws would go to zero and [the moveable] jaw is now free to float; it will let go" (261.40T; 264.41-265.6T).
During his site inspection at Knockrow Dr Casey measured the lifting apparatus of the excavator, the height of the deck which is now built and the height of the underside of the steel beam in the door portal and concluded that the excavator lifting apparatus would not have been at its maximum reach during the lift, contrary to Mr Waddell's assumption (Exhibit CB 31, p 347 at [31]). The relevant measurements are set out in his figure 4 which I have reproduced at [47] above, where 840mm is the average height of the deck from east to west and 2900mm is the height of the underside of the steel beam above the deck. Dr Casey also opined that the consideration that the excavator successfully completed the lift the day after the accident "provides a strong basis" to say "that the excavator was capable of achieving the height" (Exhibit CB 31, p.347 at [31]). On my understanding of it, Figure 4 demonstrates that, with its tip in a more or less horizontal plane with the beam suspended, the underside of the beam can be lifted to a height of 3957mm, 257mm or about 10ins above its intended position.
Dr Casey expressed the opinion that as Mr Coulthurst clamped the cleats to the sides of the beam while it was proud of the temporary prop then the downward movement of the beam may involve a degree of rotation which may be sufficient to cause, especially, a work-worn clamp to release (264.5-.32T). He said this was because the points of contact of the corners of the aperture against the notches in the bar may move, releasing the tension between the fixed jaw and the moveable jaw (264.25-.37T). I interpolate, that Dr Casey observed that the clamps used by Mr Coulthurst were worn (262.26-.30T). If one clamp fails in this way the remaining clamp would be subject to a mechanical disadvantage of leverage which may cause the remaining F clamp to fail also (265.15-.37T). If both clamps fail and the cleats fall away there would be a tendency for the beam to swing out towards Mr Coulthurst because that was its rest position below the hitching point when it was moved beyond the post and steel column by the excavator before Mr Coulthurst pushed it back into its intended place. Dr Casey said "simple oscillatory motion says it will swing back twice that distance" (264.39T; 264.5-265.30T). I interpolate, if Mr Coulthurst's estimate is accurate, this would be a distance of about 200mm. Dr Casey also hypothesised that the pushing of the beam into position by Mr Coulthurst could have caused the slings to assume a slight angle promoting a tendency to rotate to the vertical as it was lowered imparting force to the mechanical pinch point on which the security of the Fclamps grip depended (259.28-.43T).
Dr Casey was asked to examine Exhibit 12 drawn from CB 226 which consists of two photographs reproduced by Mr Waddell of an apparent reconstruction of the clamping methodology adopted by Mr Coulthurst. Dr Casey pointed out that the cleats were not parallel, not perfectly horizontal, and neither was sitting at the same angle. These factors would promote movement in the temporary support arrangements if the beam rotated as it moved. This could promote failure of the F clamps of the type Dr Casey had been discussing (267.5-.40T; 260-261T). I interpolate that in evidence Mr Coulthurst identified Exhibit A as reconstructing the manner in which he affixed the temporary supports (31.5-32.5T). In that photograph, so far as one can tell, the cleats seemed to be in a horizontal plane and parallel, even if each clamp is not exactly in the same position. I should also note here that Dr Casey opined that the rotation of the beam could also be caused by the beam being lowered when the face of the beam was not being held vertically in the slings (260-262T).
In cross-examination, Dr Casey said that the two main possibilities explaining the movement of the beam were: the disengagement of the F clamps resulting in the release of the tension provided by the angle on the slings produced when Mr Coulthurst pushed the beam back into position, or the boom on the excavator "moved in towards the house, or the point of attachment moved in towards the house" (269.10-270.2T). He also accepted that the friction between the end of the steel beam and the steel column was enough to hold the beam in place before and while Mr Coulthurst went through the process of applying the lateral supports (270.15-.20T). Dr Casey also said that if the beam swung out further towards Mr Coulthurst than the distance he had earlier pushed it into position, it would suggest that the hitch point at the end of the tip of the boom "has moved towards Mr Coulthurst" (271.5T). Another possibility was that the downward movement of the dipper arm of the excavator unsettled "the whole arrangement" (271.20T), but: "If you accept that it came a lot more than the initial position that he had to push it back (from), then that would indicate to me that the hitch point of the slings has moved towards Mr Coulthurst" (271.38T). That can only happen if Mr Miles had either moved the dipper arm towards Mr Coulthurst or driven the excavator forward (271.50T). Dr Casey also said that if after Mr Coulthurst fell the beam swung back knocking over the timber post and dislodging its clamps that indicates, "that the end of the beam was lower than its original position" (273.45T). One possibility for that result was that "the hitch point was continuing to come down in the swinging process" (274.3T). Another possibility is if Mr Coulthurst, in self-preservation, I interpolate, pushed it or otherwise influenced its movement somehow (274.15T). If Mr McCaffrey's end came free when Mr Coulthurst's end swung out towards him "the force required to then move the beam is much, much less than if it stays fixed at Mr McCaffrey's end" (274.35T).
Both explanations required the application of force to the beam and lowering the beam may generate the necessary force to disengage the F clamps (274.50-275.10T).

