FEDERAL COURT OF AUSTRALIA Laurel Alma Hawkins v Comcare [2001] FCA 726 Workers Compensation – Employee working in poorly ventilated building and smoking permitted in the workplace – nine out of ten workers smoked – stressful work as a RAAF signals operator – worker took up smoking and became a heavy smoker – death from atherosclerosis – whether disease due to the nature of his employment – whether employment a contributing factor to the aggravation or acceleration of the disease. Administrative Appeals Tribunal Act 1975 (Cth) Safety, Rehabilitation and Compensation Act 1988 (Cth) Commonwealth Employees' Compensation Act 1930 (Cth) Compensation (Commonwealth Government Employees) Act 1971 (Cth) Migration Act 1958 (Cth): s 430 Behan v Australia Telecommunications Corporation (1990) 99 ALR 79 The Commonwealth v Bourne (1960) 104 CLR 32 Connair Pty Ltd v Frederiksen (1979) 142 CLR 485 Re Busby and Commonwealth of Australia (1987) 12 ALD 559 Marshall v East Holywell Coal Co (1905) 93 LT 360 Steel v Cammell Laird & Co [1905] 2 KB 232 The Commonwealth v Ockenden (1958) 99 CLR 215 Kavanagh v The Commonwealth (1960) 103 CLR 547 Hatzimanolis v ANI Corporation Ltd (1992) 106 ALR 611 Grant v Repatriation Commission (1999) 57 ALD 1 Hyundai Automotive Distributors v Australian Customs Service (1998) 51 ALD 45 Federal Broom Co Pty Ltd v Semlitch (1964) 110 CLR 626 Treloar v Australian Telecommunications Commission (1990) 97 ALR 321 Minister for Immigration and Multicultural Affairs v Yusuf (2000) 75 ALJR 1105 Dixon v Repatriation Commission (1999) FCA 582 Willis's Workmen's Compensation Acts 1925 – 1943 (UK), 37th ed. Matter No D 5 of 2001 LAUREL ALMA HAWKINS v COMCARE von DOUSSA J ADELAIDE (heard in Darwin) 17 DECEMBER 2001 IN THE FEDERAL COURT OF AUSTRALIA NORTHERN TERRITORY DISTRICT REGISTRY D 5 OF 2001 BETWEEN: LAUREL ALMA HAWKINS APPELLANT AND: COMCARE RESPONDENT JUDGE: von DOUSSA J DATE OF ORDER: 17 DECEMBER 2001 WHERE MADE: ADELAIDE (heard in Darwin) THE COURT ORDERS THAT: 1. The application appealing from the decision of the Administrative Appeals Tribunal dated 22 December 2000 is dismissed. 2. Each party shall bear her or its own costs of the application. Note: Settlement and entry of orders is dealt with in Order 36 of the Federal Court Rules. IN THE FEDERAL COURT OF AUSTRALIA NORTHERN TERRITORY DISTRICT REGISTRY D 5 OF 2001 BETWEEN: LAUREL ALMA HAWKINS APPLICANT AND: COMCARE RESPONDENT JUDGE: von DOUSSA J DATE: 17 DECEMBER 2001 PLACE: ADELAIDE (heard in Darwin) REASONS FOR JUDGMENT 1 This is an appeal brought under s 44(1) of the Administrative Appeals Tribunal Act 1975 (the AAT Act) from the decision of the Administrative Appeals Tribunal (the Tribunal) given on 22 December 2000. An appeal under s 44 lies to this Court only on a question of law. 2 By its decision the Tribunal affirmed a decision of a delegate of the respondent, Comcare, denying liability to pay compensation under the Safety, Rehabilitation and Compensation Act 1988 (the 1988 Act) in respect of the death of the applicant's late husband, Robin Albert Charles Hawkins (Mr Hawkins) who died aged 61 years on 7 June 1997. 3 The following summary of the background facts which gave rise to the applicant's claim for compensation is taken from findings of fact made by the Tribunal. The facts found were either common ground, or were based on undisputed evidence. 4 Mr Hawkins was born on 7 April 1936. He served as a member of the RAAF from 29 January 1958 to 28 January 1975. His service was as a specialist signals operator. In that capacity he was engaged in work that was of a secret kind. During his service he held the following postings: · 30 January 1958 – 10 May 1958: Recruit Training Unit in Rathmines undergoing training as a signals operator. · 10 May 1958 – 12 September 1958: RAAF School of Radio in Ballarat. · 12 September 1958 – 5 August 1960: 3 Telecommunications Unit at Pearce in Western Australia (Pearce). · 6 August 1960 – 14 March 1963: Base Squadron Butterworth Det A at Hong Kong (Hong Kong). · 15 March 1963 – 19 June 1964: Pearce. · 20 June 1964 – 18 December 1966: Hong Kong. · 19 December 1966 – 3 January 1971: Pearce. · 4 January 1971 – 14 January 1973: Darwin. · 15 January 1973 – 21 January 1975: Pearce. · 22 January 1975 – 28 January 1975: Amberley. 5 The applicant and Mr Hawkins were married in 1963, having met shortly after Mr Hawkins returned from his first Hong Kong posting. 6 Mr Hawkins died from coronary atherosclerosis. The opinion of the pathologist who conducted a post mortem report for the coroner, which the Tribunal accepted, was that coronary atherosclerosis was the condition leading directly to death but that other significant conditions contributing to death were smoking, an old myocardial infarction, and chronic lung abscesses. 7 Mr Hawkins did not smoke before enlisting or before his first posting to Hong Kong in 1960. He was a fairly heavy smoker when he returned from that posting. Mr Hawkins smoked forty cigarettes a day from the time that he commenced to smoke. He continued to smoke at that rate throughout his service with the RAAF and after his service until about 1985 when he suffered a heart attack. His rate of smoking reduced to about twenty-five cigarettes per day thereafter. 8 During his first posting at Pearce Mr Hawkins worked in an old communications building (the old building) which was described in the evidence as sub-standard and primitive. It comprised a sunken concrete building divided into two sections each about twelve to fourteen metres long by three to four metres wide. The building had no windows and only one door which was kept locked at all times. Ventilation was poor. The building contained twelve to fourteen operators during each shift. The shifts were eight hours in length but could be longer. The Tribunal held that approximately nine out of ten of the signal operators smoked and that they did so during the course of their working day. One witness, Mr Nelson, who worked in the old building at Pearce said that the "air was constantly blue with smoke". He said operators brought their own cigarettes to work and shared them freely with co-workers. Cigarettes were also available from an honour box in the building. 9 The Tribunal found that a pool of blue/grey smoke hung from the ceiling during all shifts except during the midnight to 8 a.m. shift, when there were fewer signal operators working. 