Abalos v Australian Postal Commission

The plaintiff commenced employment with the defendant as a coder in May 1974. She was employed in that position until 1979. Her duties required her, while sitting on a chair, to operate a coding machine by means of a keyboard. The chair was made of metal with a padded vinyl or plastic seat and backrest. It had a left-sided armrest, but did not have a right armrest. The machine was about 1,800 mm high and 900 mm wide, with a well for the operator's legs, into which a footrest could be placed. The machine had a centrally located window, divided horizontally, at the eye level of a seated operator. Letters were brought to the machine by a conveyor belt. Each letter appeared in the upper half of the window and then fell into the lower half where it was coded by the operator. The keyboard stood on a stand about 340 mm to the right of the centre line of the coding machine. Its height could be adjusted by about 70 mm; it could be rotated through 360 degrees. But the angle of the keying panel, which stood at 20 degrees to the horizontal, could not be altered. The operator depressed the keys of the keyboard to register either the numeric postcode on the letter or an alphabetical code which the operator deduced by studying the address. The keyboard, which Mathews J. said had nineteen keys, was for use by the right hand only. All alphabetical coding was effected by pressing two keys simultaneously. Using the keyboard required more skill than that normally required in using a typewriter. The operators were trained to perform 10,000 key strokes per hour, but they worked at their own speed. Each machine was adjusted so that no letter would drop into the window until the previous one had been coded. There was evidence that the average coding rate was about 1,000 to 1,100 letters per hour. Each letter required about five key strokes. A central electronic memory unit translated the keyed code into a combination of bar and dot impressions which were printed in a luminescent material on the back of the envelope. After a letter was coded, it was automatically deposited onto the conveyor belt running under the particular machine.

Late in 1977 the plaintiff was diagnosed as having lateral epicondylitis in both elbows. Lateral epicondylitis is the technical name for "tennis elbow". It is an inflammation of the muscular attachments of the lateral epicondyle, which is the protruding part of the humerus on the lateral aspect of the elbow joint. The extensor muscles of the forearm have their attachments on the lateral epicondyle and are affected by this condition. Medial epicondylitis is often known as "golfer's elbow". It takes the same form as lateral epicondylitis, except that the inflammation is in the muscular attachments of the flexor muscles of the forearm where they join the medial epicondyle.

The learned trial judge found that, between 1977 and 1980, the plaintiff suffered from bilateral epicondylitis, but that since that time her condition had been at least "partially overtaken by a functional component". Her Honour was inclined to the view that some minor organic basis for the plaintiff's complaints still existed. In addition, her Honour found that the plaintiff had suffered from medial epicondylitis at one time, but that this condition had subsequently subsided. At the time of the trial in July 1987, the plaintiff continued to suffer from intermittent pain in both arms, the right more so than the left.

The expert witnesses were in agreement that, apart from pre-existing injury, epicondylitis can only be caused by excessive use of the relevant muscles. Her Honour found that it was possible for the plaintiff's work to cause epicondylitis. She found that, during the course of their work, the coders held their forearm muscles in a state of tension and in a posture of ulnar deviation and/or dorsiflexion. If a person holds her arm in either of these postures for any appreciable time, the load on the extensor muscles is increased and is liable to cause lateral epicondylitis. Sustained palmar flexion or ulnar deviation also increases the load on the flexor muscles and is liable to cause medial epicondylitis. The learned trial judge found that the lateral epicondylitis of the plaintiff's right, but not left, arm was caused by her work as a coder.

Her Honour found that the injury which the plaintiff sustained was reasonably foreseeable. She accepted the evidence of Professor Ferguson, a pioneer in the study of ergonomics in this country. In the early 1970s Professor Ferguson, at the request of the defendant, undertook a survey of the mail coders. He was "appalled" at what he considered to be the inhuman production line operations in the coding room. He stated that simply from an inspection of the work it was quite foreseeable:

that at least a proportion of the operators would suffer muscle fatigue, discomfort, pain, and even potentially some more serious lesions or damage, damage of a number of types, including the generalized muscle injury called R.S.I. and more specific injuries, in particular in relation to the coding function lateral epicondylitis and carpal tunnel syndrome and I believe that they were likely also to suffer aches and pains of the lumbar spine and the neck and even in the other arm associated with their posture.