Conclusions of primary fact

As I have said the principal factual issue relates to the cause of Mr Coulthurst's fall. I am satisfied on the balance of probabilities that Mr Coulthurst was knocked from the ladder by the steel beam when it swung out from the temporary lateral supports he had put in place during the final adjustment necessary to position it on the timber prop. This involved lowering the beam the very short distance of 10mm. Of course, the purpose of the temporary supports was to restrain the beam and hold it in position until it was welded to the steel columns by the steel fabricators. The cleats and clamps were not assembled to facilitate the beam's final adjustment.
I find that the beam swung out because Mr Miles in fact operated the levers controlling the lifting apparatus of the excavator to lower the beam into its intended position. Given his unawareness of the availability of the quick release mechanism for this purpose, lowering the beam required him to use the left lever to lower the dipper head. I address below the question of whether he also operated the right lever to pull back the boom in his "double movement" scenario. As in all things there may have been other, concurrent causes including conditions for which Mr Coulthurst was responsible as I will discuss for reasons explained below when considering the question of contributory negligence.
In arriving at these two findings of fact, I accept the evidence of Mr Coulthurst that he was in fact struck by the beam and knocked off his perch on the ladder. Although he tended to be a discursive, rather than direct, historian, I was impressed by the adamance of his evidence on this point. In assessing his evidence about this, I have borne in mind that it was obvious that Mr Coulthurst, when he gave evidence in 2019, had had plenty of time to ruminate on what happened. During that period he apparently worked more than once on his evidentiary statement which was, at least in part, produced by a process of "to-ing and fro-ing" between him and his solicitor (71.10-.49T; 105.39-.50T). But I did not think the evidence I have recounted at [26] and [32] above was the product of reconstruction or over-introspection, as sometimes occurs. I appreciate that there were a number of differences between his evidentiary statement and his evidence-in-chief. The same is true of Mr Miles. As I have remarked Mr Coulthurst's evidentiary statement, comprehensive as it appeared on its face did not contain the whole of his account.
In making my second finding I cannot accept Mr Miles's statement (Exhibit 11 [38]) that he was not moving the beam with the excavator immediately before or when Mr Coulthurst fell. The directness of his statement was watered down very considerably under cross-examination and reduced to a statement of belief that he was not operating the levers. His evidence at 185.45T recounted at [59] above is very close to a recantation of Exhibit 11 at [38]. I accept the admission relayed to Dr Casey by the defendants' solicitors in Exhibit J, that Mr Miles was using the levers of the excavator to lower the beam straight down when the beam swung out towards Mr Coulthurst. Given the solicitors expressed themselves by saying "the defendant instructs" this statement can be attributed directly to Mr Miles. And it was a statement made by Mr Miles sometime before 19 April 2018, when the solicitors wrote qualifying Dr Casey to give expert evidence. I should also say that defendants' counsel contended that I should find Mr Miles was lowering the beam, albeit in response to a signal from either Mr Coulthurst or Mr McCaffrey, when the steel beam swung out towards Mr Coulthurst (written submissions 5 March 2020, at [65]-[69]).
Although Mr Miles, from his position in the excavator cab, could not see precisely where in relation to the timber prop Mr Coulthurst's end of the steel beam was, he knew they were still in the process of moving the beam into position (190.5T; 190.20-.25T). He was aware that the slings remained taut and said, "If it's still hanging from the slings it wasn't … bedded down" (194.44T). Moreover, had it been bedded down, Mr Coulthurst would have moved to the middle of the beam in proximity to the slings for the purpose of removing them after the tension was slackened and he had not done so. He was still at his end.
I largely accept the evidence of Dr Casey. In the end, each of Dr Casey's two preferred hypotheses involved an initiation of movement of the beam by the application of force to it by operating the excavator including to lower the beam. The alternative operation, moving the excavator forward in response to a signal in that regard is not supported by the evidence of any witness or indeed the apparent logic of events. Lowering the beam is the most likely inference as to the source of the force imparted as necessary to initiate the short chain of events resulting in Mr Coulthurst's injury.
In rejecting Mr Miles's affirmative statement that he was not operating the excavator's lifting apparatus, and accepting his admission to the contrary in Exhibit J, I should not be taken as stating that I have formed the view that Mr Miles gave deliberately false evidence. Nor was such a proposition put to him. It was put that I should reject Exhibit 11 at [38] (plaintiff's written submissions, p.3 at [9]). It seems obvious to me that Mr Miles would prefer not to have to regard his operation of the excavator as responsible in any way for Mr Coulthurst's injuries, whether or not this involves the attribution of legal responsibility to him. This is not a state of mind unfamiliar to courts dealing with cases of civil wrong. I do not regard Mr Miles as a dishonest witness.
I also find that Mr Miles lowered the beam too far and it was this "over-operation", as I would put it, of the dipper head that generated the force necessary to cause the F clamps to give way, releasing the lateral supports and permitting the beam to swing out towards Mr Coulthurst, more or less in the sequence described by Dr Casey. To break this up into what seem to be its constituent parts, even if that process is a little artificial because of the unavoidable imponderables, force was imparted to the beam by activation of downward movement of the beam through operation of the left-hand lever to move the dipper head. Contrary to Dr Casey's hypothesis, I accept the alignment of the beam was then in a vertical plane due to the application of the cleats and clamps as stated by Mr Coulthurst, supported in this as he was by Mr Waddell. The lateral movement toward Mr Coulthurst occurred: in part due to the tension between the hitch point and the beam introduced by him pushing the beam back into alignment with the prop initially; in part, by a degree of forward arcing movement of the dipper head as the beam was lowered as depicted in Dr Casey's Figure 3 (see [47] above); and in part by the beam moving off and below the line of the prop as the beam's downward momentum continued beyond the level of the top of the prop because of the "over operation" of the dipper head lever. For reasons I elaborate below, of these the pendulum response to Mr Coulthurst's push was the least significant for the reasons given in the next paragraph. As a result, one of the F clamps holding the cleats failed because of the force applied to the pinch point on the corners of the aperture over the bar. And the second F clamp failed through leverage of the cleat in response to the force applied by the continuing lateral movement of the steel beam. It is not possible to say which of the clamps failed first, but in my view logic suggests it was probably the clamp adjacent to the sides of the beam. The combined effect of all of these factors permitted, indeed caused, the steel beam to swing out from its intended position. This chain of events occurred "in an instant". Although somewhat complex these interdependent events are supported by the evidence I have summarised above.
