Citation : SMITH -v- BHP BILLITON LTD [2012] WADC 21

Negligence - Personal injuries - Accident on mine site - Whether respondent knew or ought to have known of the appellant's activity which led to the accident

Civil Liability Act 2002 (WA)

Mines Safety and Inspection Act 1994 (WA), s 13, s 15A

Adler v Australian Securities and Investments Commission [2003] NSWCA 131; (2003) 179 FLR 1

Leeder v Western Australia [2008] WASCA 192

Smith v BHP Billiton Ltd [2012] WADC 21

1 PULLIN JA: This is an appeal by the appellant against the judgment of Birmingham DCJ, who dismissed the appellant's claim for damages for personal injuries which he suffered at the Mount Whaleback mine site on 6 December 2005. The mine site was owned by the respondent. The respondent engaged MacMahon Contractors Pty Ltd (MacMahon) to carry out the mining activities at the mine site. The appellant was employed as a truck driver by MacMahon.

2 The appellant's injuries were suffered when, according to his testimony, he fell from a stack of two Haulpak tyres on which he was standing. The stack of tyres was on an island in an intersection of roads used by trucks on the mine site (intersection W19). The islands were constructed using windrows of waste soil with two Haulpak tyres being positioned one on top of the other at the ends of each of the two islands in the intersection. Waste soil was then loaded into the centre of the tyres to secure them in position. A jarrah stake was driven into the soil in each of the four stacks of tyres, and a two inch pipe to which 'keep left' signs were secured was placed over the top of each stake and hammered into the soil until firmly secured in place. Each stack of tyres was approximately 1.5 metres high and 3 metres wide.

3 The appellant testified that, on the day of the incident, he was in the process of cleaning one of the keep left signs with a rag. He was carrying a bucket with some water. The appellant gave evidence that no one instructed him to clean the signs, that it was solely his decision to do so and solely his decision to adopt the manner of doing the task. No one saw him performing this task.

4 Another MacMahon employee, Mr Lee, gave evidence that a superintendent, Mr Seymour, had instructed the appellant to clean the signs. That evidence was rejected by the trial judge because it did not accord with the appellant's evidence: Smith v BHP Billiton Ltd [2012] WADC 21 [113]. The appellant acknowledged in cross-examination that he had never seen anyone else cleaning the signs with a cloth while standing on the tyres [37]. He had worked on the mine site for nine months before the accident.

5 The appellant gave evidence that the soil in the other three stacks was firm underfoot and well compacted [293], and that he had cleaned the signs in those stacks without incident. He gave evidence that, in relation to the fourth stack, when he stepped into the soil in the centre expecting it to be solid, his leg unexpectedly sank into the soil, which he described as soft, powdery 'bulldust'. He said that this resulted in his leg sinking into the soil up to his crotch - to a depth of slightly less than a metre - and that, as he tried to extract his leg, he fell to the ground, striking his head on the ground and his knee on a rock [294]. The appellant claimed that, as a result of the accident, he suffered from nervous shock, right knee injury and right calf injury, and that he suffered a permanent right lower limb impairment and psychiatric illness, resulting in a loss of earnings and loss of earning capacity.

6 The trial judge found that the appellant did fall and that he did strike his right knee on 6 December 2005, but not in the manner that the appellant contended [316]. The trial judge found that he recovered to the point where he was capable of performing his pre-incident duties sometime before he was retrenched on 31 January 2007 [425]. He was certified fit for his pre-incident duties by his general practitioner, Dr Green, on 25 January 2007 [189].

7 The trial judge accepted the evidence of a Mr Jess, a Mr Durkin, a Mr Garnett and a Mr Terry about the composition and compaction of the soil in the tyres [302]. As a result of their evidence, the trial judge found that the soil in the middle of the tyre stack was of a gravelly type that was compacted and firm underfoot [303], and that it was not fine bulldust as the appellant claimed [307]. The trial judge found that, in consequence, he did not accept the appellant's evidence that his leg sank into the soil in the way that he had described [307].

