The State of South Australia v Ellis - [2008] WASCA 200

JURISDICTION : SUPREME COURT OF WESTERN AUSTRALIA

TITLE OF COURT : THE COURT OF APPEAL (WA)

CITATION: THE STATE OF SOUTH AUSTRALIA -v- ELLIS [2008] WASCA 200

CORAM: MARTIN CJ
STEYTLER P
McLURE JA

HEARD: 12 - 14 FEBRUARY 2008
ON THE PAPERS 14 MAY 2008

DELIVERED : 26 SEPTEMBER 2008

FILE NO/S: CACV 11 of 2007
CACV 12 of 2007
CACV 13 of 2007

BETWEEN: THE STATE OF SOUTH AUSTRALIA
First Appellant
AMACA PTY LTD (ACN 000 035 512)
Second Appellant
MILLENNIUM INORGANIC CHEMICALS LTD (ACN 008 683 627)
Third Appellant
AND
TERESA ELLIS As Executor of the Estate of PAUL STEVEN COTTON (Dec)
Respondent

ON APPEAL FROM:
Jurisdiction              :  SUPREME COURT OF WESTERN AUSTRALIA
Coram  :EM HEENAN J
Citation  :ELLIS, Executor of the Estate of PAUL STEVEN COTTON (DEC) -v- THE STATE OF SOUTH AUSTRALIA & ORS [2006] WASC 270
File No  :CIV 2314 of 2000

Catchwords:

Employer's liability - Estate claim - Asbestos - Lung cancer - Death due to progressive lung cancer - Is lung cancer a divisible or indivisible disease - Employment in industry involving exposure to asbestos - Peak exposures to asbestos - Quantification of exposure - Latency - Two periods of employment - Relevance of separately evaluating the contribution made by each defendant - Material contribution - Causation - Deceased formerly a smoker - Tobacco smoking a significant cause of fatal lung cancer - Extent of exposure to asbestos in working environments - Relatively low levels of asbestos exposure - Potential cumulative effects of exposure - Potential interaction of tobacco smoking and exposure to asbestos fibres as multiplying the toxic effect of both substances - Acceleration of onset of lung cancer - Significance of early onset of cancer after exposure to asbestos in either workplace - Significance of statistical attempts to estimate harmful concentrations of asbestos fibres in working environments - Breach of employer’s duty - Superseding cause - Contributory negligence

Legislation:

Industrial Safety Code Regulations 1975 (SA), r 39(1), r 39(2), r 39(3), r 39(4)
Industrial Safety, Health and Welfare Act 1972 (SA)
Occupational Health, Safety and Welfare Act 1984 (WA)
Occupational Health, Safety and Welfare Amendment Regulations (No 2) 1991 (WA)
Occupational Health, Safety and Welfare Regulations 1988 (WA), r 103, r 322, r 801, r 803, r 804, r 808, r 815, r 816, r 823, sch 3

Result:

Grounds 1, 2, 3 and 5 of the appeal are dismissed

Ground 4 of the appeal is upheld and the reduction of 10% arrived at by the trial judge in respect of Mr Cotton's contributory negligence is substituted by a reduction of 50%

Category: A

Representation:

Counsel:

First Appellant              :     Mr G M Watson SC & Ms C J Thatcher
Second Appellant          :     Mr G M Watson SC & Ms J M Kubacz
Third Appellant            :     Mr G M Watson SC & Mr S J Rushton
Respondent:     Mr B W Walker QC & Mr J R C Gordon

Solicitors:

First Appellant              :     State Solicitor for Western Australia
Second Appellant          :     Minter Ellison
Third Appellant            :     Lavan Legal
Respondent:     Slater & Gordon

Case(s) referred to in judgment(s):