In evidence, Professor Ferguson said that, apart from minor adjustments to the "unsatisfactory work station", the whole system needed to be redesigned.

Her Honour found that Professor Ferguson had communicated his opinions about the operation to the defendant's representatives. She concluded:

that the defendant must have been made aware, in the early 1970s, of the risks of injury arising from adverse postural positions adopted by the coders in the normal course of coding operations. It was therefore incumbent upon it to ensure, through its training and supervision of the coders, that these adverse postures were not adopted.

The coders worked in a large room which contained five suites of thirty coding machines standing side by side. Only four suites were in operation during any single shift. Up to 120 coders worked on each shift. Each suite of coders had a supervisor. Her Honour found that "the instructors in the training programme and the supervisors in the coding room were themselves quite unaware of the potential risks inherent in the coding operations". As a result, coders were told merely that they should adopt the posture most comfortable to themselves and try to relax as much as possible. Her Honour found that this was ineffective to ensure the adoption of a safe operating posture. She accepted evidence that different people developed different techniques in order to carry out the same duties and were inclined to adopt postures which were comfortable in the short term, but which might be harmful in the long term. Accordingly, her Honour held that expert direction was required to ensure that individual operators adopted safe working styles. This was not done in relation to the plaintiff or the other employees in the coding room. Her Honour found that, if there had been proper training and supervision of coders given by people who had knowledge of the relevant risk factors and the skill to impart that information, the risk of injury in carrying out coding operations would have been minimal. The plaintiff would almost certainly not have sustained her injury.

Her Honour relied on the evidence and demonstrations of Mrs. Archer, a supervisor, in concluding that the coding operations were capable of being carried out with a minimal risk of injury to coders. A video cassette of Mrs. Archer operating a coding machine was tendered in evidence. In court Mrs. Archer gave numerous demonstrations of the hand movements involved in operating the keyboard. Her Honour held that these demonstrations showed that it was possible to depress the normal combinations of keys required in the coding operation without abduction of the arm. Her Honour said that Mrs. Archer made the operation appear extremely relaxed and simple, with a minimum of dorsiflexion or ulnar deviation. Her Honour concluded that, if all coders had worked with the same degree of ease and proficiency as Mrs. Archer demonstrated, the load on the forearm muscles would almost certainly have been insufficient to lead to any significant injury.

Accordingly, her Honour found that the defendant was in breach of its duty in not supervising the work of the plaintiff so as to ensure that she adopted a correct, relaxed posture while performing her work. In reaching this conclusion, her Honour made no reference to the evidence which Professor Ferguson had given on the issue of supervision. As appears below, the Court of Appeal thought that the effect of his evidence was that additional supervision would not have avoided the plaintiff's injury.

Leaving aside Professor Ferguson's evidence on the issue of supervision, the rest of his evidence would seem to establish that the defendant negligently caused the plaintiff's injury by requiring her to work in a system which exposed her to a risk of injury which was reasonably foreseeable and which could have been reasonably avoided by redesigning the system. But this was not the negligence which the plaintiff alleged. Perhaps counsel who appeared for the plaintiff at the trial, but not in this Court, was in possession of evidence that suggested that the cost of redesigning the system was disproportionate to the risk involved. For whatever reason, what, on the surface, would appear to be a clear case of negligence was never put in the courts below. Instead, the plaintiff's case was put in three other ways.