8 Provisionally, the trial judge found that, if the respondent had known the appellant was to carry out the activity, there was no duty to warn because the risk of falling from the tyres and being injured was obvious [280]. Provisionally also, the trial judge dealt with a claim by the respondent that the appellant was guilty of contributory negligence and would have apportioned the liability of the appellant at 80% [385].

9 The trial judge found that the respondent owed a duty of care to the appellant at common law to exercise reasonable care for the appellant's safety on the mine site [273], and found that the defendant owed the appellant a duty under s 13 and s 15A of the Mines Safety and Inspection Act 1994 (WA) (MSI Act) [271] - [272]. This statutory duty was in terms that, as far as practicable, the respondent was to ensure that the persons who were on the mine site were not exposed to hazards (s 13) and, as far as practicable, the respondent was to provide and maintain a safe working environment. This required the respondent to provide and maintain a workplace and system of work whereby employees were not exposed to hazards, with a hazard being anything that may result in injury to a person or harm to the health of the person (s 15A, which applies s 9 of the MSI Act). It is only necessary to add that 'practicable' is defined in the MSI Act to mean 'reasonably practical' having regard to a number of listed considerations (s 4).

10 The undisputed evidence was that MacMahon, under its contract, was required to prepare a management plan and submit it to the respondent for approval [123]. Pursuant to the approved management plan, MacMahon was required to ensure that all signs were kept clean and in effective working order [124]. Under the contract, the respondent was permitted to conduct audits of MacMahon's compliance with the management plan [126]. Dynamic Earthmoving (Dynamic) was contracted by MacMahon to construct and maintain the haulage roads and the signage on the mine site [203].

11 Mr Lennox Terry, the proprietor of Dynamic, gave evidence which the trial judge found was a 'truthful and accurate account' [211]. Mr Terry rejected the suggestion that the type of soil used in the tyres was 'bulldust', or that bulldust had ever been used. He said that it would not have been possible to pick up such fine soil with a loader bucket, and that the sign would not have stood up in it if it had been used in the tyres [207]. Mr Terry testified that he was the person who cleaned the signs. He cleaned them from ground level using a squeeze mop, similar to that used to clean car windscreens, which was mounted on a 4-foot pole [208]. He had never seen anyone else cleaning the signs [209]. That system of cleaning the signs was in place before the appellant's accident [212].

12 Persons who worked for the respondent gave evidence. Mr Jess was employed by the respondent as a contract superintendent. Mr Garnett was retained by the respondent to oversee the MacMahon mining operations from a safety, environmental and production viewpoint. Both Mr Jess and Mr Garnett rejected the suggestion that the soil inside the tyres at the intersection comprised bulldust or loose, fine soil. Mr Jess said that if bulldust had been used inside the tyres, the signs would have blown over [130]. Mr Garnett did daily drive-arounds and audited the site from a safety perspective. He inspected road works, intersections and signage. Mr Garnett was aware that the maintenance of the intersection, including the signage, had been subcontracted by MacMahon to Dynamic, and was aware that Mr Terry was responsible for cleaning the signs [217]. He had seen people cleaning the signs at intersection W19 (ts 384). He gave evidence that he had never seen anyone cleaning the signs from two tyres, but that if he had seen anyone stand on two tyres to clean them he would have stopped them, as he considered that to work from the height of approximately 1.4 metres would be unsafe (ts 384). He stated that, in his view, such conduct would not have been tolerated by him, and that he had the power, which he exercised from time to time, to stand operations down and stop operations if there were safety breaches requiring correction.

The alleged breaches of duty and the trial judge's findings

13 The appellant's allegations of breaches of the duty of care owed by the respondent and the trial judge's findings were that:

(a) The respondent failed to warn the appellant of the risk of injury arising from climbing onto or into the tyres to access and clean the signs

14 This allegation was dismissed. The trial judge found that the appellant 'undertook the task on his own volition' without the respondent knowing or being reasonably expected to have known that it may occur [336], and that the respondent had no duty to watch over the appellant to ensure he was not injured whilst on a 'frolic' of his own [337]. Further, the trial judge found provisionally that any risk of injury from climbing onto the tyres to clean the signs was so obvious that it was not necessary for the respondent to warn the appellant of the risk of injury [338], [365] - [375]. The trial judge also found that the surface of the soil was compact and firm and did not pose any hidden danger or risk to the appellant that was not otherwise obvious, namely, any risk that may be associated with standing upon a tyre filled with soil 5 feet from the ground [339].