10 The Tribunal held that signal operators found their work at Pearce stressful and caused them anxiety. Because of the nature of their work, which they were not free to discuss, they socialised together, and when they did the signal operators all smoked. 11 In Hong Kong, Mr Hawkins and the other signal operators stationed there, worked alone in small cabins located in paddy fields. The cabins measured some six feet by six feet. The work was held to be stressful and caused signal operators anxiety, like the work at Pearce. 12 Evidence led at trial disclosed that in about 1965 the old building at Pearce was replaced by a new building that was better ventilated and more spacious. However, no specific findings were made by the Tribunal as to the date when operations transferred from the old building to the new, or as to the effectiveness of the ventilation in the new building in removing smoke. It is clear from the findings of the Tribunal that signal operators, including Mr Hawkins, continued to smoke in the new building whilst they were on duty. 13 The applicant's statement of facts issues and contentions filed with the Tribunal alleged that Mr Hawkins' death was due to a disease or diseases that were materially contributed to by "his passive smoking" and/or alternatively his smoking. Evidence was given at trial by a cardiologist, Professor A J West. On his evidence the Tribunal found that Mr Hawkins' exposure to passive cigarette smoke whilst he was working in the old building at Pearce was the equivalent of smoking one or two cigarettes each day. 14 Other medical evidence established that Mr Hawkins had suffered from pneumonia in 1969. At that time it was discovered that the lower lobe of his lung was severely compressed, and following surgical intervention the lower lobe expanded to normal size in appearance. He also suffered ventricular fibrillation in July 1989 at which time a bronchoscopy revealed signs consistent with long standing tuberculosis. The pathologist's findings when the autopsy was carried out disclosed severe calcifying atheroma, chronic obstructive airways disease, but negatived the earlier diagnosis of tuberculosis. 15 It is clear from the reasons of the Tribunal that the Tribunal accepted Professor West's evidence about Mr Hawkins' smoking and exposure to smoke. The Tribunal summarised its findings on that evidence as follows: "In cross-examination, Dr West said that he could not find any articles considering the effects of passive smoking upon a smoker. The studies usually concentrated upon smokers and non-smokers. The effects of passive smoking in a non-smoker were, at the most, one to two cigarettes a day. As Mr Hawkins was smoking 40 cigarettes each day, the additional effects of his passive smoking were likely to be very small. No one knows if there is an upper threshold above which cigarettes will cease to have further adverse effects. It is very hard to determine the dose of nicotine from passive smoking. He could not measure the dose that Mr Hawkins would have received from passive smoking in his working environment even though he was told that 90% smoked. Dr West acknowledged that passive smoking could have played a role in Mr Hawkins' condition. The role, though, would have been small and it was not a probable role. The greater the exposure to smoking, the more likely it is that a person will die from smoking related illnesses. He also agreed that the greater the exposure to smoke, the more accelerated a disease will be. The causes of death from smoking related diseases were principally due to vascular disease and cancer. The most common is coronary artery disease." 16 The Tribunal correctly identified that the applicant's claim was made under the 1988 Act, although that Act came into force years after Mr Hawkins had completed his service with the RAAF. Pursuant to s 124(1) of the 1988 Act, the Act applies to an injury, loss or damage suffered by an employee whether before or after the 1988 Act came into operation on 1 December 1988. A person is entitled to compensation under the 1988 Act in respect of an injury, loss or damage suffered before 1 December 1988 if compensation was, or would have been, payable to the person in respect of the injury, loss or damage under the Commonwealth Workmen's Compensation Act 1912 (Cth), the Commonwealth Employees' Compensation Act 1930 (Cth) (the 1930 Act) or the Compensation (Commonwealth Government Employees) Act 1971 (Cth) (the 1971 Act): see s 124(1A) of s 124(2) of the 1988 Act. The transitional provisions in the 1988 Act keep alive rights and liabilities which have arisen under the previous Acts including the 1971 Act: see Behan v Australian Telecommunications Corporation (1990) 99 ALR 79 at 84. 17 The 1930 Act was in force and had application to Mr Hawkins' service until the 1971 Act came into force on 1 September 1971. 18 For reasons which appear below, the Tribunal decided the applicant's claim by reference to provisions of the 1930 Act, and did not consider provisions of the 1971 Act. One of the grounds of appeal before this Court is that the Tribunal erred in not considering the provisions of the 1971 Act. Provisions in the legislation include: 1930 ACT "Section 4(1) 'Injury' means any physical or mental injury and includes the aggravation, acceleration or recurrence of a pre-existing injury. Section 9(1) If personal injury by accident arising out of or in the course of his employment by the Commonwealth is caused to an employee, the Commonwealth shall, subject to this Act, be liable to pay compensation in accordance with the First Schedule to this Act. Section 10(1) Where – (a) … (b) the death of an employee is caused by a disease; and the disease is due to the nature of the employment in which the employee was engaged by the Commonwealth, the Commonwealth shall, subject to this Act, be liable to pay compensation in accordance with this Act as if the disease were a personal injury by accident arising out of or in the course of his employment." 