In my judgment, on the probabilities, the beam, when it swung, moved beyond the point of oscillatory motion described by Dr Casey. This is for five reasons. First, I accept Mr Coulthurst's evidence (at 137.20T; at [35] above) that he pushed the beam back for a distance of 100mm only. The point of oscillatory motion is simply dictated by the degree of tension imparted by Mr Coulthurst's act of pushing the steel beam back into line with the steel column and the timber prop. That in turn is a function of the distance over which it was pushed. Dr Casey defined the point of oscillating motion as twice that distance, here 200mm. Secondly, I am satisfied that after he had applied the cleats and clamps Mr Coulthurst moved back, I infer, out of what he regarded as harm's way to his original position, about an arm's length from the beam. This is a distance of about 600mm which was beyond the extent of oscillatory motion. Not that Mr Coulthurst would have had any regard to those engineering concepts, or, probably, even knowledge of them. Thirdly, it has to be recalled that the beam was pushed back because the excavator had travelled beyond the line of the steel column and timber prop. That is to say the hitch point was driven beyond the line of those items. When Mr Coulthurst initiated his push, the beam was hanging inert by the slings from the hitch point which was the beam's point of rest. The action to which Newton's third law applied, according to Dr Casey, was Mr Coulthurst's push. Fourthly, from Mr Coulthurst's description of what happened, I am satisfied that when the lateral supports failed the steel beam swung out towards him with greater force than he had imparted earlier by pushing the beam. On the facts I have accepted the beam knocked Mr Coulthurst off the ladder and Mr Coulthurst was clearly more than 200mm from the timber prop. I do not accept that a movement of 200mm would have been sufficient to startle him, causing him to lose his balance. Fifthly, it is evident that the restraint or resistance provided by Mr Coulthurst's arrangement of cleats and clamps in lateral support of the beam were adequate to hold it in place notwithstanding the tension provided by the angle between the hitch point and the beam until the additional force introduced by Mr Miles's activation of movement in the dipper head. I am of the view that the greater force necessary to overcome the restraint of the lateral supports was imparted by Mr Miles lowering the dipper head more than was necessary to seat the beam on the timber prop. Importantly, for the reasons I have explained the downward movement was accompanied by a degree of lateral movement towards Mr Coulthurst. This lateral component of the beam's movement explains the degree of movement accounts for the force applied to the pinch point on the F clamp holding the cleats against the side of the beam which probably caused it to fail.
I am also satisfied that the beam came at Mr Coulthurst on a horizontal plane below 2900mm above the floor of the residence under construction. To my mind this is established on the probabilities by the circumstance that when it swung back after knocking him from the ladder, the steel beam dislodged the timber prop.
I think it probable that Mr McCaffrey's end of the beam moved off the steel plate. I draw the inference available from Mr Miles's evidence referred to at [54] and [61] above. I also accept Dr Casey's evidence that when the whole weight of the beam was suspended from the slings, and swinging, its trajectory could be altered by the application of less force than if Mr McCaffrey's end remained on the steel plate. Even so, I accept the accident happened suddenly, as I have said, and that Mr Coulthurst had no time to react in a purposeful way. I am persuaded that he when was struck he had no time to attempt to fend off the steel beam.
I am satisfied that Mr Coulthurst applied the cleats and F clamps to the temporary lateral supports in the manner depicted in his reconstruction in Exhibit A. I make this finding in preference to a finding that the lateral support was assembled as depicted in Exhibit 12 (CB 226), to the extent to which there is a material difference between them, as there may well be as explained by Dr Casey. Mr Coulthurst gave sworn testimony that the temporary lateral supports were assembled as depicted in Exhibit A and he was not challenged about that matter in cross-examination.
I accept that the F clamps used by Mr Coulthurst exhibited a degree of work wear; in particular, that the notches on the bar and the corners of the aperture were not as "sharp" (Dr Casey, 262.20T) as when new. But I did not understand Dr Casey to say that the clamps were unserviceable. And Mr Waddell was not prepared to say that the F clamps were faulty. I find that although worn Mr Coulthurst's F clamps utilised by him on the day were serviceable and of reasonable fitness for the purpose at hand.
As I have said, the thrust of Dr Casey's evidence is, whether the beam swung out because the clamps failed or because of the arcing movement of the beam as a function of the downward movement of the dipper head, the swinging process had to be initiated by another or additional force. As Mr Waddell said see [67] above, "the beam which knocked Mr Coulthurst off his ladder was acted on by an external force". I am satisfied on the balance of probabilities that failure of the F clamps because of undue wear and tear was not the cause of the beam swinging out. Rather, I am persuaded that the deliberate movement of the beam itself by Mr Miles, arcing downward and beyond the point required to seat it on the timber prop, overcame the resistance provided by the cleats and clamps. I regard it as highly relevant that Mr Coulthurst had used the F clamps in this type of operation very frequently over the years, developing techniques for the task by which he was able to overcome the obvious difficulties.
I have decided that the downward movement executed by Mr Miles involved an arcing movement of the kind illustrated in Dr Casey's figure 3 by the red triangle (see [47]). From figure 4 (see [47] above), one can readily see that at the height required to seat the beam on the timber prop of 3750 millimetres, rather than the maximum of 3957.565mm illustrated, the boom must have been fully "pulled back", even if the dipper arm would have been about 200mm, or about 8 ins, lower and slightly more towards the horizontal than depicted in the computer generated illustration (figure 3). The point is, at that height, accepting the lift was within the reach of the excavator, it is not apparent that there would have been any capacity to pull the boom further back in Mr Miles "double movement". From figure 4, it appears that there was not. The lowering of the beam required to finally seat it on the timber prop was very small, but even so, it was sufficient to cause a degree of forward, as well as downward, movement. The effect would have been accentuated by the consideration, as I have found, that Mr Miles lowered the beam too much, more than was required to seat it on the timber prop.
Despite his experience there were obvious gaps in Mr Miles knowledge. Of particular relevance was his unawareness of the availability of the quick release mechanism as a means of lowering the beam vertically, eliminating the component of forward motion. The downward movement of only 10mm doubtless required a deft touch. Not only was the required movement minimal but it was at the same time necessary to impart sufficient force to overcome the friction between the end of the beam and the steel column. The apparent logic of events suggests that a non-professional plant operator might readily have erred in executing the necessary adjustment. In absolute terms 600 hours may sound like long experience. But there was no evidence that Mr Miles had received formal training. My Impression was he was self-taught, learning through use. If one assumes, these days, that a 35 hour working week is normal, 600 hours translates into a little over 17 weeks. In Mr Miles case this doubtless was stretched over a longer period not specified in the evidence. I accept he was not a beginner, but one could not say he had vast experience.
For these reasons I am satisfied that the manner of Mr Miles management of the excavator caused the beam to overcome its lateral restraint and swing out knocking Mr Coulthurst from his ladder before swinging back and taking out the timber prop.