(b) The respondent failed to supply the appellant with a long handled broom with a scraper to clean the signs, instead of climbing onto or into the tyres

15 Based on the evidence of Mr Terry, the trial judge found that the system utilised to undertake the task of cleaning the signs required the use of a long handled squeeze mop from the ground, and that those charged with the responsibility to undertake the task did so [341]. The trial judge found that there was no reason for the respondent to expect that a truck driver employed by MacMahon would seek to do the work of others in a different and unsafe manner [342].

(c) The respondent failed to employee or design a system of cleaning the signs by instructing or requiring the appellant to use long shanked brooms

16 This is similar to the preceding allegation of breach of duty. The trial judge once again found that he was satisfied that a system was in place for the cleaning of the signs, that the persons instructed to do the task used that system, and that the respondent was not aware that the appellant would attempt to clean the signs in an unsafe way [346], [348].

(d) The respondent failed to ensure that the soil was solid and compacted

17 The trial judge rejected this allegation of negligence because of his finding that the soil inside the tyres was solid and compacted, and that in any event, the surface of the tyres was not a place of work or a work platform upon which employees were required to undertake their duties [350] - [351].

(e) The respondent failed to inspect the condition of the soil inside the Haulpak tyres to determine whether or not it was a safe working platform to stand on

18 This allegation was dealt with in the same way as earlier allegations. The trial judge noted again that there was no evidence that the respondent was aware, or ought reasonably to have known, that persons would stand on the tyres to clean the signs, that the respondent was aware that Dynamic had been engaged to clean the signs, and that the system adopted by Dynamic was the very system suggested by the appellant as a safe system of work [352]. Implicitly, the trial judge found that, in consequence, there was no requirement for the respondent to inspect the condition of the soil. In any event, as the trial judge found, the soil was firm underfoot and did not create any hazard [355].

19 As a result of the findings above, the trial judge found that there was no breach of the common law or statutory duties, stating that 'to the extent that the [respondent] owed any duty to the [appellant] as pleaded or at all, the [respondent] did not breach any such duty' and that 'it follows that the [appellant's] claim must be dismissed' [362] - [363].

Provisional findings of the trial judge Obvious risk

20 Notwithstanding having dismissed the appellant's claims, the trial judge turned to the 'remaining issues' that were live on the pleadings, which included the subject of 'obvious risk'. His Honour referred to s 5F, s 5N and s 5O of the Civil Liability Act 2002 (WA). The trial judge said that the decision of the appellant to climb onto the tyres to clean the signs was a decision taken by the appellant alone, that it was inherently risky, and that the respondent, acting with reasonable skill and care, could not reasonably have expected the appellant to conduct himself in such a manner [372]. The trial judge said that he was satisfied that the risk associated with standing on tyres approximately 1.4 metres high for any purpose, was so obvious that the appellant required no warning as to such risk, and it followed that the appellant's claim relying upon the respondent's failure to warn the appellant of such danger had to fail [373] - [374].

21 The trial judge also dealt provisionally with the subject of contributory negligence. The trial judge concluded that, if he was wrong about the circumstances of the appellant's fall, the harm suffered by the appellant would not have occurred but for the risk taken by the appellant, that contributory negligence had been established against the appellant, and that liability should be apportioned by 80%/20% against the appellant [385].

22 The trial judge also made findings about the injuries suffered by the appellant. The trial judge found that the appellant fell and cut his right knee [387]. The injuries to the appellant's knee were recorded as 'a laceration and swelling to right anterior patella, that is to say, a cut to the front of and swelling to his right knee' [389].