1971 ACT "Section 29 (1) Where – (a) an employee contracts a disease or suffers an aggravation, acceleration or recurrence of a disease; and (b) any employment of the employee by the Commonwealth was a contributing factor to the contraction of the disease or to the aggravation, acceleration or recurrence, as the case may be, whether or not the disease was contracted or the aggravation, acceleration or recurrence was suffered in the course of that employment; the succeeding provisions of this section have effect. (2) If – (a) The death of an employee; … results from the disease, or from the aggravation, acceleration or recurrence of the disease … then for the purposes of this Act, unless the contrary intention appears – (f) the contraction of the disease, or the aggravation, acceleration or recurrence, as the case may be, shall be deemed to be personal injury to the employee arising out of the employment of the employee with the Commonwealth; and (g) the date of the death … shall be deemed to be the date of the injury." 19 In considering liability, the Tribunal observed at the outset: "As the claim is based on those periods of Mr Hawkins' service at Pearce and Hong Kong, it is the 1930 Act to which I must have regard. That is so as Mr Hawkins completed his last period of service in those two locations in January 1971 and so before the commencement of the 1971 Act." This statement is not literally accurate as Mr Hawkins returned to Pearce from 15 January 1973 to 21 January 1975, and the Tribunal's failure to consider this period is raised by one of the grounds of appeal. I doubt, however, whether the Tribunal overlooked the last period of employment at Pearce. Rather, I think that the reasons are unfortunately expressed, and that the Tribunal excluded consideration of the last period at Pearce for the reason that by then the signal operations were conducted from the new premises where ventilation was improved, and the evidence failed to disclose that passive smoking was a problem. Further, the primary case advanced on the applicant's behalf by her counsel in final submissions was that the nature of the employment of Mr Hawkins contributed to the fact of his commencing smoking cigarettes. There was, however, an alternative submission put that it was likely that Mr Hawkins was exposed to more cigarette smoke both through consuming more cigarettes and indirectly through passive smoking in the course of his employment than he otherwise would have been so as to lead him to die earlier than he would otherwise have done. Counsel for the applicant now contends that the alternative submission was intended to include the totality of Mr Hawkins' employment, including the last period at Pearce, and that an error of law occurred because the application of the 1971 Act in relation to that period of service was not considered. 20 Confining its consideration to the 1930 Act, the Tribunal held that: · Exposure to passive smoking at Pearce could constitute an "accident" within the meaning of s 9, and that exposure to passive smoking did occur at Pearce equivalent to the smoking of one or two cigarettes each day. However, on the evidence of Professor West the Tribunal was not satisfied that this passive smoking, on top of the personal smoking of forty cigarettes per day by Mr Hawkins "caused or aggravated the atherosclerosis from which he died". · Mr Hawkins' own smoking habit did not arise in circumstances that gave rise to liability under s 9 of the 1930 Act. The Tribunal summarised its conclusion on this point by saying that it was not satisfied that Mr Hawkins' smoking, and so his coronary atherosclerosis, was personal injury to him by accident arising out of or in the course of his employment by the Commonwealth. · The claim also failed under s 10 of the 1930 Act. The Tribunal discussed The Commonwealth v Bourne (1960) 104 CLR 32, Connair Pty Ltd v Frederiksen (1979) 142 CLR 485 and re Busby and Commonwealth of Australia (1987) 12 ALD 559, being authorities which elucidated the requirement of s 10 that a disease, to be compensable, must be "due to the nature of the employment" in which the employee was engaged. From these cases the Tribunal identified the relevant test, correctly in my view, as whether the employment tended to cause, aggravate or accelerate the relevant disease, in the present case the coronary atherosclerosis which caused Mr Hawkins' death. The Tribunal held that it did not. The Tribunal summarised its reasons for this conclusion as follows: "That is so because I am not satisfied that the nature of his employment tended to cause or contribute to his smoking, which in turn led to his coronary atherosclerosis, or that the passive smoking, to which the nature of his employment did expose him, tended to do so. I am not satisfied that the stressful nature of signals operators' employment led to their commencing to smoke. I accept that smoking could be regarded as a reliever of stress but I am not satisfied in this case that signals operators saw it in that way. The nature of their employment did, on the other hand, expose them to passive smoking in that smoking was permitted and the RAAF assisted smokers by making cigarettes readily available. On the evidence, however, I am not satisfied that the smoking of the majority of signals operators or the availability of cigarettes caused or contributed to their becoming addicted to nicotine and so commencing to smoke. I am also not satisfied that passive smoking to which signals operators were exposed during their shifts is such that it contributed to his coronary atherosclerosis. Dr West's evidence is that passive smoking may equate with smoking one to two cigarettes a day but, apart from the reference in a letter to a study in 1987, there is no evidence of its likely effect where the nature of the employment is that the vast majority of employees smoke considerably more than one to two each day." 21 Before turning to the grounds of appeal, I return to the Tribunal's conclusion that Mr Hawkins' own smoking did not constitute personal injury arising out of or in the course of his employment. In my opinion this conclusion is undoubtedly correct, but for reasons which differ from those given by the Tribunal. The claim made by the applicant is one which plainly rests upon the fact that Mr Hawkins died from a disease of very gradual onset. So gradual was the onset that it is impossible to identify any event that could constitute "injury by accident". 