Duty of care

As I have said (see [14]) above), Mr Doherty submits that a plant operator owes a general duty to exercise reasonable care in operation of the plant to avoid unnecessary risk of personal injury to other persons engaged in the work within the sphere of operations arising out of the movements of the machine or its load. Mr Greenwood does not dispute that in his capacity as a plant operator vis a vis the other persons involved in the work, here Mr Coulthurst and Mr McCaffrey, Mr Miles owed such a duty of care.
Mr Greenwood disputes that there is any other aspect of the relationship between the parties which gives rise to a duty of care. He submits that the relationship of occupier and entrant is irrelevant to the question in the circumstances of this case and the relationship between Mr Miles and Mr Coulthurst as an owner-builder on the one hand, and contractor on the other, does not of itself give rise to a duty of care.
I agree that in his capacity as a plant operator, Mr Miles owed Mr Coulthurst (and Mr McCaffrey for that matter) a duty to exercise reasonable care in the operation of the excavator to avoid unnecessary risks of personal injury. One need not go beyond Lord Atkin's speech in Donoghue v Stevenson [1932] AC 562 at 580 where his Lordship said: You must take reasonable care to avoid acts or omissions which you can reasonably foresee would be likely to injure … persons who are so closely and directly affected by [the] act that [you] ought reasonably to have them in contemplation as being so affected when [you are] directing [your] mind to the acts or omissions which are called in question.
Given that the focus of Mr Doherty's argument has been on Mr Miles "casual negligence" in operation of the excavator it is not necessary to go beyond that categorisation.
Were I wrong in that conclusion, I would have been of the view that the risk of injury which materialised in the present case was beyond the scope of the duty of occupier and entrant. One of course accepts that the content of the occupier's duty may extend beyond responsibility for the condition of the premises to considerations relevant to the reasonable safety of activities or operations carried out on them: Thompson v Woolworths (Qld) Pty Ltd (2005) 221 CLR 234; [2005] HCA 19. However, it is quite clear that neither Mr Miles nor Ballyshaw assumed any responsibility for organising the activity of constructing the portal; nor did they undertake to devise and implement the system for constructing the portal, and in particular for lifting the steel beam into position. It is relevant to consider that although working as a sub-contracting tradesman selling his skill and labour at an hourly rate, part of Mr Coulthurst's skill which he brought to bear in the performance of his work was his experience and expertise in residential building work. To that extent, focusing only the task at hand, Mr Coulthurst liaised with the engineers and the steel fabricators in relation to the design of these steel structural components and the most efficient method of affixing those components to the residence under construction. That is not to say that he was responsible in any sense for design from an engineering perspective or the intricacies of steel fabrication. But he knew how things fitted together and as part of the services he provided he deployed that skill on behalf of the defendants. It's not denied, and indeed it is incontrovertible, that he had the necessary skill and experience to devise and implement the system of work for this task and he in fact did so. It seems clear that there was some discussion between Mr Coulthurst and Mr Miles about the suitability of the excavator as a lifting device on this particular task. The conversation about hiring a Franna crane was brief and may have related to potential problems with delivery of the structural steel components. Mr Miles was confident that the excavator could do the job just as it been used to lift other heavy structural components on site. A trial run was carried out to check its suitability. There is no longer any issue about whether a crane should have been used for the lift. As I have said, the emphasis in Mr Coulthurst's case is on the manner of operation of the excavator by Mr Miles not its suitability as a means of lifting the steel beam into place.
For similar reasons, I am of the view that the relationship of owner builder and subcontractor is not germane in present case. As in Kolodziejczyk v Grandview Pty Ltd [2002] NSWCA 267 Mr Coulthurst was an independent contractor with long experience in the work he was engaged to perform when injured. He, and Mr McCaffrey for that matter, "determined what work he did, when, in what order, and how, without instructions from the defendant": Kolodziejczyk at [49]. If any duty arose out of the relationship of owner builder on the one hand, and independent contractor on the other, it was of the kind explained by Brennan J (as the Chief Justice then was) in Stevens v Brodribb Sawmilling Co. Pty Ltd (1986) 160 CLR 16; [1986] HCA 1 at 47 - 48. Such a duty involves the use of reasonable care in organising the relevant work activity. However, "it does not import a duty to retain control of working systems if it is reasonable to engage the services of independent contractors who are competent themselves to control their system of work without supervision by the entrepreneur": Stevens at 47. This is that case. There is nothing in the circumstances which made it necessary for the owner builder to exercise supervisory power or to prescribe the respective areas of responsibility of independent contractors. Here, Mr Coulthurst and Mr McCaffrey, both experienced carpenter/builders, were working together as a team. There was no need for any supervision from Mr Miles. No duty of care of this kind arose: see also Leighton Contractors Pty Ltd v Fox (2009) 240 CLR 1; [2009] HCA 35.
So far as Mr Miles's duty as a plant operator is concerned, I have made reference to his lack of qualifications and what might be referred to as his relative lack of experience compared to a professional operator. These considerations do not in any way alter, attenuate or reduce the standard of care required to discharge his duty to whomsoever it was owed: Imbree v McNeilly (2008) 236 CLR 510; [2008] HCA 40. The standard is that of the reasonable plant operator. Even knowledge of inexperience or lack of qualifications on the part of the person to whom the duty is owed is not "a sufficient basis upon which to found a different standard of care": Imbree at [55]. Gummow, Hayne and Kiefel JJ said at [58]: … to describe the relevant comparator as "unqualified" points only to the absence of approved demonstration of adequate driving competence. Demonstration of relevant ability is beside the point. What is at issue is the definition of a standard of reasonable care, not any external recognition of attaining an ability to drive in accordance with that standard.
I repeat again that Mr Miles owed Mr Coulthurst (and Mr McCaffrey for that matter), a duty to exercise reasonable care in the operation of the excavator to avoid unnecessary risk of personal injury arising out of the movements of the machine or its load while the latter was attached. The standard of care expected by the law of Mr Miles was that of a reasonable plant operator in the circumstances.