23 The trial judge observed that the appellant did not report any injury to his calf the next day to his doctor, Dr Ittermann, and that it was nine days after the incident that the appellant expressed concern about his calf to Dr Ittermann and then in relation to a possible thrombosis [391]. The trial judge found that he was not satisfied that the appellant suffered a restriction to his right calf to the extent that he claimed [403], and that the circumstances of the incident and the reported injury did not support a conclusion that the appellant injured his calf [404]. As a result, the trial judge found that he was not satisfied on the evidence that the appellant's calf injury occurred as a result of the incident [404].

24 There was disagreement between medical practitioners called to give evidence about what might have caused tightness in the calf muscle, which the appellant complained about sometime after the accident. Dr Williams, who was called by the appellant, saw the appellant on 30 October 2006 and 1 November 2006 for medico-legal purposes. Dr Williams diagnosed 'compartment syndrome' resulting in increased pressure in the right calf muscle [138]. Dr Williams considered that this was consistent with the appellant's description of the incident, that being that his leg went into the soil to 'calf level' when he fell backwards [139]. Dr Williams' initial report omitted any reference to the appellant's leg penetrating the soil, and this was not mentioned as a contributing factor to the appellant's injury [142]. However, his report was later amended to attribute the calf injury to the incident on 6 December 2005 [141] - [142]. Dr Williams considered that the trauma gave a stress strain to the muscle resulting in a 'low grade muscular myofascial strain, that is to say, the sheath covering the muscle that connected the muscle to the tendon' [143].

25 Dr Home, an occupational physician, examined the appellant at the request of the respondent's insurers. Dr Home considered the history given to him by the appellant, of pain from static pressure on the calf and pain present whilst driving but absent whilst walking, was inconsistent with a diagnosis of compartment syndrome [236]. Dr Home said that he was unable to find any objective evidence of induration, that is to say, hardness in the muscle, which would be expected if there had been bleeding in the muscle [237]. Dr Home said that the appellant revealed no sign of any ongoing functional disability, and that the appellant was fit to resume his pre-incident duties as a truck driver [237].

26 The trial judge noted that Dr Home's opinion as to the appellant's restriction was premised upon his clinical observations and findings, and not on the appellant's account of the incident and mechanics of the injury [247]. The trial judge found that Dr Home's evidence should be accepted [247], and preferred the evidence of Dr Home to that of Dr Williams [413].

27 His Honour also found that, even if the appellant did suffer any injury to his calf, the injury was of such a nature that no surgical intervention was required, and its treatment required nothing more than light exercise and perhaps some physiotherapy as recommended by Dr Williams in late 2006 [415].

28 As to the appellant's claim that he suffered a psychiatric illness, the trial judge considered the evidence of Dr Williams, Dr Manners and Dr Cheng. The evidence of Dr Cheng was that, when he saw the appellant, he suffered from an adjustment disorder, not a psychiatric illness, and that the disorder was not as a consequence of the injury, but rather a result of being made redundant [421] - [422].

29 The trial judge preferred Dr Cheng's evidence to that of the other two doctors [422].

30 The trial judge found that he was not satisfied that the appellant had lost capacity to engage in his pre-incident employment and that the appellant was capable of performing his pre-incident duties as a truck driver up until he was retrenched on 30 January 2007 [414]. The trial judge said that he was fortified in this view by the extent to which the appellant was able to engage in his usual occupation until he was retrenched [414]. Furthermore, Dr Green certified that the appellant was fit for work before he was retrenched. However, after he was retrenched, without any change in his physical condition, he was then certified by Dr Green as wholly unfit for work [414]. Because there had been no change in the appellant's condition after his retrenchment, the trial judge rejected Dr Green's evidence about the appellant's unfitness to carry out his pre-accident work [199] - [202], [445].

31 As to damages, the trial judge concluded that, to the extent that the appellant was entitled to be compensated, only a modest award was warranted [447]. His Honour provisionally assessed damages at $20,000 in respect of pain and suffering for the knee injury and a degree of discomfort for a period of six months [448]. The trial judge found that the injury could reasonably be expected to have resolved with modest exercise and perhaps some local physiotherapy [448]. His Honour also provisionally assessed medical and pharmaceutical costs at $1,500 [449].