22 The expression "injury by accident" from the time when it was first used in workers compensation legislation, in the United Kingdom in 1897, has been accorded a meaning by the courts which has been gradually extended over time. The history of this development is outlined by Viscount Caldecote LC in Fife Coal Co v William Young [1940] AC 479 at 483 – 487. In that case a worker whose employment required him to kneel for long periods gradually developed a loss of muscle power in his right foot. On 27 April 1938 the foot became numb and led him to stop work. A diagnosis of "dropped foot" was made, i.e. paralysis of the muscles of the leg caused by pressure on the peroneal nerve. The House of Lords held that the worker suffered injury by accident on 27 April 1938. The Lord Chancellor at 483 noted that a fortuitous and unexpected event was no longer required, and approved a statement of Lord M'Laren in Stewart v Wilsons and Clyde Coal Co Ltd (1902) 5 F.120 that: "If a workman in the reasonable performance of his duties sustains a physiological injury as a result of the work he is engaged in … this is accidental injury in the sense of the statute." 23 It was possible in the circumstances of that case to identify the happening of a physiological injury on 27 April 1938 which constituted "injury by accident" because what happened on that day transformed the worker from a man who was not suffering from dropped foot into a man who was (see the speech of Lord Atkin at 488). The Lord Chancellor at 484 – 485 referred to the difficulty that will confront a worker who seeks to rely on the happening of "injury by accident" in the course of a progressive disease: "When the workman's claim is in respect of a progressive disease the difficulty of pointing to a definite physiological change which took place on a particular day is, in general, likely to be almost insuperable, and in 1906 Parliament, in the case of certain diseases and later by an enlargement of the schedule of industrial diseases, relieved the workmen in the specified cases of this obligation. But if the circumstances of any claim in respect of incapacity due to disease are such as to make it possible to discharge this burden, I see no reason for thinking that what is called a disease is different in principle from a ruptured aneurism as in Clover, Clayton & Co. Ld v Hughes [1910] AC 242, or heart failure as in Falmouth Docks and Engineering Co., Ld v Treloar [1933] AC 481." 24 Lord Atkin at 488 – 489 said: "It is necessary to emphasise the distinction between 'accident' and 'injury', which in some cases tend to be confused. No doubt the more usual case of an 'accident' is an event happening externally to a man. An explosion occurs in a mine, or a workman falls from a ladder. But it is now established that apart from external accident there may be what no doubt others as well as myself have called internal accident. A man suffers from rupture, an aneurism bursts, the muscular action of the heart fails, while the man is doing his ordinary work, turning a wheel or a screw, or lifting his hand. In such cases it is hardly possible to distinguish in time between 'accident' and injury; the rupture which is accident is at the same time injury from which follows at once or after a lapse of time death or incapacity. But the distinction between the two must be observed." 25 In the examples given by Lord Atkin it is possible to identify the happening of an accident involving physiological change which occurred at work. In the present case, to allow a claim for his death under s 9 it would be necessary for the Tribunal to be satisfied that death resulted from a definite physiological change in the progress of the atherosclerotic disease which took place at an identifiable point in time in the course of his employment. There is nothing in the material before the Tribunal which could have enabled the Tribunal to be so satisfied. 26 Cases before the 1906 amendments to which the Lord Chancellor referred included the occupational diseases of "beat hand" (Marshall v East Holywell Coal Co (1905) 93 LT 360), and lead poisoning (Steel v Cammell Laird & Co [1905] 2 KB 232) where the worker failed because the disease was not "injury by accident", there being no event the date of which could be fixed with some degree of definiteness. See Willis's Workmen's Compensation Acts 1925 to 1943 (UK), 37th ed., at 14 – 17. 27 The Commonwealth v Ockenden (1958) 99 CLR 215 was a case decided by the High Court of Australia under the 1930 Act, following the 1948 amendment which substituted the conjunction "or" for "and" in the phrase in s 9 "arising out of and in the course of his employment". It concerned a claim for compensation for incapacity resulting from the progression of a heart disease that was not attributable to the employment. The claim failed because it was not possible for the worker to identify a particular incident involving physiological change which occurred in the course of his employment which could constitute "injury by accident". The case is to be contrasted with Kavanagh v The Commonwealth (1960) 103 CLR 547 where physiological change at a particular point in time (a ruptured oesophagus caused by vomiting) could be identified. 28 In Ockenden's case, Dixon CJ, Fullagar and Taylor JJ said at 223 – 224: " … the traditional view must still prevail that a physiological change, sudden or otherwise, is not an injury by accident arising in the course of the employment unless it is associated with some incident of the employment. Indeed, to hold otherwise would be to strip the word 'accident' of all meaning by treating as such any distinct physiological change which is nothing more than the sole and inevitable result of the ravage of disease." 29 On the facts of the case their Honours pointed out at page 224 that it was impossible to say when Mr Ockenden's heart condition became patent although the trial judge thought that this had occurred at some stage in the six months before his disease was diagnosed. Their Honours continued at 224 – 225: "In that respect the case is quite unlike cases of sudden physiological change where either the change itself or its consequences, or both, become manifest contemporaneously. However his Honour thought that inability to determine when the change occurred was not a matter of importance; if, in fact, it was possible to say that such a change had taken place then the respondent had suffered injury by accident. But if the respondent did, as was found, sustain personal injury by accident it is clear that neither the respondent nor anybody else was aware of it at the time. Nor indeed is it possible now to say more than that as the condition of the aortic valve progressively and gradually deteriorated a point was reached where some slight leakage commenced to occur and, subsequently, and, no doubt, after further progressive deterioration, an audible murmur was detected. This appears to be the correct view on the facts of the case and, that being so, it is impossible to hold, even on the most benign view of what may be held to be an 'injury by accident', that personal injury by accident was caused to the respondent." 