The first particular of negligence relied on alleged that the defendant was negligent in designing the system. Her Honour found that, when the system became operational in 1966, specialist ergonomists were aware that repetitive hand movements might have adverse health consequences. But she found that at that time this knowledge was "not available to the community at large". Accordingly, the first particular of negligence failed on the issue of foreseeability. The second particular alleged that the defendant was negligent in the maintenance of the coding machines. This allegation was based on the suggestion that the chairs were difficult to adjust, that seats would gradually lose height during the course of a shift and that the keyboard was sometimes very stiff so that strong pressure had to be applied to the keys in order to activate them. Her Honour found, however, that, when these defects were brought to the defendant's notice, steps were taken to rectify them. She found that there was no causal link between "these occasional maintenance problems and the injury sustained by the plaintiff". The third particular alleged that the defendant was negligent because the risk of injury inherent in the overall system could have been avoided if the coders had been given adequate training and/or supervision in relation to safe methods of conducting their operations. As I have said, her Honour found for the plaintiff on the issue of inadequate supervision.

The Court of Appeal held (Samuels and Meagher JJ.A., Mahoney J.A. dissenting) that her Honour erred in concluding that training or supervision would have protected the coders from the risk of injury which arose from the postures which the coders adopted. Samuels J.A. said:

matters of foreseeability and of causation have become mixed up. More than that, the production line conditions which appalled Professor Ferguson represented the system of work and the design of equipment with which her Honour had declined to find fault, so that neither of these components of the operation was tainted by any breach of duty. I would be inclined to infer without more that in those circumstances it can hardly be said that any amount of training or supervision would have sufficed to protect coders against posture forced upon them by the nature of the system of work and of the design of the equipment allotted to them. But Professor Ferguson makes the point explicitly. Samuels J.A. held that the conclusion "which must be drawn from Professor Ferguson's evidence is that no improvement in training or supervision would have overcome the adverse effects of the system". Consequently, his Honour held that there was no causal link between the plaintiff's injury and the lack of training or supervision.

Incorrect posture was dictated by the system. Yet her Honour found that there was no negligence either in initially devising or in subsequent maintenance of the system the Professor's complaints do not relate either to supervision or to instruction and training. Indeed, it is difficult to imagine how any amount of training or supervision could rectify any of the defects listed by the Professor. Yet her Honour found that lack of adequate training and supervision was the operative negligence of the [defendant].

With great respect, Samuels J.A. was in error in stating that the postures adopted were forced upon the coders by the nature of the system of work and the design of the equipment allotted to them. The whole point of her Honour's judgment on the issue of negligent supervision was that the work could have been performed in a relaxed way and without dorsiflexion or ulnar deviation or abduction of the right arm. Likewise, the comment of Meagher J.A. that incorrect posture was dictated by the system was erroneous. Meagher J.A. also erred in stating that her Honour found that there was no negligence in the subsequent maintenance of the system. The judgment of Samuels J.A. likewise seems to assume that her Honour found that there was no negligence in maintaining the system. But, as I have already pointed out, the plaintiff did not allege that the defendant was negligent in maintaining the overall system (i.e. maintaining the overall system of work as opposed to maintaining particular machines). Her Honour was never called upon to determine that issue.

Notwithstanding these errors in the judgments in the Court of Appeal, the question remains whether that Court was correct in holding that the effect of Professor Ferguson's evidence was that no amount of supervision would have eliminated or reduced the risk of injury and, if so, whether the Court of Appeal was entitled to reverse her Honour's finding based on evidence which she heard and demonstrations which she saw.

The evidence of Professor Ferguson was lengthy. But it focussed on the inadequacy of the system as a physical system of work. The question of supervision was directly addressed in only one small section of his evidence. Moreover, it is far from clear from that section of the evidence whether Professor Ferguson thought that no amount of training or supervision could have eliminated or reduced the risk of injury.

In his evidence Professor Ferguson said that the individual work station and its design required the operator "to adopt postures and actions which were predicated to cause at least discomfort, if not more severe symptoms". He said that the posture of which he complained was partly dictated by the visual demands of the task and partly by the action required of both hands. The right arm in a right-handed person was obliged to hang down to operate a keyboard situated below normal desk level and the placement of the keyboard required the operator to externally rotate the shoulder, extend the wrist and deviate the hand sideways to the right with the hand pronated. When the wrist was extended and deviated and the arm turned out at the shoulder, a static muscle tension was induced and that was an undesirable base for carrying out a rapid motor skill.