32 There are nine grounds of appeal which, summarised, allege that:

(1) the trial judge erred in finding that the respondent discharged its duty of care or did not breach its duty of care, pursuant to s 9 or s 15A of the MSI Act, or at common law:

(a) by finding that the respondent delegated to MacMahon the task of cleaning the signs; and

(b) by finding that the respondent was not aware or ought not to have been aware that persons might clean the signs in a manner contrary to the system adopted by Dynamic, and that persons other than those employed by Dynamic might clean the signs;

(2) the trial judge erred in fact in dismissing the appellant's evidence that he fell from the stack of tyres;

(3) the trial judge erred in finding that there was no foreseeable risk from 'working at height';

(4) the trial judge erred in fact in dismissing the fall as the cause of the appellant's calf injury or psychiatric injury;

(5) the trial judge erred in law in dismissing the claim on the basis that the respondent did not have an obligation to warn the appellant of an obvious risk;

(6) the trial judge erred in law in finding that the appellant was on a 'frolic' of his own in cleaning the signs;

(7) the trial judge erred in fact in dismissing the appellant's claim for economic loss, this ground being dependent upon establishing that the appellant was unable to work because of calf injury or psychiatric injury or a combination of the two;

(8) the trial judge erred in fact and in law in apportioning 80% of liability to the appellant; and

(9) the trial judge erred in his assessment of provisional damages.

Ground 1 Did the trial judge find that the respondent could discharge its duty by delegation?

33 The first part of ground 1 is the submission that the trial judge erred by finding that the respondent could discharge its duty of care at common law and its statutory duty by employing an independent contractor, MacMahon. That submission misapprehends the trial judge's reasons. The trial judge did not find that, by employing an independent contractor, the respondent discharged its duty. In fact, the trial judge stated the opposite at [324], in the following terms:

[i]t was not open to the [respondent] to point to MacMahon and require MacMahon deal with the matter. The [respondent] retains primary responsibility to ensure that the necessary system was in place ...

34 The paragraphs to which the appellant refers, [328], [329] and [330], were paragraphs in which the trial judge considered what was reasonably required in discharge of the non-delegable duty. The recital of those paragraphs, which are set out below, makes this clear:

In my opinion, the duty owed to the [appellant] does not extend to requiring the [respondent] to establish a duplicate system to those implemented and maintained by MacMahon under the supervision of the [respondent]. Whilst the [respondent] remains primarily liable it is reasonable and practical to discharge its duty by requiring that such system provided and maintained by MacMahon and regularly auditing and inspecting the areas of operations at mine site to ensure compliance.

All that was required by the [respondent] to discharge its duty to the [appellant] was to do what was practicable. Accordingly, to the extent to which Dynamic had been engaged to construct and maintain the road works and signs, the system adopted by MacMahon would necessarily be the system in place for the purposes of the [respondent] in fulfilling its obligations pursuant to s 9 of the Act.

It follows that the system used by Dynamic involving the use of a long handled squeeze mop was for the purposes of this case, the system that maintained [sic] by the [respondent] in discharge of any duty owed to the [appellant].

Was the respondent aware or ought it to have been aware that the appellant would clean the signs from the tyres?

35 The second part of ground 1 alleges that the learned trial judge erred in finding that the respondent was not aware, and that the respondent ought not to have been aware, that the appellant would clean signs by climbing onto the tyres and doing so in a manner inconsistent with the safe system of cleaning adopted by Dynamic. This is the key point in the appeal. If this part of ground 1 fails, the appeal must fail.

36 Nothing the appellant pointed to in the evidence suggested that the respondent was aware, or ought to have been aware, that the appellant or any other persons on site would clean the signs at the intersection by climbing up onto the tyres. The evidence was all the other way.

37 Instead, the appellant's counsel sought to advance this ground by submitting that the respondent did not know that the system adopted by Dynamic for cleaning the signs at intersection W19 (which the appellant conceded was a safe system) was the system being used. It is irrelevant whether the respondent knew or did not know of Dynamic's system. The respondent's non-delegable duty required the respondent to avoid foreseeable risk of harm, and to take reasonably practicable steps to avoid a working environment in which employees were exposed to hazards. The respondent required MacMahon to provide such an environment, and MacMahon did so via Dynamic. The system employed by Dynamic was a safe system of work. Even if the appellant did not know that such a safe system of cleaning the signs was in place, it would not advance this ground of appeal.