30 The Tribunal's conclusion that Mr Hawkins did not suffer personal injury by accident arising out of or in the course of his employment rested on the basis that there was no connection between Mr Hawkins taking up smoking and his employment, other than that he apparently commenced to smoke whilst he was first stationed in Hong Kong. In the course of its discussion on this topic, the Tribunal made a number of findings of fact which are relevant to grounds of appeal which have been argued before this Court. Those findings include: · On the basis of Professor West's evidence the Tribunal was satisfied that a smoker becomes addicted to the nicotine in cigarettes and continues to smoke because of that addiction. However, Professor West's evidence failed to satisfy the Tribunal that Mr Hawkins' passive smoking from the time he joined the RAAF in 1958 until 1963 led to his being addicted to nicotine so that he started to smoke himself in 1963. · The Tribunal accepted that work at Pearce and in Hong Kong was stressful. However, Mr Hawkins had not started to smoke at Pearce even though he was surrounded by people who smoked. In Hong Kong he was out of the smoking environment of Pearce and away from any peer pressure that he might have felt from fellow employees in Pearce. The Tribunal considered that it remained a matter of conjecture whether anxiety arising from his employment, or peer pressure in a social environment not related to his employment, or some other reason led to him commencing to smoke. The Tribunal said it was unable to find a chain of causation between his employment and his smoking so that the latter could be said to have arisen out of the former. · The Tribunal accepted that Mr Hawkins and his other signal operators tended to socialise together or with their families to the exclusion of others because of the secretive nature of their work but those social occasions were not mere intervals or interludes within an overall period or episode of work such as to bring them within the notion of events occurring "in the course of" his employment. In this respect the Tribunal made reference to Hatzimanolis v ANI Corporation Ltd (1992) 106 ALR 611 where at 617 – 618 Mason CJ, Deane, Dawson and McHugh JJ said: "Accordingly, it should now be accepted that an interval or interlude within an overall period or episode of work occurs within the course of employment if, expressly or impliedly, the employer has induced or encouraged the employee to spend that interval or interlude at a particular place or in a particular way …" 31 I turn now to the grounds of appeal. Eleven errors of law are alleged by the applicant, although in some respects the grounds overlap. Ground A 32 The Tribunal was wrong in law limiting its investigation of the causes of the disease, the cause of death, to passive smoking and smoking related stress. 33 It is contended that the Tribunal did not carry out a sufficiently detailed investigation whether smoking was "part and parcel of the nature of the employment". It is submitted that smoking was part of the culture of employment and no attempt was made to improve ventilation because of security concerns. In these circumstances it is said that smoking formed part of the employment. 34 I do not accept the argument that the Tribunal fell into an error of law for failing to carry out a sufficiently detailed investigation of the material before it. On the contrary, the Tribunal published long and detailed reasons which discussed the various matters which had been raised in the course of evidence and submissions before it. The applicant's case was put on the basis that the nature of the employment contributed to the fact that Mr Hawkins commenced to smoke. This was said to arise for three reasons: first, the immense exposure to cigarettes and cigarette smokers, both at work and socially; secondly, from peer pressure; and thirdly because Mr Hawkins would have experienced a degree of stress and anxiety related to his employment. The Tribunal considered each of these matters and gave reasons why it was not satisfied that Mr Hawkins took up smoking because of any one of them. These reasons were given in the course of the Tribunal's discussion whether Mr Hawkins own smoking gave rise to compensable personal injury by accident under s 9 of the 1930 Act. 35 The findings of fact, and the conclusion of the Tribunal was plainly open on the evidence. Although smoking was permitted in the workplace the Tribunal was not satisfied that either the fact that smoking was allowed, that other people smoked, or that the employment was stressful was causally related to Mr Hawkins smoking. Ground B 36 The Tribunal was wrong in law in confining the commencement and/or increase of smoking to a specific location and period rather than examining all of the employment related smoking periods. The Tribunal also erred in law in failing to consider the application of the provisions of the Compensation (Commonwealth Government Employees) Act 1971. 37 As I have earlier indicated, the Tribunal confined itself to a consideration of the 1930 Act, and did not consider whether events which occurred after the 1971 Act came into force gave rise to liability under that Act. From 1 September 1971 to 14 January 1973 Mr Hawkins was stationed in Darwin. No evidence was led at trial as to the conditions that prevailed in Darwin although the applicant in her evidence said that Mr Hawkins had described the Darwin workplace as "the Hilton of the workplaces he had worked in". From 15 January 1973 until 21 January 1975 (effectively the end of his employment) he was again stationed at Pearce. At that time, however, the signal operators were in the new premises, and the evidence fails to give detail of that environment. 