Amaca Pty Ltd v Hannell [2007] WASCA 158
Amaca Pty Ltd v Moss [2007] WASCA 162
Bendix Mintex Pty Ltd v Barnes (1997) 42 NSWLR 307
Bennett v Minister of Community Welfare (1992) 176 CLR 408
Bonnington Castings Ltd v Wardlaw [1956] AC 613
Chandley v Roberts [2005] VSCA 273
Chappel v Hart [1998] HCA 55; (1998) 195 CLR 232
Commonwealth of Australia v Ryan [2002] NSWCA 372
Daly v Liverpool Corporation [1939] 2 All ER 142
Dovuro Pty Ltd v Wilkins [2003] HCA 51; (2003) 215 CLR 317
Glasgow Corporation v Muir [1943] AC 448
Graham Barclay Oysters Pty Ltd v Ryan [2002] HCA 54; (2002) 211 CLR 540
Homestyle Pty Ltd v Perrozzi [2007] WASCA 16; (2007) 33 WAR 209
Joslyn v Berryman [2003] HCA 34; (2003) 214 CLR 552
Krakouer v The State of Western Australia [2006] HCATrans 581
Krakouer v The State of Western Australia [2006] WASCA 81
March v E & M H Stramare Pty Ltd (1991) 171 CLR 506
McHale v Watson (1966) 115 CLR 199
Monie v Commonwealth of Australia [2007] NSWCA 230
Mount Isa Mines Ltd v Pusey (1970) 125 CLR 383
Mulligan v Coffs Harbour City Council [2005] HCA 63; (2005) 223 CLR 486
Neindorf v Junkovic [2005] HCA 75; (2005) 80 ALJR 341
Owners of Steamship or Vessel 'British Fame' v Owners of Steamship or Vessel 'Macgregor' (The 'British Fame') [1943] AC 197
Podrebersek v Australian Iron and Steel Pty Ltd (1985) 59 ALJR 492
R v Franklin [2001] VSCA 79; (2001) 3 VR 9
Roman Catholic Church Trustees for the Diocese of Canberra and Goulburn v Hadba [2005] HCA 31; (2005) 221 CLR 161
Rosenberg v Percival [2001] HCA 18; (2001) 205 CLR 434
Seltsam Pty Ltd v Ghaleb [2005] NSWCA 208; (2005) 3 DDCR 1
Seltsam Pty Ltd v McGuiness [2000] NSWCA 29; (2000) 49 NSWLR 262
Tame v New South Wales [2002] HCA 35; (2002) 211 CLR 317
Vairy v Wyong Shire Council [2005] HCA 62; (2005) 223 CLR 422
Wilsher v Essex Area Health Authority [1988] AC 1074
Wynbergen v Hoyts Corporation Pty Ltd [1997] HCA 52; 72 ALJR 65
Wyong Shire Council v Shirt (1980) 146 CLR 40

MARTIN CJ:

Introduction

The appellants, the State of South Australia, Amaca Pty Ltd (Amaca) (formerly James Hardie and Coy Pty Ltd) and Millennium Inorganic Chemicals Ltd (Millennium) (formerly SCM Chemicals Ltd) appeal from a judgment entered against them in favour of Ms Teresa Ellis, in proceedings which she commenced against them in her capacity as the executrix of the estate of the late Paul Steven Cotton (Mr Cotton).
Each of the appellants was found liable on the basis that their breaches of duty had resulted in Mr Cotton being exposed to respirable asbestos fibre which caused, or materially contributed to, his contraction of lung cancer.
Mr Cotton was born in Adelaide, South Australia, on 6 October 1956. During his childhood, he lived with his family in a brick house in a suburb of Adelaide. There was no suggestion in the evidence that he experienced any particular exposure to asbestos fibres during his childhood or adolescence, beyond that exposure to which all members of an urban community are subject.
Mr Cotton left school at the age of 16, and commenced employment in a variety of capacities. At the age of 17 he took up smoking cigarettes. He smoked continuously for a bit over 26 years, until he was diagnosed with lung cancer in May 2000. The evidence, which the trial judge accepted, was to the effect that throughout this period, Mr Cotton smoked between 15 and 20 cigarettes per day. When the reasons of the trial judge are read as a whole, it is clear that references to 'half a pack a day' in those reasons should be taken to be references to half a pack of 30 cigarettes.
On 4 September 1975, Mr Cotton commenced employment with the Engineering and Water Supply Department of South Australia (EWSD). In the first 6 months of his employment he worked as a gardener and had no particular exposure to asbestos. However, from about March 1976, he worked as a member of a gang engaged in the laying of pipes made of asbestos cement manufactured by Amaca. Occasionally the gang would be engaged in repairs and maintenance work in respect of previously laid pipes. Mr Cotton worked in that capacity until 2 October 1978; that is, for a period of about 2.5 years.
After ceasing employment with EWSD, Mr Cotton worked in a variety of capacities in outback South Australia and the Northern Territory. He met Ms Ellis in the Northern Territory in about 1981. They formed a relationship and lived together in a de facto relationship until Mr Cotton's death. They had four children.
Mr Cotton lived with his family in Katherine in the Northern Territory until moving to Western Australia in 1989 or 1990. There is no evidence to suggest that he experienced any particular exposure to asbestos while living and working in the Northern Territory.
On 19 April 1990, Mr Cotton commenced work with Millennium. He worked for Millennium until 19 February 1991, when he was laid off because of lack of work. He resumed employment with Millennium on 14 October 1991 until 28 January 1993, when he was again laid off. However, he resumed work with Millennium shortly thereafter on 11 February 1993, and remained employed by Millennium until his death on 6 January 2002. As I have noted, his lung cancer was diagnosed in May 2000, when he was 43 years of age.
During Mr Cotton's employment with Millennium he was engaged in a variety of work. It will be necessary to review the evidence and findings in relation to the particular activities which he carried out during his employment with Millennium in some detail later in these reasons.
Mr Cotton commenced proceedings claiming damages for personal injury against each of the appellants prior to his death. Following his death, Ms Ellis was substituted as the plaintiff.
The causes of action relied upon against EWSD were negligence, breach of a term to be implied into the contract of employment (said to be co‑extensive with the duty of care imposed upon employers at common law) and breach of statutory duty. The same causes of action were asserted against Millennium. As against Amaca, the only cause of action relied upon was negligence, and in particular breach of Amaca's duty of care as manufacturer and supplier of the asbestos cement pipes upon which Mr Cotton worked while employed by EWSD. The trial judge found each cause of action against each appellant had been made out.
The appellants had each relied upon a variety of defences, including contributory negligence. Having found in favour of Ms Ellis in respect of the claims in contract against both EWSD and Millennium, the trial judge concluded that contributory negligence was not available as a defence to, or in reduction of, those claims. That conclusion is not challenged. However, in respect of the claim against Amaca, the trial judge upheld Amaca's contention that Mr Cotton had failed to take adequate care for his own safety, by smoking after being warned by a medical practitioner not to do so in 1992, and he reduced the claim against Amaca by 10% by reason of that contributory negligence.
The assessment of the damages awarded against each of the appellants was complicated by the different legal provisions applying to fatal accident claims in South Australia and Western Australia. However, as no issue is taken with the assessment of damages by the trial judge, it is unnecessary to traverse those issues or particularise the amounts awarded.

The reasons of the trial judge

The reasons of the trial judge occupy 354 pages. Their length reflects the complexity of the issues and the breadth of the evidence adduced, which included many reports and scientific articles. However, the sheer length of the reasons provided, combined with the fact that they were no doubt compiled during successive intervals between commitments to other judicial duties, has meant that there are inconsistencies between the findings made at different points in the reasons. I will identify those inconsistencies later.

The grounds of appeal

The grounds of appeal are expressed in general terms. Detailed written and oral submissions were advanced in amplification of the grounds, which challenged many of the findings of fact and conclusions of law at which the trial judge arrived. The length of the reasons given by the trial judge, the breadth of the evidence adduced at trial, and the breadth of the issues raised on appeal have each affected the time taken to give proper consideration to the issues, and the length of these reasons.
In these reasons I will deal firstly with the issues raised by the appellants in relation to the findings of fact made by the trial judge, and then with the issues they have raised in relation to the approach which the trial judge took to the legal issues.

The factual issues

I will deal firstly with the challenges made to the findings relating to Mr Cotton's employment by EWSD. Those challenges essentially relate to the findings made in respect of the composition of the asbestos cement pipes upon which Mr Cotton worked, in particular, the types of asbestos within those pipes when compared to other asbestos cement pipes which were the subject of tests and reports, and the amount of time per day during which Mr Cotton was engaged in tasks which exposed him to respirable asbestos fibre.