38 In any event, the appellant's submission that the respondent did not know about the system used by Dynamic could not be sustained. The only inference open on the evidence is that the appellant did know about the safe system of cleaning the signs adopted by Dynamic. Mr Garnett said that he saw people cleaning the signs at intersection W19 (ts 384). The evidence was that, apart from the time when the appellant said that he had climbed up onto the stacks to clean the signs, the only method used to clean them was the method used by Dynamic. Mr Garnett said that he had never seen anyone standing on two tyres to clean the signs. Mr Garnett was not cross-examined on that evidence. Thus, the only inference open is that the appellant did know about the system being employed by Dynamic.

39 Ground 1 must be dismissed. It follows that the appeal must be dismissed. It is not strictly necessary to deal with the other grounds of appeal, but it is appropriate to deal with them in case other minds differ about ground 1.

40 It is possible to read the reasons as revealing a finding that the trial judge accepted that the appellant fell from the stack of tyres, but not as a result of his leg sinking into soft material. However, counsel for the appellant explained that she construed the reasons for decision as revealing that the trial judge found that the appellant did not climb up onto the tyres and therefore did not fall from them. Having read the reasons in that way, the appellant said that ground 2 should be construed as a challenge to that finding.

41 The parts of the reasons suggesting that the trial judge accepted that the appellant had climbed up onto the tyres and had fallen from the tyres, appears from a number of paragraphs. First at [101], although his Honour said that he did not accept that the appellant had given a truthful account of the accident, he referred to the appellant as 'exaggerating' the incident and its effect. At [109], the trial judge said that the appellant sought to maintain the erroneous description of the 'mechanism of his fall', adding that he found his evidence in relation to the 'circumstances' of the incident to be 'incapable of acceptance'. Later, under the heading 'Circumstance of the plaintiff's fall', the trial judge said at [312] that he did not accept that the incident occurred 'as the [appellant] has described'. This followed a rejection by the trial judge of the appellant's account that his leg had sunk into the 'bulldust or talc-like soil in the tyre to a depth approximating 1 metre'. At [315], his Honour found that the soil in the tyres at the intersection was 'firm underfoot'. This is followed immediately at [316] by an acceptance by the trial judge that the appellant 'fell and struck his knee on the morning of 6 December 2005', but a rejection that 'it' occurred in the 'manner' contended by him. These parts of the reasons suggest that the trial judge accepted that the appellant fell from the tyres, but not as a result of his foot sinking into the soil. To say that the appellant 'exaggerated' the incident, erroneously described the 'mechanism' of his fall, and that the fall did not occur in the 'manner' he described, is not the language one would expect to be used to make a finding that the appellant did not fall from the tyres at all.

42 However, as counsel for the appellant points out, the trial judge used other language which indicated that he did not accept that the appellant fell from the top of the tyre stack. In particular, the appellant points to [316] where his Honour said that he was unable to conclude on the evidence on the balance of probabilities 'as to where, why and how the [appellant] fell and suffered the injury he now complains of', and to [376] where, when provisionally considering contributory negligence, his Honour said 'if, contrary to my finding, the [appellant] did fall from the top of the stack of tyres when cleaning the sign, it is necessary to consider the issue of contributory negligence'.

43 Although the court did not call on counsel for the respondent to address the court on ground 2, he nevertheless did so by informing the court that he read the reasons in the same way as the appellant's counsel. On that basis, these reasons proceed by accepting the view of both counsel that the trial judge found that he was not satisfied on the balance of probabilities that the appellant fell from the tyres. Ground 2 challenges that finding.

44 The appellant sets out the evidence relied upon to indicate that the trial judge erred in making that finding. The undisputed evidence was that an event report was prepared based on information provided by the appellant. This reveals that the appellant reported the fact that he had a fall within half an hour after the incident. He showed signs of injuries consistent with a fall from the tyres, and the form records the appellant as having reported that 'the job' was done by 'standing on the tyre' (GAB 3).