38 Although it is understandable that the Tribunal did not appreciate that the applicant's case required a consideration of the 1971 Act, the way in which the alternative submission was put in closing submissions, namely that liability was attracted because Mr Hawkins was exposed to more cigarette smoke both directly through consuming more cigarettes and indirectly through passive smoking in the course of his employment, in my opinion sufficiently identified the issue as one that required consideration: see Grant v Repatriation Commission (1999) 57 ALD 1 at 5 – 6. 39 The evidence does not give detail of Mr Hawkins' work environment either in Darwin or in his last period at Pearce. However, the Tribunal has found that Mr Hawkins continued to smoke forty cigarettes per day during this period, and that his fellow signal operators with whom he worked smoked whilst on duty. From one source or another Mr Hawkins continued therefore to inhale cigarette smoke, and the Tribunal found on Professor West's evidence that the greater the exposure to smoking, the more likely it is that a person will die from smoking related illnesses, and that the greater the exposure to smoke, the more accelerated the disease will be. 40 The Tribunal fell into error of law in not considering the application of the 1971 Act. However, that alone is not sufficient to allow the appeal. It is necessary to consider whether on the evidence and the findings of fact it would have been open to the tribunal to make a finding in the applicant's favour. Unless that was open, the error of law is immaterial to the Tribunal's ultimate decision. If an error of law is immaterial to the decision, the appeal will be dismissed: see Hyundai Automotive Distributors v Australian Customs Service (1998) 51 ALD 45 at 55. 41 To succeed under the 1971 Act, it would be necessary for the applicant to satisfy the Tribunal that Mr Hawkins' employment was a contributing factor either to the contraction of the disease or to the aggravation, acceleration or recurrence of the disease. On the evidence, the disease of atherosclerosis would have been an established condition by 1971, and the continual ingestion of cigarette smoke by Mr Hawkins would have aggravated and accelerated that condition. The question is whether in those circumstances it can be said that Mr Hawkins' employment was a contributing factor to the aggravation and acceleration of his disease. 42 In Federal Broom Co Pty Ltd v Semlitch (1964) 110 CLR 626 the High Court considered the interpretation of s 6(1) of the Workers Compensation Act 1926 (NSW) which for practical purposes is in identical terms to s 29 of the 1971 Act. In that case the worker had a history of functional mental illness pre-disposing her to delusions. In the course of her work she dropped a tea chest which she had pulled from its position on top of other tea chests and, in trying to keep it from falling on her foot, she sustained a muscular strain in her right side. She sought worker's compensation in respect of a continuing incapacity resulting from a delusional condition following upon the physical injury. The worker suffered a delusion that she continued to be seriously affected in a way which made it impossible for her to work by reason of abdominal pain. In relation to the concept of employment as a contributing factor, Kitto J, in whose judgment Taylor and Owen JJ agreed said (at 632 – 3): "Where it is possible to identify as a contributing factor to the aggravation, acceleration, exacerbation or deterioration of a disease, some incident or state of affairs to which the worker was exposed in the performance of his duties and to which he would not otherwise have been exposed, I see no misuse of English in condensing the statement of the fact by saying simply that the employment was a contributing factor to the aggravation etc. It is in that sense that I should understand the language of the definition." 43 Windeyer J, dealing with the question of contribution by employment, said (at 641): "I pass then to the next, and I think more difficult, question, was this aggravation or deterioration contributed to by her employment? This requirement of the Act is not satisfied by showing only that a worker suffering from some disease would or might have suffered less severely if he had not been employed at all. When the Act speaks of 'the employment' as a contributing factor it refers not to the fact of being employed, but to what the worker in fact does in his employment. The contributing factor must in my opinion be either some event or occurrence in the course of the employment or some characteristic of the work performed or the conditions in which it was performed." 44 These passages from the High Court judgment were applied in the interpretation of s 29 of the 1971 Act by a Full Court of the Federal Court in Treloar v Australian Telecommunications Commission (1990) 97 ALR 321 at 327 – 328. At 328 the Full Court said: "In our opinion, it follows from what is said and, indeed, from what is not said in these passages and from a consideration of the plain words that once it is established that an employee in the doing of his work was exposed to 'a state of affairs to which he would otherwise not have been exposed' or to 'some characteristic of or condition in which the work was to be performed' and that such exposure was in truth a 'contributing' factor to the condition in respect of which he seeks compensation, then it matters not whether the contribution was of any particular size or degree. The same applies where the complaint is not one of initiation of the condition but of its aggravation, in the sense of making it worse, or its acceleration in the sense of speeding up the process of a progressive disease. In all cases the question is whether there has been a 'contribution'." 45 In my opinion it follows from these authorities that it is not sufficient that the circumstance that aggravates or accelerates a disease merely arises in the course of the employment. That conclusion is also supported by the concluding words of s 29 of the 1971 Act, namely the words "whether or not the disease was contracted or the aggravation, acceleration or occurrence was suffered in the course of that employment". In my opinion these words indicate that for the employment to be a contributing factor, the circumstance said to constitute the contributing factor must have a relationship to the nature of the employment similar to that which was required under s 10 of the 1930 Act. The characteristic or feature of the employment said to constitute the contributing circumstance must involve a tendency to bring about the contraction of the disease or the aggravation, acceleration or occurrence of it. It is for this reason that Kitto J in explaining the concept of employment as a contributing factor added the qualification that an incident or state of affairs to which a worker is exposed in the performance of his duties must be one to which he would not otherwise have been exposed. 