The composition of the pipes

As the trial judge found [66], asbestos occurs in different forms in nature. The three forms most commonly encountered are crocidolite (known as blue asbestos), amosite (known as brown asbestos) and chrysotile (known as white asbestos). Crocidolite and amosite are both forms of amphibole asbestos (being the name given to the type of rock from which they form). Chrysotile asbestos, on the other hand, is not an amphibole as it derives from serpentine rock. The amphibole forms of asbestos are now known to be significantly more toxic than the serpentine forms, and within the amphibole forms, crocidolite is known to be significantly more toxic than amosite. The amphibole forms of asbestos are also known to give rise to higher concentrations of respirable fibre when disturbed - such as when cut.
In relation to asbestos products (including asbestos cement) manufactured within Australia, the predominant source of crocidolite was the blue asbestos mine at Wittenoom. However, that mine closed in 1966, and generally speaking, the use of crocidolite within Australian cement products was phased out following the closure of that mine.
The trial judge dealt with the evidence relating to the composition of the asbestos cement pipes upon which Mr Cotton worked when employed by EWSD: [66] ‑ [78]. At [72] he refers to the report of an expert witness, Professor de Klerk, in which he referred to the type of asbestos in the pipes as having been likely to have been of mixed type. As the trial judge records, in oral evidence (ts 758), Professor de Klerk said that by referring to 'a mixed type' he meant that 'there would have been amosite and chrysotile and probably a little bit of crocidolite as well'.
However, Professor de Klerk is an epidemiologist and biostatistician. No evidence was given which would qualify him as having relevant expertise to advise on the likely composition of asbestos cement pipes manufactured and used in South Australia in the mid‑1970s.
On the other hand, as the trial judge notes [72], evidence with respect to the likely composition of the pipes was led from two occupational hygienists - Mrs Sowden and Mr Pickford. The trial judge found [285], Mrs Sowden has specialised in the occupational hygiene issues associated with exposure to asbestos for many years, and is well known and respected in that field. Mr Pickford is one of only 15 fellows of the Australian Institute of Occupational Hygienists [300] and, like Mrs Sowden, has specialised in issues arising from exposure to asbestos. The evidence of Mrs Snowden was that she had assumed that the asbestos content of the pipes would have been about 15% and that 10% ‑ 15% was a typical concentration. She further stated that the James Hardie pipes contained chrysotile and amosite. Mr Pickford, on the other hand, stated that the asbestos content was between 8% and 15%. Mr Pickford did not specifically mention chrysotile or amosite but noted that he doubted that any of the pipes contained crocidolite.
In the same paragraph of the trial judge's summary of Mrs Snowden's and Mr Pickford's evidence, the trial judge also comments on two documents. First, the mix specifications for James Hardie which state that the asbestos content of the pipes was between 13.42% and 14.92% (but the trial judge notes that the origins and purpose of that document was never clearly established). Second, a safety memorandum issued by EWSD which stated that asbestos cement types which the EWSD produced contained less than 20% asbestos.
The trial judge also referred to a report written in 1965 by Dr McCullagh, who was the medical officer employed by Amaca. In that report he referred to the use of crocidolite in the making of asbestos cement. However, that report, of course, predated the closure of the Wittenoom mine.
The trial judge summarised his conclusions in relation to the evidence in the following terms:
In combination with the writings of Dr McCullagh it seems probable, therefore, that the asbestos cement pipe used by the EWSD while Mr Cotton was working in its Adelaide operations included a variety of forms of asbestos, including Amosite, Chrysotile and Crocidolite.
In these circumstances I consider that the plaintiff has established, on the probabilities, that all the pipes produced by the second defendant and used by the first defendant for its water laying operations in and around Adelaide at the time Mr Cotton was employed by the EWSD contained mixed asbestos fibres making up between 15 per cent and 20 per cent of the entire composition of the asbestos cement product. The asbestos content was mixed and definitely included Chrysotile and Amosite and, probably, some Crocidolite [77] ‑ [78].
The trial judge gives no reasons for apparently preferring the unqualified assumption made by Professor de Klerk, and the historical report written by Dr McCullagh to the evidence of Mrs Sowden and Mr Pickford. During the appeal, counsel for the respondent accepted that the evidence adduced at trial did not sustain the finding that the new pipes laid by the EWSD between 1976 and 1978 and upon which Mr Cotton worked contained crocidolite (ts 250 ‑ 251). However, counsel for the respondent also pointed out that a small component of the work done by Mr Cotton for the EWSD involved repair of older pipes, and that it was possible that the older pipes may have contained some crocidolite. However, it is accepted that the work done by Mr Cotton repairing old pipes was a very small component of the work which he carried out (which was normally concerned with the laying of new pipes).
The trial judge repeated his erroneous finding to the effect that the new pipes upon which Mr Cotton predominantly worked while employed by EWSD contained crocidolite [118], [507], [509] in the latter two instances in a portion of his reasons which led to the conclusion that EWSD had made a material contribution to Mr Cotton's contraction of lung cancer. The trial judge also used the erroneous finding as a basis for diminishing the relevance and significance of two reports relied upon by the experts called by the appellants - referred to as the WAIT AID Study and the Amdel report. Each report was concerned with the measurement of the amount of respirable asbestos fibre released in the course of carrying out cutting work on asbestos cement pipes. The trial judge diminished the significance of those reports because the pipes that were tested did not contain crocidolite, whereas he had found (erroneously) that the pipes upon which Mr Cotton worked in South Australia did contain crocidolite: [250], [254]. The submission of the respondent to the effect that the error made by the trial judge was immaterial must therefore be rejected. It will be necessary to evaluate the significance of that error later in these reasons.
The trial judge made another error in respect of the composition of asbestos cement pipes. Again this concerned the composition of the pipes which were tested in studies relied upon by the experts called by the appellants. In relation to the Amdel study, the trial judge inferred that the types tested for the purposes of that report contained no amosite, because he could not detect a reference to amosite or crocidolite in the report of the study. There was no direct evidence to that effect. Moreover, the evidence of Mrs Sowden, which was not contradicted, was to the effect that asbestos cement pipes were never manufactured containing only chrysotile. The trial judge refers to that evidence, but proffers no reason for rejecting it in the context of that portion of his reasons dealing with the Amdel report.