45 Given the trial judge's finding that the appellant did suffer a fall, and there being no suggestion that he merely fell over on the ground or fell from any other location, the finding that the fall was not from the tyres was against the weight of the evidence. Ground 2 should be upheld. However, that conclusion does not assist the appellant in reversing the judgment unless it could be proved that the respondent knew, or ought to have known, that the appellant might climb onto the tyres to clean the signs. This was not proved and ground 1, which challenged the trial judge's finding on that point, has been dismissed.

The learned trial judge erred in law in finding that the circumstances of the accident as described by the appellant and in particular that the tyre was constituted either by bulldust, sand or gravel or otherwise were essential in determining whether there was a foreseeable risk of harm as a result of working at height.

47 This ground is ambiguous. It may be read as suggesting that the appellant challenges the trial judge's finding that the soil in the tyre did not consist of bulldust. This suggestion is encouraged by par 32 in the appellant's written submissions relating to ground 3. This paragraph lists evidence relating to the type of material found within the tyre.

48 However, during oral submissions, the appellant's counsel said that ground 3 should be understood as alleging that the trial judge erred in finding that there was no foreseeable risk of working at height.

49 This ground does not advance the appellant's appeal unless the appellant satisfies this court that the respondent knew, or ought to have known, that the appellant would go and clean the signs by climbing onto the tyres. The finding on that point was to the contrary and ground 1, which challenged that finding, has been dismissed.

50 All that it is necessary to say about this ground is that, if the appellant had proved that the respondent knew, or ought to have known, that he was 'working at height', then it would have been foreseeable that the appellant might suffer injury if he fell. However, because this was not proved, ground 3 should be dismissed.

51 This ground alleges that the trial judge erred in dismissing the accident as the cause of the appellant's calf injury [387] or psychiatric injury [437].

52 The trial judge reached his conclusion that the right calf problem, which was slight, was not caused by the accident. That finding is against the weight of the evidence. The incident report reveals that the appellant's calf was treated with an ice pack immediately after the incident. There is nothing else which suggests any other cause for an injury to the calf on that day. The appellant had a fall, as the trial judge found. If his calf required ice pack treatment immediately afterwards, that is a strong indicator that he did suffer a calf injury in the fall. Nine days later, a problem with his calf was noted by a treating doctor, Dr Ittermann. The trial judge only made a fleeting reference to the ice pack treatment, and then based his finding of no injury to the calf on the lack of the appellant's credibility and because the calf injury was not referred to in medical reports or in any other written material for nine days after the incident. This absence of report was not significant. It is clear that the knee was the more serious injury and that the injured knee attracted attention in the days immediately after the incident. The written record made immediately after the accident, and the references by medical practitioners to the injury, strongly supported the appellant's claim that his calf was injured in the fall. It does not follow that the appellant's calf was not injured at all merely because the trial judge did not find the appellant to be a credible witness, and because there was a lack of written references to the injury for nine days following the incident.

53 However, there is a second and more important issue, and that is whether there was any residual injury to the calf. That resulted in considerable debate among the medical practitioners. There was evidence both ways on the subject. The main contest was between Dr Williams and Dr Home. Ultimately, the trial judge accepted the evidence of Dr Home [413]. The judge's conclusion that there was no residual injury was corroborated by the medical opinion of Dr Green not long before the appellant was made redundant, in that Dr Green determined that the appellant was fit for his pre-incident work. That bears on subsequent grounds about the issue of loss of earning capacity and damages. That aspect of ground 4 must fail.

54 Insofar as ground 4 alleges error by the trial judge in finding that the appellant did not suffer any calf injury in the accident, the ground should be upheld. However, this does not result in the judgment being set aside because ground 1 has been dismissed.