Identification of the risk of injury

Having identified the duty, its content and the standard of care due in accordance with the common law, all questions of negligence must be determined in accordance with the provisions of Part 1A Civil Liability Act 2002 (NSW). Section 5B establishes the general principles to be applied to decide whether a person was negligent in failing to take precautions against a risk of harm. However, the starting point of the inquiry required by s 5B, as with the previous common law, is to accurately identify the actual risk of injury against which precautions are said to be due for the purpose of elucidating the true source of potential injury.
In Coles Supermarkets Australia Pty Ltd v Bridge [2018] NSWCA 183 Leeming and Payne JJA said at [20] - [22]: "The provisions of the Civil Liability Act require the analysis to start with a risk of harm: see Uniting Church in Australia Property Trust (NSW) v Miller; Miller v Lithgow City Council (2015) 91 NSWLR 752; [2015] NSWCA 320 at [104]-[107]. It seems plain that there is no single correct "risk of harm", and that there are leeways of choice between formulations that are more or less general or specific: Uniting Church in Australia Property Trust (NSW) v Miller at [119]. However, it is "only through the correct identification of the risk that one can assess what a reasonable response to that risk would be": Roads and Traffic Authority of NSW v Dederer (2007) 234 CLR 330; [2007] HCA 42 at [59] (Gummow J, with whom Heydon J agreed). As Basten JA said in Garzo v Liverpool/Campbelltown Christian School [2012] NSWCA 151 at [7], "the risk must be that which materialised in the case of the injured person seeking to claim in negligence". Meagher JA said at [22]: "To address the questions and considerations in s 5B, it is necessary to formulate a plaintiff's claim in a way which takes account of the precautions which it is alleged should have been taken and identifies the risk or risks of harm which the plaintiff alleges eventuated and to which those precautions should have been directed." Both formulations use hindsight, in the sense that they insist that the legal analysis be framed so as to encompass the risk which is claimed to have materialised and caused the damage of which the plaintiff complains. That seems to be entirely unexceptional. It has been said that the formulation of risk of harm should identify the "true source of potential injury" (Roads and Traffic Authority of NSW v Dederer (2007) 234 CLR 330; [2007] HCA 42 at [60]) and the "general causal mechanism of the injury sustained" (Perisher Blue Pty Ltd v Nair-Smith (2015) 90 NSWLR 1; [2015] NSWCA 90 at [98]); see also Avopiling Pty Ltd v Bosevski; Avopiling Pty Ltd v The Workers Compensation Nominal Insurer [2018] NSWCA 146 at [43]. In Erickson v Bagley [2015] VSCA 220 at [33] and in Southern Colour (Vic) Pty Ltd v Parr [2017] VSCA 310 at [55], the Victorian Court of Appeal said, "Necessarily, the risk must be defined taking into account the particular harm that materialised, and the circumstances in which that harm occurred." What is to be avoided is an unduly narrow formulation of risk of harm which then distorts the reasoning, because, for example, it obscures the true source of potential injury (as noted in Dederer at [60]) or because it too narrowly focusses on the particular hazard which caused the injury (as noted in Port Macquarie Hastings Council v Mooney [2014] NSWCA 156; [2014] Aust Torts Rep 82-172 at [67]), or because it fails to capture part of the plaintiff's case (as in Garzo)."
Both parties addressed this issue. Mr Doherty submitted that "the true source of potential injury was [Mr Coulthurst] being struck by a 260kg steel beam if it dropped or swung out of control": written submissions, p.7 at [25]; see Roads & Traffic Authority of New South Wales v Dederer (2007) 234 CLR 330; [2007] HCA 42 at 351.
Mr Greenwood criticised this formulation as impermissibly narrow and viewed through the lens of hindsight. He submitted that the risk of harm was that "if the system of work was not devised and implemented with due care and skill the plaintiff may suffer injury and damage".
In Coles v Bridges, Leeming and Payne JJA, as the extract above makes clear (at [22]), regarded it as "entirely unexceptional" that hindsight was brought to bear in the process of accurately assessing the risk of injury involved. Their Honours said unduly narrow formulations of the risk of harm are to be avoided. However, it is clear that the legal analysis is to encompass the risk which is claimed to have materialised "in a way which takes account of the precautions which it is alleged should have been taken": Garzo v Liverpool/Campbelltown Christian School [2012] NSWCA 151 at [22] (Meagher JA) (see Coles v Bridges at [21]). Mr Doherty submitted (written submissions, p.7 at [27]) the defendant "was in control of the excavator and its load. Either by operating the joysticks or by moving the excavator forward, the defendant caused the beam to suddenly swing out of control striking the plaintiff …".
In my judgment Mr Doherty's formulation is closer to the mark. For reasons I will explain when dealing with contributory negligence I would not regard this as a "system of work case". Moreover, the question concerns whether legal responsibility should be attributed to Mr Miles or Ballyshaw, neither of which were involved in instituting and maintaining the system. The question relates to whether in playing his part in the system, Mr Miles was negligent. His part in the system was the control and operation of the excavator as a means of lifting the steel beam into place. I accept Mr Doherty's initial formulation which is that the relevant risk of harm against which precautions needed to be taken was the risk of the other participants in the work, Mr Coulthurst and Mr McCaffrey, being struck by the steel beam and thereby suffering personal injury.

The question of breach - Did Mr Miles breach his duty of care?

Mr Coulthurst's case had been expressed in various ways in the pleadings, but at the end of the hearing it relate to questions about the management and control of the excavator of which Mr Miles was the operator. Mr Doherty argued (written submissions, p.5 at [14]) that the swinging of the steel beam could only have been caused by one of two things: either the defendant operating the joy sticks in such a way "as to jerk the beam out of its position" or Mr Miles "driving the entire excavator forward thereby jerking the beam out of position". I have rejected the second alternative of the excavator moving forward as a matter of fact (see [89]) above. The same concept was expressed absent "jerking" at written submissions, p.7 at [27], where the case was put that "by operating the joysticks or by moving the excavator forward, the defendant caused the beam to suddenly swing out of control striking the plaintiff" as I have already said.
Mr Greenwood submitted that the "jerking out of position case" was not open to Mr Coulthurst. However, I am of a different view. The pleading at sub-paragraphs 33(g) and 44(d) of the Amended Statement of Claim filed on 18 January 2019 ("ASOC") are apposite. The former avers that a reasonable person in the position of the first defendant would have taken precautions including: To inform himself of the intricacies of the working of the arm of the excavator, and in particular, when attempted to lower the arm of the excavator, the excavator arm would simultaneously move in a downwards direction and a forward direction. The latter avers that Mr Miles was negligent in the method of operation of the excavator by: Operating the excavator in such a manner as to cause the beam to become dislodged and cause injury to the plaintiff, namely causing the arm of the excavator to simultaneously move forwards and downwards meaning the prospects of dislodging the beam became very likely.
I would regard the language of "jerking out of position" in written submissions as no more than a permissible rhetorical flourish. That expression, it seems to me, adequately accommodates the matters I have set out above.
Moreover that allegation is in conformity with the findings of fact I have made at [85] and [100] above for the reasons given under the heading "Conclusions of primary fact". I will not rehearse that material here. The question remains did the acts and omissions of Mr Miles to which I have referred constitute negligence. This is a question of course which must be answered by applying the provisions of Part 1A of the Civil Liability Act and in particular ss 5B and 5C.
Before turning to the statutory provisions, I wish to acknowledge that Mr Greenwood submitted that what happened to Mr Coulthurst was just an accident in an intricate process in which three conscientious persons were trying their best to achieve a safe outcome; alternatively, as I have already stated, if there was fault it was on the part of Mr Coulthurst who was responsible for devising and implementing the system of performing the work; and in that regard Mr Miles did no more than operate the excavator in accordance with "instructions" he received from Mr Coulthurst.
In my judgment the incident was not an inevitable accident as it could have been avoided by the exercise of reasonable care on the part of those involved including Mr Miles. So much at least must be taken as having been demonstrated by the events of the following day, subject of course, to the s 5C considerations. As I have already said, I think it appropriate to discuss whether there was a want of reasonable care on the part of Mr Coulthurst when dealing with contributory negligence.
Concerning whether Mr Coulthurst was "instructing" Mr Miles in the operation of the excavator, one must not confuse the semantics. Mr Coulthurst was signalling Mr Miles either directly or through Mr McCaffrey as to the direction in which the beam had to be moved to be placed into position. He was in no sense instructing Mr Miles in the proper operation of the excavator. Mr Miles at all times was the person controlling the movements of the excavator. In the language of the pleader normally employed in this area, at all material times it was under his management and control. Mr Coulthurst was not directing Mr Miles as to how to manipulate the controls of the lifting apparatus to achieve any particular movement of any of the three parts of that apparatus so the desired outcome would be achieved. That was Mr Miles's job. Mr Coulthurst was merely indicating the direction in which the beam, not the components of the lifting apparatus, had to move to be placed in position on its temporary support.
Returning then to the question of Mr Miles's negligence. In terms of s 5B(1)(a) and (b) there can be no doubt that the risk of personal injury to workers engaged in the process of lifting and positioning the beam was both foreseeable and not insignificant and Mr Greenwood did not argue otherwise. The work involved the operation of a significant piece of machinery to lift a long, heavy, rigid object into position to a height of approximately 3.7m in an operation which required other workers to be in proximity to the beam to guide or direct the excavator operator as to the necessary direction of travel of the beam into its intended position. It was certainly foreseeable that if reasonable care were not exercised one of the workers could be struck by the beam suffering serious personal injury. That risk was not insignificant in as much as the chance of it materialising was real and the potential if it did materialise for serious injury was high.
The next question is whether in the circumstances a reasonable person in Mr Miles's position would have taken the necessary precautions. The question relates to a reasonable excavator operator in Mr Miles's position. I bear in mind that this question has to be looked at without the benefit of hindsight, entirely prospectively, and as though the injury to Mr Coulthurst had not happened: Vary v Wyong Shire Council (2005) 223 CLR 422; [2005] HCA 62 at [126] - [128] (Hayne J); Neindorf v Junkovic (2005) 80 ALJR 341; [2005] HCA 75 at [97] (Hayne J).
I appreciate that I have also made reference to Mr Miles lack of formal training and qualifications and relative lack of experience. However, I am well aware the question relates to the reasonable plant operator in his position and in this regard training, qualifications and experience are not determinative. The question relates more to a level of competence: Leask Timber & Hardware Pty Ltd v Thorne (1961) 106 CLR 33; [1961] HCA 73; (1961) ACA 73 at 45 (Kitto J). Training, qualification and experience of course may inform the competence of a reasonable plant operator but they are not synonymous with it. The standard is that of reasonable care, not a particular level of qualification. I also direct myself given the nature of the evidence led in the case, that the requisite standard is not the standard of a mechanical engineer.
In my judgment a reasonable plant operator in Mr Miles's position required to lower a steel beam a very short distance onto a timber prop, which beam had already been lifted to a height where the boom was fully pulled back, and the dipper arm was already well above the horizontal, and the necessary movement was also required to overcome the friction between the end of the beam and the steel column, which was holding the beam above its resting place on top of the timber prop, would have appreciated that reasonable care required an intricate movement of some deftness in a wholly vertical plane. The reasonable plant operator would also have appreciated that the beam was under tension because Mr Coulthurst had pushed it back a short distance into position above the prop. This factor would have increased the deftness required in lowering the beam. In my opinion, on the balance of probabilities, a reasonable plant operator would have decided to execute the manoeuvre by use of the quick release mechanism to eliminate the arcing motion of the elevated dipper arm in favour of a vertical downward movement. In my judgment reasonable care required that approach and a reasonable plant operator in Mr Miles's position would have taken that precaution.
In coming to this conclusion, I have had regard to the s 5B(2)(a) - (d) factors. In my judgment there was a significant degree of probability that harm would occur if care were not taken because of the proximity of Mr Coulthurst, and Mr McCaffrey to the beam during these operations. Given that Mr Coulthurst and Mr McCaffrey were working in a vulnerable, elevated position on ladders from which they could be dislodged if the beam swung out of position, it's quite likely that significant personal injury could be suffered. There was no burden in taking reasonable care in the operation of the controls of the lifting apparatus of the excavator. And the social utility of the work on which Mr Miles, Mr Coulthurst and Mr McCaffrey were engaged did not justify courting the risk. In my judgment Mr Miles breached his duty of care by failing to take the precaution of utilising the quick release mechanism to eliminate the downward arcing trajectory of the operation of the dipper arm to obviate the unnecessary risk of personal injury.
I am conscious that Mr Waddell suggested that the same result could be achieved by reversing the excavator while lowering the dipper head. However given the deftness of the required operation a single movement is to be preferred. Reversing at that stage may have occasioned the materialisation of risk of injury by other mechanisms.