46 In the present case the ingestion of smoke arising from Mr Hawkins own smoking would have occurred in any event. He was a persistent smoker. The fact that his employer did not prohibit him smoking during working hours is not sufficient, in my opinion, to render his employment a contributing factor to the aggravation or acceleration of his disease within the meaning of s 29 of the 1971 Act. 47 Insofar as the contributing factor is said to be passive smoking, the claim must fail on the evidence. On Professor West's evidence, the Tribunal was not satisfied that passive smoking equivalent to smoking one or two cigarettes each day caused or aggravated the atherosclerosis from which Mr Hawkins died. Moreover, the evidence of Professor West that the passive smoking was equivalent to smoking one or two cigarettes per day was based on the conditions described in the old building at Pearce. The evidence fails to disclose whether passive smoking to which Mr Hawkins may have been exposed after 1 September 1971 would have had any passive smoking effect. At best, on the evidence it might have had, but whatever the effect it would have been very much less than one to two cigarettes per day. 48 In my opinion, the applicant has failed to demonstrate that the failure of the Tribunal to consider the 1971 Act led to an erroneous decision. 49 Under this ground of appeal the applicant also argues that the Tribunal fell into error in its consideration of the passive smoking issue under s 9 of the 1930 Act. Under that Act injury was defined to include the aggravation and acceleration of a pre-existing injury. In a passage earlier cited from the reasons of the Tribunal, the Tribunal said that it was not satisfied that "Mr Hawkins passive smoking caused or aggravated the atherosclerosis from which he died". The applicant complains that the Tribunal failed to consider whether Mr Hawkins passive smoking accelerated the atherosclerosis. I do not accept that any error occurred in this respect. Whilst the Tribunal did not expressly exclude acceleration, I consider that when the reasons are read as a whole it is quite clear that the Tribunal was expressing a conclusion that the applicant had failed to satisfy it that the disease was either caused by the passive smoking, or met the alternative requirement that a "pre-existing injury" be aggravated or accelerated by it. The evidence of Professor West plainly embraced both the concept of aggravation and the concept of acceleration. 50 The applicant's written submissions also complain under this ground of appeal that the Tribunal failed to investigate the relationship of other medical conditions suffered by the applicant to his employment, including x-ray findings in 1990 consistent with long standing tuberculosis. There is no substance in this submission. The evidence fails to explain any basis upon which the other conditions could be relevantly related to Mr Hawkins' employment; the other conditions were not the basis of the claim before the Tribunal; and in any event the post mortem report did not confirm a diagnosis of tuberculosis. Ground C 51 The Tribunal was wrong in law in failing to apply the factual circumstances applicable to the employee with the requirement of the legislation. 52 This obscurely worded ground of appeal appears to raise in another form the issues canvassed under Grounds A and B. In considering the matter the Tribunal outlined the relevant provisions of the 1930 Act and at length sought to apply them to the facts. The Tribunal specifically addressed matters which are identified in the applicant's submissions under this ground, and in particular periods of social activities when smoking occurred, passive smoking tolerated in the workplace, and evidence that the work environment was perceived as stressful. Insofar as the Tribunal failed to apply the 1971 Act to the facts, that issue is covered by Ground B above. No error of law is demonstrated by Ground C. Ground D 53 The Tribunal was wrong in law by confusing the test causative, temporal to be applied in order to ascertain if the death of the employee was due to the nature of his employment. 54 Under this ground it is contended that the Tribunal erred in considering questions of causation when discussing whether Mr Hawkins' own smoking constituted personal injury by accident arising out of or in the course of his employment. Had there been any prospect on the evidence of establishing that by taking up smoking Mr Hawkins had suffered personal injury by accident, this submission could give rise to a relevant issue. However, for reasons earlier given that is not the case, and the ground of appeal discloses no error of law that bears on the correctness of the Tribunal's decision. Ground E 55 The Tribunal was wrong in law in failing to take into account activities associated with the employment because they were engaged outside normal hours. 56 Earlier in these reasons I have referred to the Tribunal's finding in the course of considering whether Mr Hawkins' own smoking was compensable under s 9 of the 1930 Act that the occasions on which the signal operators socialised were not merely intervals or interludes within an overall period or episode of work. Under this ground it is contended that the Tribunal was required to ask, but failed to ask whether smoking was part of the nature of the employment the deceased was engaged in. It is contended that it was open to the Tribunal to find on the material before it that the type of service conditions which included smoking continued outside the radio room and were therefore still within the nature of the employment of the deceased. In my opinion this submission fails for two reasons. First, even if it was open to the Tribunal to make such a finding on the evidence, the Tribunal was not satisfied that it should do so. The Tribunal's conclusion was open on the evidence, and accordingly the Tribunal made no error of law in making the finding which it did, even if other findings might also have been open. It is for the Tribunal to find the facts, and so long as it does so on available