Professor Ferguson also criticised the design of the chair saying that having an armrest on only one side of the chair would guarantee that the person seated in the chair would be unbalanced because it would cause the person to elevate the left shoulder and tilt to the right. He commented that the angle of the keys would require the wrist to be extended and that the operator sometimes had to key a combination of codes which involved turning the right thumb under the palm. He said this method of operating the keyboard would cause the right elbow and right shoulder "to be abducted" with the consequence that the arm would be tense, the wrist extended and the shoulder abducted with possible ulnar deviation. Professor Ferguson saw the potential consequences of this method of operation as including lateral epicondylitis. He said that the keyboard dominated the posture that a person adopted because it caused the right shoulder to droop in relation to the left shoulder which was fixed by a high armrest. This meant that the operator would have to attempt to maintain balance in an unbalanced posture which would cause static muscle tension running all the way down the spine and tension in the muscles of the shoulder girdle. Professor Ferguson also said that he was unhappy about a job design where people had to work at speed, hour after hour, with a few minutes break on the hour and without a more flexible arrangement allowing variation in the work cycle.

Q. And was it possible for the operator to adopt a correct safe work posture in performing the work you saw? A. I am in trouble with the words "correct" and "safe".

Q. Ignore them. A. Well, can I make a comment then in relation to the question.

Q. Yes. A. I don't believe that it was possible for the operator to adopt a balanced posture. In other words, that the posture was obliged by the task that was such that there had to be some postural instability and therefore, muscle tension.

Q. Could a better posture have been adopted? Do you know what I am trying to say now? A. Yes, I understand what you mean. It would have been better to - it would have been possible to improve the posture to a limited degree by optimal adjustment of the chair and the position of Ex. 5, the keyboard, in relation to the size of the operator, having in mind that the position of the operator is part dictated by the visual demand of the task and part by the manipulative task. However, it would have been far better, and as far as I understand (I am not an engineer) but it would have been far better and reasonably simple to merely have relocated the keyboard, even without going into questions of the ergonomic design of the keyboard and of the hand actions which were - the women were instructed to use.

Professor Ferguson also said that the position and design of the keyboard would encourage the operator to rest the hand on the keyboard between the bottom row of the keys and the front edge of the keyboard which would encourage the wrist to extend. He thought that a forearm rest should have been used and positioned in a way which would enable tension to be removed from the forearm muscles allowing the fingers to operate freely.

Q. What is the relevance, or otherwise, of supervision? A. I don't want to go on giving an essay on the subject. I believe very strongly that supervision is critical

Q. Go on professor. A. When I was doing my study amongst the telegraphists in the early sixties, I came to the conclusion that much of their problems was brought about by faulty supervision and this is not to blame the supervisors. They weren't trained in the skills of being supervisors. They had too many people to supervise. They didn't have the same continually small group structure which is so important for effective supervision, where you can get communication up and down effectively and the supervisors weren't instructed in how to correct the operators in their posture and work method. Are you talking about the coders, amongst others or? A. Your Honour, I am sorry, yes, I meant to go on to say, I was first exposed to that experience very intimately in the sixties, in the early sixties and all my investigations since, including that of the coders, reinforces that view; certainly in respect of the coders it would have been impossible for the supervisors to have exerted their functions adequately. You had thirty women in each suite, if I can recall, in long rows and all operating at a fast rate and I don't think it was possible for them to have the close small group supervision that is essential for effective safe operation.

Professor Ferguson's evidence on the question of supervision is ambiguous. He may have meant that supervision was inadequate because there were too few supervisors or he may have meant that, given the system, useful supervision was impossible. I would read his evidence as meaning that there were not enough supervisors in the coding room to exert "their functions adequately". On that hypothesis, Professor Ferguson's evidence seems to imply that proper supervision would have been effective to some extent in reducing the risk of injury which was generated by the physical design of the system.