Liability of Ballyshaw

It is to be borne in mind that Mr Miles's company conducted the horticultural and grazing enterprises carried out on the land that was owned personally by Mr Miles. It also paid the construction costs but Mr Miles was the owner/builder. In a somewhat curious pleading (Defence to Amended Statement of Claim [2] CB 69-70) "the Defendants … say that the Second Defendant acquired the legal title to the House following its completion"; ordinarily one would have thought that legal title to a house built on the landowners land would vest in the landowner by operation of law.
Although the evidence is that Ballyshaw carried on the primary production enterprises on the property, there is no evidence that it occupied the construction site or otherwise had control over it. There is no evidence that Mr Coulthurst and Ballyshaw were in a relationship of entrant and occupier.
The evidence is that Mr Miles was the owner/builder, but Ballyshaw paid the cost of construction, as I have said. But there was nothing in the evidence to suggest that Ballyshaw was the de facto builder responsible for the construction. There is nothing to suggest that Ballyshaw owed Mr Coulthurst the duty owed by an entrepreneur to contractors working on the project.
Mr Greenwood submitted that from the plaintiff's written submissions it appeared that no claim was pressed against Ballyshaw (written submissions, p.11 at [83]) and I agree that the company is not mentioned in the written argument. Nor did Mr Doherty make any separate case against Ballyshaw in oral argument. As I have been emphasising, the focus of Mr Coulthurst's case was on Mr Miles's control and management of Ballyshaw's excavator and reliance was placed upon his acts or omissions in that regard to make a case in negligence.
A consideration of the averments in the ASOC demonstrates a focus upon the liability of Mr Miles. Various allegations are advanced separately against Ballyshaw from [58] to [68] of the ASOC. These allegations embrace occupier's liability, liability as owner of the excavator and as an occupier with responsibility for the construction work. Reliance is placed upon the particulars of negligence pleaded against Mr Miles in his capacity as an owner builder in [43] of the ASOC. For the reasons I have already addressed, none of these cases have been made out and in truth, it does appear that no case is pressed against Ballyshaw in those respects.
A case is also pleaded against Ballyshaw for a breach of statutory duty said to arise under various provisions of the Work Health and Safety Regulation 2011 (NSW). Reliance is placed upon the pleading of the same matters against Mr Miles by incorporation. However, no case of breach of statutory duty was pressed or made out against Mr Miles in written submissions or addresses, and these matters should be put to one side.
By [62] of the ASOC, Mr Coulthurst relies upon the vicarious liability of Ballyshaw for the negligent acts of Mr Miles in the operation of the excavator. In [5] of the ASOC, Mr Coulthurst avers that Mr Miles was "acting either in his capacity as the owner of the premises or in his capacity as the servant or agent or partner of, or joint-venturer with" Ballyshaw. This averment was not admitted and therefore may be taken as having been traversed. It seems to have been common ground that Mr Miles was a director and shareholder of Ballyshaw, but there is no evidence that he was an employee of the company or that when operating the excavator on 6 April 2016, he was in the course of any such employment. There is certainly no evidence that he was an agent, properly so called, a partner or a joint-venturer with Ballyshaw in the construction of the home and the operations being carried out on 6 April 2016. These considerations would put an end to the case of vicarious liability on conventional grounds: Sweeney v Boylan Nominees Pty Ltd (2006) 226 CLR 161; [2006] HCA 19.
I accept that Mr Greenwood is correct and that no claim is pressed by Mr Coulthurst against Ballyshaw. Notwithstanding the pleadings, as his case was refined by the trial process, Mr Coulthurst did not present any separate or independent case against Ballyshaw and he has not shown that it is vicariously liable for the negligence of Mr Miles.