55 As to the psychiatric injury, the appellant in submissions refers to evidence from the appellant that he was depressed because he was not working and was uncertain about his future. There was evidence that the appellant had been treated for depression, but ultimately, the trial judge found that he was not depressed but suffered from an adjustment disorder, and that this was because he had been retrenched and not because of his accident [422]. That finding was open to the trial judge. As mentioned earlier in these reasons, the trial judge preferred the evidence of Dr Cheng to that effect [422]. To that extent, ground 4 should be dismissed.

56 This ground alleges that the trial judge erred by finding that the respondent did not have an obligation to warn the appellant of an obvious risk. This was a provisional finding, because by the time that the trial judge considered this aspect, which had been raised by way of defence, a conclusion had been reached that there was no breach of duty because the appellant did not know, and ought not to have known, that the appellant was going to climb the tyres to clean the signs: see [360], [362]. Even if the finding had been that the respondent knew, or ought to have known, that the appellant would climb the tyres to carry out the cleaning of the signs, the finding of the trial judge was that the soil in the centre of the tyres was firm and not of the consistency described by the appellant [303]. The risk of otherwise falling from the tyres was so obvious that it did not require the appellant to be warned of the risk.

58 This ground challenges the trial judge's use of the word 'frolic', which is often used as a word to describe an employee using the employer's time or resources during employment for personal purposes. The trial judge did not use the word 'frolic' in that sense. He used the word to explain that the appellant, without anyone telling him to do so, embarked upon the cleaning of the signs himself. The word 'frolic' was not apt to describe what the appellant was doing, but it is clear that what the trial judge meant by the use of that word, was that the appellant was undertaking 'a task that he was not requested to do and could not reasonably have been expected to undertake' [347].

59 Although the trial judge infelicitously used the word 'frolic', the trial judge's reasons were otherwise clear.

61 This ground alleges that the trial judge erred in dismissing the appellant's claim for economic loss. This ground depends upon ground 4 succeeding and establishing that there was some residual calf injury or residual psychiatric injury caused by the accident. Ground 4 does not succeed to that extent.

62 There was evidence available to the trial judge that, at the time of the appellant's retrenchment on 30 January 2007, the appellant was capable of performing his pre-incident duties as a Haulpak driver. Dr Green had certified that he was so capable. It was only when he was retrenched that the appellant obtained a certificate of unfitness from Dr Green without any change of the appellant's condition. There was a great deal of evidence for and against the proposition that there was residual injury.

63 Error is not demonstrated merely by pointing to alternative findings of fact which might have been open on the evidence: Leeder v Western Australia [2008] WASCA 192 [84]; Adler v Australian Securities and Investments Commission [2003] NSWCA 131; (2003) 179 FLR 1 [17]. The appellant's submissions consisted merely of pointing to evidence which might have generated a different outcome, but did not justify any conclusion that that evidence outweighed the evidence that the appellant suffered no residual injury.

64 The trial judge was rightly cautious of the circumstances after the appellant was made redundant. The trial judge was clearly more impressed by the fact that, before the appellant was made redundant, he was able to carry out his work as a Haulpak driver, and that a doctor certified him as fit for that work: see [414], [426] - [430].

66 This challenges the trial judge's finding of contributory negligence, which was a provisional finding. Given the findings that the appellant

carried out the task of cleaning the signs without being instructed to do so in circumstances where there was a safe system of carrying out the work, there seems little doubt that liability should be heavily apportioned against the appellant.

68 The appellant asserts that the trial judge erred in his provisional assessment of damages. Essentially, the trial judge found that the appellant suffered no economic loss because he was working with MacMahon until retrenched, and thereafter completed two rehabilitation jobs, during which the only difficulties he had were with his back or neck which were not related to the accident.

69 Counsel for the appellant agreed that, because of provisions in the Civil Liability Act, unless the trial judge, unrestricted by the latter act, had assessed general damages at a figure exceeding $50,000, any award of general damages was limited to $2,500.

70 The appellant merely asserted, without any reference to authority, that damages were inadequate. That assertion does not reveal error.

72 Grounds 1, 3, 5, 6, 7 and 8 should be dismissed. Although ground 2 should be upheld and ground 4 should be upheld in part, the dismissal of ground 1 means that the appeal must be dismissed.