evidence, there is no error of law even if a reviewing court thinks it might have found the facts somewhat differently. Secondly the applicant's case failed, for reasons already given, to establish that the smoking environment at work justified a finding that Mr Hawkins atherosclerosis was due to the nature of his employment. A fortiori, smoking activities in a social environment away from the workplace do not meet the requirements of s 10 of the 1930 Act. The evidence about social activities was directed to events before the 1971 Act came into operation, but if it is suggested that the submission also extends to events after 1 September 1971, for the same reasons the ground of appeal must fail. Ground F and G 57 These grounds of appeal repeat the complaint that the Tribunal failed to consider whether under the 1971 Act there had been an aggravation, acceleration or recurrence of Mr Hawkins' disease. This complaint is dealt with above. Ground H 58 The Tribunal was wrong in law in failing to provide adequate and sufficient reasons pursuant to s 43(2B) of the Administrative Appeals Tribunal Act 1975. 59 Section 43(2B) provides that where the Tribunal gives in writing the reasons for its decision (which it did in this case) those reasons shall include its findings on material questions of fact and a reference to the evidence or other material on which those findings were based. Having regard to the long and detailed reasons which were published by the Tribunal, this submission is a surprising one. Section 43(2B) imposes on the Tribunal a similar obligation to that imposed on the Refugee Review Tribunal by s 430 of the Migration Act 1958 (Cth). That section obliges the Refugee Review Tribunal to prepare a written statement that does four things: "(a) sets out the decision of the Tribunal on the review; and (b) sets out the reasons for the decision; and (c) sets out the findings on any material questions of fact; and (c) refers to the evidence or any other material on which the findings of fact were based." 60 In considering the scope of the obligation imposed on the Refugee Review Tribunal by s 430(1) McHugh, Gummow and Hayne JJ in Minister for Immigration and Multicultural Affairs v Yusuf (2000) 75 ALJR 1105 at [67] – [68] said: "As was rightly observed in the joint judgment in Singh (2000) 98 FCR 469 at 480 [44], this section calls for a recording of matters that are matters of fact. In particular, s 430(1)(c) requires the Tribunal to set out the findings of fact which it made. But does it require more? Does it oblige the Tribunal to make findings on any and every matter of fact objectively material to the decision which it was required to make? Section 430 does not expressly impose such an obligation. In its terms, it requires no more than that the Tribunal set out the findings which it did make. Neither expressly nor impliedly does this section require the Tribunal to make, and then set out, some findings additional to those which it actually made. In Singh, significance was attached to the use of the word 'material' in s 430(1)(c). It was said that 'material' in the expression 'material questions of fact' must mean 'objectively material'. Even if that were right, it would by no means follow that the Tribunal was bound to set out findings that it did not make. But it is not right to read 'material' as providing an objective or external standard of materiality. A requirement to set out findings and reasons focuses upon the subjective thought processes of the decision-maker. All that s 430(1)(c) obliges the Tribunal to do is set out its findings on those questions of fact which it considered to be material to the decision which it made and to the reasons it had for reaching that decision." In the present case the Tribunal has eloquently set out its findings on the questions of fact which it considered to be material to the decision which it made and to the reasons it had for reaching that decision. The reasons are comprehensive and disclose why the Tribunal arrived at the particular conclusions that it did: see Dixon v Repatriation Commission [1999] FCA 582 at 14. In my opinion there has been no breach of the requirement imposed by s 43(2B) of the Administrative Appeals Tribunal Act 1975. Ground I 61 The Tribunal was wrong in law in the interpretation of the High Court decision of Haltzimanolis v ANI Corporation Ltd (1992) 106 ALR 611, Commonwealth v Bourne (1960) 104 CLR 32 and Connair Pty Ltd v Frederiksen (1979) 142 CLR 485. 62 No written or oral submissions have been advanced in support of this ground of appeal, and it is not apparent that the Tribunal made any error in its understanding of these decisions. Ground J 63 The Tribunal was wrong in law in not applying in the circumstances of the employee the decision of Treloar v Australian Telecommunications Corporation (1990) 12 AAR 535 [also reported at 97 ALR 321]. 64 This ground of appeal again raises complaint that the Tribunal failed to consider the application of the 1971 Act. Treloar v Australian Telecommunications Corporation is discussed above. I do not consider it assists the applicant. Ground K 65 The Tribunal was wrong in law in requiring the applicant to carry the onus of proof and failing to recognise the beneficial nature of the legislation. 66 In my opinion the Tribunal did not require the applicant to carry the onus of proof. The Tribunal simply concluded that it was not satisfied of the necessary relationship between Mr Hawkins' atherosclerosis and his employment. The beneficial nature of legislation may be a relevant factor where it is necessary to construe an ambiguous provision within the legislation. In the present case, however, no such construction question arises and the beneficial nature of the legislation is irrelevant to the issues which were presented to the Tribunal, and which arise on this appeal. 67 For these reasons I consider that the appeal must be dismissed. In accordance with the agreement between the parties there will be no order as to costs. I certify that the preceding sixty-seven numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice von Doussa Associate: Dated: Counsel for the Applicant: Mr D De Marchi Solicitor for the Applicant: Bill Piper Solicitor Counsel for the Respondent: Mr P Hanks QC and Ms E Ford Solicitor for the Respondent: Australian Government Solicitor Date of Hearing: 10 September 2001 Date of Judgment: 17 December 2001