Causation

The questions of causation are governed by the provisions of s 5D and 5E of the Civil Liability Act. By dint of s 5E the plaintiff always bears the onus of proving on the balance of probabilities any fact relevant to the issue of causation.
The duty of care owed by the operator of an excavator is akin to that owed by the driver of a motor vehicle to other road users and therefore falls into an established category of duty recognised by the law of negligence. Therefore the only real causation question that arises for determination is that posed by s 5D(1)(a) Civil Liability Act which is whether Mr Miles's negligence was a necessary condition of the occurrence of the personal injury suffered by Mr Coulthurst. No question arises as to the scope of Mr Miles's liability: Wallace v Kam (2013) 250 CLR 375; [2013] HCA 19 at [21] - [24].
As I have said Mr Greenwood's case was that the cause of Mr Coulthurst's accident was the inadequacy of the system of work for which he was responsible. Accordingly, it was submitted, causation has not been established.
It's not necessary for a plaintiff to prove that a defendant's negligence was the sole cause of the occurrence of his or her harm. It is sufficient that that negligence is a necessary condition of the occurrence of the harm. The law of torts and s 5B readily accommodate the phenomenon of concurrent causes: Grant v Sun Shipping Co. Ltd [1948] AC 549 at 563; Bennett v Minister of Community Welfare (1992) 176 CLR 408; [1992] HCA 27 at 429.
On the findings of fact that I have made, there can be no serious question that Mr Miles's acts and omissions in the operation of the excavator in his attempt to lower the steel beam onto the timber prop were necessary conditions to the occurrence of Mr Coulthurst's serious personal injury, and I so find on the balance of probabilities.