Moreover, Professor Ferguson said that individuals vary in their responses to the tasks "and the postures that are imposed on them". He pointed out that unskilled people were probably more prone to injury because they pushed the keys too hard and used an excessive amount of action in operating the keyboard. This evidence also suggests that proper supervision and training would have been beneficial. So too does his evidence in cross-examination to the effect that requiring keyboard operators to take breaks from work would assist in relieving postural stress and reduce the possibility of muscle damage as a result of fatigue. In re-examination, Professor Ferguson stated that, in the absence of particular training or supervision, an individual would "compensate" for the poor design of the equipment in the easiest manner. However, the method that the individual would think was the easiest way to compensate and the resulting posture adopted by the individual would not necessarily be the most beneficial posture from a medical point of view. This evidence also indicates the potential benefits which training and supervision could have provided.

Thus, most of Professor Ferguson's evidence was directed to the physical components of the system. He was highly critical of the design of the equipment used in the system. Indeed, the force of his criticism concerning the angle and positioning of the keyboard, the style of chairs used and the resulting poor posture suggests that he perceived the whole operation to be so fundamentally flawed that supervision of the coders would not have eliminated or reduced the risk of injury. But other parts of his evidence suggest that proper training and supervision could have reduced the risk of injury.

On balance, I think that the better conclusion to be drawn from Professor Ferguson's evidence is that more extensive supervision would not have eliminated the risk of injury but it might have reduced it. It is another question, however, whether the majority in the Court of Appeal were justified in using Professor Ferguson's evidence to reverse the trial judge's finding that more extensive supervision would have resulted in a minimal risk of injury even if the correct interpretation of Professor Ferguson's evidence is that more extensive supervision would not have avoided the plaintiff's injury.

In S.S. Hontestroom v. S.S. Sagaporack [1] , Lord Sumner pointed out that:

not to have seen the witnesses puts appellate judges in a permanent position of disadvantage as against the trial judge, and, unless it can be shown that he has failed to use or has palpably misused his advantage, the higher Court ought not to take the responsibility of reversing conclusions so arrived at, merely on the result of their own comparisons and criticisms of the witnesses and of their own view of the probabilities of the case. The course of the trial and the whole substance of the judgment must be looked at, and the matter does not depend on the question whether a witness has been cross-examined to credit or has been pronounced by the judge in terms to be unworthy of it. If his estimate of the man forms any substantial part of his reasons for his judgment the trial judge's conclusions of fact should, as I understand the decisions, be let alone. 1. [1927] A.C. 37, at p. 47.

Consequently, where a trial judge has made a finding of fact contrary to the evidence of a witness but has made no reference to that evidence, an appellate court cannot act on that evidence to reverse the finding unless it is satisfied "that any advantage enjoyed by the trial judge by reason of having seen and heard the witnesses, could not be sufficient to explain or justify the trial judge's conclusion": Watt or Thomas v. Thomas [2] .

In the present case, the learned trial judge's decision on the issue of supervision was based on the evidence of Mrs. Archer. In addition to hearing Mrs. Archer giving evidence, her Honour had the great advantage of seeing both a video cassette of Mrs. Archer operating the coding machine and the in-court demonstrations of her operating the keyboard. She did not refer to the evidence which Professor Ferguson had given on the issue of supervision. The learned trial judge formed the view that, for a person who performed the work in the manner which Mrs. Archer demonstrated, the risk of injury was minimal. Her Honour was not bound to accept the whole of Professor Ferguson's evidence concerning supervision even if it had the effect which the Court of Appeal thought it had. She accepted his evidence concerning the risk of injury which was inherent in the system and his evidence that he had communicated his views to representatives of the defendant. But she made no express findings about the rest of Professor Ferguson's evidence or his general reliability as a witness. If there is any inconsistency between Professor Ferguson's evidence and her Honour's findings concerning supervision, then she must be taken to have rejected that evidence. Certainly, she seems to have rejected his evidence that the postures adopted were partly dictated by the visual demands of the task and partly by the action required of both hands.