Contributory negligence

Mr Greenwood argues that if a finding of negligence is made against Mr Miles, a finding should also be made that the plaintiff was contributorily negligent by failing to take reasonable care for his own safety. The acts and omissions relied upon as constituting contributory negligence are as follows: 1. Mr Coulthurst was "responsible for the design of the fixing of the beam to the column" and did not include steel plates welded to the column in which the steel beam could have sat (defendant's written submissions, p.18 at [132]; 19.47-20.1T), I interpolate, this suggestion was rather like the arrangement of Mr McCaffrey's "pocket" (159.15T). Mr Coulthurst agreed such an arrangement could have been fabricated (150.1-.5T); 2. When the steel beam travelled beyond the prop and column, Mr Coulthurst should have directed the excavator to move back rather than pushing the beam and thereby imposing tension on the slings (defendant's written submissions, p.18 at [133]); 3. He should have "ensured that the beam was seated on a suitable support, stable or not under tension" before approaching it (defendant's written submissions, p.18 at [133]). He should have stood well back out of harm's way until he was satisfied the beam could not move laterally; 4. Effectively, he should have adopted the system that Mr McCaffrey put in place the following day.
Mr Coulthurst gave the following additional evidence in cross examination about some of these matters (149.50-151.20T): Q. Now, what I want to suggest to you is that there are a number of different ways in which this beam could have connected to these columns that would have avoided what occurred. The most obvious one is that there could have been steel plates welded to the columns that the beam just sat inside, couldn't there? A. Correct. ….. Q. Did you speak to the engineer about the fittings that could be put on the column to ensure that the beam sat directly onto a steel plate? A. No, they come up with the design on that, but it might have just been modified, how it actually was going to work. Q. That's certainly something that would have worked, would it not? A. For my end? Q. Yes. A. It could have, it could have, but I think they wanted flexibility in the height of it, in case it had to come down if, if they weren't exactly level. So it was decided, with the engineer, to change it to a site weld, to put a temporary support in there and do a site weld. Q. And that was a discussion that you had with the engineer, was it? A. Correct, yeah. Q. So was it in fact you that suggested not having a plate on that column so that you could then vary it, depending on the construction that was undertaken? A. It might have been my suggestion or it might have been - but we had, the plate had to go, so it could have been my suggestion or it possibly could have been the engineer's suggestion. Q. Another way that this could have developed was a different system being used to install the beam, and can I suggest to you that what could have been done was that you could have in fact placed supports for the beam underneath the beam and on either side of the beam, and then had the beam suspended with nobody needing to be standing on a ladder right beside it? A. To have supports - you could probably come up with a heap of different ways that - to do this, in hindsight. I don't know whether that's going to necessarily be better or provide less risk, but there certainly would have been different ways to do things, as there are in the building industry; heaps of different ways to do it. …. Q. Well, you didn't consider those different possibilities, other than the one that you used, which was merely to put a 45 by 90 post and then go up the ladder and try and support it on either side? A. We do that a lot, just put temporary supports in underneath, you know, garage beams and the - lot of things in the building industry, in the construction stage, put temporary supports in such as these, and then wait until the actual construction - it might be brickwork column going up or a bigger post going in, whatever the situation may be. It happens, happens quite frequently. So I had no hesitation thinking that was going to be a satisfactory way of doing it.
Apportionment for contributory negligence is governed by the provisions of s 9 Law Reform (Miscellaneous Provisions) Act 1965 (NSW); and ss 5R and 5S Civil Liability Act.
Importantly s 5R(1) is in the following terms: (1) The principles that are applicable in determining whether a person has been negligent also apply in determining whether the person who suffered harm has been contributorily negligent in failing to take precautions against the risk of that harm. It should be borne in mind that s 9 of the 1965 Act applies where a person suffers damage as a result partly of his or her own wrong and partly of the wrong of any other person. Before a person's damages are reduced for contributory negligence, it is necessary for the defendant, upon whom the onus lies, to prove that the plaintiff's contributory negligence is a cause of the plaintiff's loss.
Section 5S Civil Liability Act makes clear that a plaintiff's contributory negligence can, in an appropriate case, operate to defeat the whole claim. It's not submitted on behalf of the defendant that this is such an appropriate case.
Given the terms of s 5R, ss 5B and 5C are relevant principles applicable to contributory negligence, provided it is borne in mind that the question is whether Mr Coulthurst has departed from the duty to take reasonable care for his own safety: T and X Company Pty Ltd v Chivas [2014] NSWCA 235 at [4].
I am not satisfied that a reasonable person in Mr Coulthurst's position as a carpenter/builder would have exercised reasonable care for his own safety by insisting that the design for the steel structure of the portal included steel plates at his western end in which the steel beam could sit. As he said himself (Exhibit G; Annexure A at [32]; see [21] above) he "was not responsible for finalising the design or for having any input into the design other than for checking measurements and points for attachment". Moreover, as I have said, he is a carpenter/builder not a structural engineer. He discussed the matter with the engineers and the engineers "wanted flexibility in the height of it, in case it had to come down, if they weren't exactly level" (150.35-.48T). It was decided, "with the engineer", to change the original concept "to a site weld" (150.47T). In my judgment, it wasn't for a carpenter/builder to seek to overrule the structural engineers about such structural matters. As Mr Coulthurst said, in the building industry there are always other ways of doing things. I bear in mind the provisions of 5C(b), "the fact that a risk of harm could have been avoided by doing something in a different way does not of itself give rise to or effect liability for the way in which the thing was done". One must also have regard to the reality that relevant considerations informing decisions about structural design are often competing. The final design may involve a compromise in respect of some of the competing factors.
It is convenient to deal now with Mr McCaffrey's "pocket". As I have said more than once, the approach adopted by Mr McCaffrey depended upon the same concepts as those adopted by Mr Coulthurst. The real difference between them was the method of affixation of the "temporary" supports to the steel column and the timber frame of the adjoining wall. It is in this regard that Mr McCaffrey's supports were sturdier than the supports put in place by Mr Coulthurst. Also Mr McCaffrey doubled the size of the vertical timber prop. Mr McCaffrey himself spoke of "beef[ing] this up" (162.5T). He also had the benefit of the hindsight that Mr Coulthurst referred to. He said, "I wasn't taking any chances after seeing that accident" (162.7T).
Mr McCaffrey also had doubts or concerns about the approach Mr Coulthurst took of clamping the cleats in position: Well, how can you clamp anything onto this? You can't really do it. (163.10T) But he did not think the clamps could not be used in any circumstances. He said (163.25T): I don't see how you could clamp anything on, unless you put another block here and then clamped it that way. (Indicating an attachment to the timber prop).
If Mr McCaffrey had those doubts there is no evidence that he expressed them to Mr Coulthurst on or before 6 April 2016. It should be borne in mind that apart from this evidence, there is no evidence from either of the experts from which I could conclude that Mr Coulthurst's approach fell short of the standard of reasonable care for his own safety; except of course Dr Casey's evidence about the wear on Mr Coulthurst's clamps and how that might affect their performance. As I have already pointed out he did not say they were unserviceable or unsuitable for the task to which they were put (see [96] above).
It may also be that the substantial means of attachment adopted by Mr McCaffrey would have caused inconvenience when the steel fabricators came back to perform the site welds. Presumably at least its lateral components would need to be stripped to enable the welding to occur. And finally, Mr McCaffrey agreed that having regard to Mr Coulthurst's injury he felt compelled to "devise a kind of belt and braces type approach to [the] task" (165.23T). Again I bear in mind s 5C (b) and (c). The latter paragraph provides "the subsequent taking of action that would (had the action been taken earlier) have avoided the risk of harm does not itself give rise to or effect liability in respect of the risk …".
Moreover, so far as causation is concerned, there is no evidence as to how Mr Miles controlled and operated the excavator on 7 April 2016. There is no suggestion that the methodology adopted by Mr McCaffrey represents some standard approach adopted by carpenters/builders for work of this type. On the contrary, it was an ad hoc approach devised with the care borne of hindsight.
It is tempting to consider, knowing what we know now, better informed as it is by the evidence of Dr Casey and Mr Waddell, that it would have been better if Mr Coulthurst had signalled for Mr Miles to reverse the excavator slightly so that the steel beam was over the timber prop in a neutral position rather than under tension. But it does seem to me that that point adjudges the matter by the standards of engineers not carpenters. There is no evidence that establishes that the ins and outs of pendulum effects or points of oscillating motion are part and parcel of the specialised knowledge acquired by carpenter/builders. Neither Mr Coulthurst nor Mr McCaffrey were asked about that. Moreover, on the only evidence about the matter, the contribution of Mr Coulthurst's push and the subsequent movement towards him of the beam was 200mm and he was 600mm away from the steel beam, out of harm's way as he regarded it, but still close enough to observe the downward movement of the beam onto the prop to enable him to know that the operation had been successful and the slings could be removed. I am not satisfied that his position fails the tests of reasonableness. Moreover, I am not satisfied that pushing the beam back into position caused him to fall from the ladder and suffer injury. The relatively small degree of movement involved was not sufficient to knock him from the ladder or create a situation of peril in which he lost his balance and fell.
It also may have been better if he had waited until the beam was recumbent on the prop before applying the lateral supports. But it is difficult to know why that should be so. Both the hypothetical steel pocket and the timber pocket actually fashioned by Mr McCaffrey were designed to be in place before the beam was lifted into position. That may have made it more difficult to solve any problem that arose in the process of seating the beam. Of course, no problem arose on 7 April 2016, but the evidence does not show that these alternatives were superior in all respects to Mr Coulthurst's approach. His task involved a degree of difficulty but it was one he had performed many times and had developed proficiency in its execution. Moreover, he regarded its simplicity as a virtue. I am not persuaded that he was in error in this regard. He actually assembled the lateral support to his satisfaction successfully. On the evidence I have accepted, it was the manner in which the excavator was thereafter operated that caused his assembly to disassemble and the beam to swing out knocking him off the ladder.
As I have made clear, I accept that Mr Coulthurst designed and implemented the system for the performance of this task. But I am not persuaded that the evidence establishes that harm befell him because the system failed. Although the evidence does not descend into great detail, as Mr Miles said, the same team had performed "16 odd" lifts in the past without incident (191.35T). Admittedly those lifts involved large timber elements rather than steel. As I have said, it may be that the process was not identical and the evidence does not enable me to make that assessment. I am not persuaded Mr Coulthurst's approach constituted a failure to exercise reasonable care for his own safety. I am not persuaded that contributory negligence has been made out.

Orders

My orders are: 1. Judgment for the plaintiff against the first defendant on the question of liability with damages to be assessed without reduction for contributory negligence; 2. Dismiss the proceedings against the second defendant; 3. The costs of the proceedings to date are the plaintiff's costs in the cause; 4. List the matter before me for directions as to the further hearing of the matter at 10:00 a.m. on Wednesday 10 June 2020.

Amendments 02 June 2020 - Paragraph 113 - first line "JA" replaced with "JJA" 3 Headings between paragraphs 114 and 115 replaced with one heading. New heading reading - "The question of breach - Did Mr Miles breach his duty of care? 09 June 2020 - Representation - Correction to spelling of Counsel's name 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: 09 June 2020

Work Health and Safety Regulation 2011(NSW)

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