As I pointed out in Jones v. Hyde [3] , when a trial judge resolves a conflict of evidence between witnesses, the subtle influence of demeanour on his or her determination cannot be overlooked. It does not follow that, because her Honour made no express reference to the demeanour or credibility of either Professor Ferguson or Mrs. Archer, demeanour or credibility played no part in her findings on the supervision issue. But in any event, no matter how impressive Professor Ferguson's evidence may appear, it cannot claim the consideration of an appellate court to the extent necessary to overcome the advantage which her Honour enjoyed in seeing and hearing Mrs. Archer give evidence. There is simply no basis for concluding that, in so far as her Honour preferred the evidence and demonstrations of Mrs. Archer to the evidence of Professor Ferguson, she failed to use or palpably misused the advantage which she had of seeing and hearing the witnesses. In any event, her Honour may well have taken the view, not without justification, that Professor Ferguson's evidence on the issue of supervision was too limited and tenuous to outweigh the effect on her of the video cassette and in-court demonstrations given by Mrs. Archer.

1. (1989) 63 A.L.J.R. 349, at p. 351; 85 A.L.R. 23, at p. 27.

Accordingly, I would hold that the Court of Appeal was in error in reversing the finding of Mathews J. that proper supervision would have avoided the plaintiff's injury.

However, Mr. Bennett Q.C. for the defendant (respondent), sought to uphold the finding of the Court of Appeal on the basis that her Honour erred in so far as her findings imply that it was reasonably foreseeable that failure to supervise the employees gave rise to a foreseeable risk of injury. Mr. Bennett submitted that Professor Ferguson's evidence was directed to the foreseeability of the injury arising out of the system and not to the foreseeability of any injury arising out of the failure to supervise. This submission misconceives the issues in a negligence case and in particular a case brought by an employee against her employer. It was the risk of injury arising from the defendant's operations which was required to be reasonably foreseeable, not the risk of injury arising from the failure to adopt any particular alternative. As Mason J. said in Wyong Shire Council v. Shirt [4] :

In deciding whether there has been a breach of the duty of care the tribunal of fact must first ask itself whether a reasonable man in the defendant's position would have foreseen that his conduct involved a risk of injury to the plaintiff or to a class of persons including the plaintiff. If the answer be in the affirmative, it is then for the tribunal of fact to determine what a reasonable man would do by way of response to the risk. The perception of the reasonable man's response calls for a consideration of the magnitude of the risk and the degree of the probability of its occurrence, along with the expense, difficulty and inconvenience of taking alleviating action and any other conflicting responsibilities which the defendant may have. It is only when these matters are balanced out that the tribunal of fact can confidently assert what is the standard of response to be ascribed to the reasonable man placed in the defendant's position. 1. (1980) 146 C.L.R. 40, at pp. 47-48.

The question on the foreseeability issue was not whether the omission to provide proper supervision gave rise to a foreseeable risk of injury. It was whether the conduct of the defendant in requiring the plaintiff to work in this system gave rise to a reasonably foreseeable risk of injury. If it did, the plaintiff was exposed to an unnecessary risk of injury if the injury was reasonably avoidable and in all the circumstances the failure of the defendant to eliminate the risk was unreasonable. In the present case, as her Honour found, the system gave rise to a reasonably foreseeable risk of injury. That risk could have been avoided by redesigning the system. But her Honour found that it could also have been avoided by proper supervision.

The majority of the Court of Appeal erred in reversing the trial judge's finding that proper supervision of the coders would have made the risk of injury to the appellant minimal. The appeal should be allowed and the orders of the Court of Appeal should be set aside. The matter should be remitted to the Court of Appeal to determine the outstanding issues between the parties.