Further, in evaluating the evidence given by Mr Kottek, an occupational and environmental health consultant called by the respondent, the trial judge observed:
Turning to his expression of opinion about the likely exposure of Mr Cotton to asbestos, Mr Kottek refers to measurements of asbestos contained in James Hardie documents referred to by Mrs Sowden as involving work in 1983 - 1984. That, therefore, is a reference to A/C pipe containing only Chrysotile which Mr Kottek expected would emit less dust than pipes containing Amosite and Chrysotile used by Mr Cotton at the EWSD in Adelaide [265].
Again, the trial judge gives no reason for concluding that the pipes worked upon in 1983 ‑ 1984 would only have contained chrysotile, when that conclusion is contrary to the direct and uncontradicted evidence of Mrs Sowden.
The appellants have established that the trial judge erred in respect of the findings he made in relation to the composition of the asbestos cement pipes upon which Mr Cotton worked while employed by EWSD, and in respect of the composition of the pipes used in some of the tests relied upon by the appellants' experts. The significance of those errors will be addressed later in these reasons.

The time spent cutting and rasping pipes

As the trial judge found, the work upon which Mr Cotton was predominantly engaged while employed by EWSD involved the laying of new asbestos cement pipes. Generally those pipes would be laid in trenches which had been cut in the ground. The pipes would be delivered to site, offloaded from the delivery truck, laid in place alongside the trench, and then joined in the trench. On occasions, because the length of the trench would not correspond exactly to the combined length of the pipes, or because a turn or an angle join was required, it would be necessary to cut the pipes. As the trial judge found, the actions of handling and joining the pipes did not, of themselves, give rise to significant quantities of dust, as the fibres in the pipes were not being significantly disturbed. However, dust, and therefore respirable fibre was created when the pipes were cut.
A number of methods were used for cutting the pipes during Mr Cotton's employment, including an angle grinder (very occasionally) or manual saws. However, the predominant method used was a chain cutter known as a Wheeler cutter, which involved a device which tightened a chain (which resembled the chain on a bike or a chainsaw) to a pressure which severed the pipe. After the pipe had been cut, it would usually be necessary to bevel the cut with a manual rasp in order to make a socket for the purposes of joinder to another pipe.
The activities of cutting and rasping were the activities which substantially gave rise to Mr Cotton's exposure to respirable asbestos fibre. There was controversy at trial as to the length of time generally occupied performing those tasks. As Mr Cotton had passed away by the time of the trial, he gave no direct testimony on this issue. However, statements he had previously made on the subject were tendered in evidence. In a statutory declaration, Mr Cotton described the process of cutting and rasping without making an estimate of the time taken. However, the transcript of evidence he gave in the course of worker's compensation proceedings before the Conciliation & Review Directorate of WorkCover was tendered in evidence. In the course of those proceedings, Mr Cotton asserted:
Well, doing the cut and all that used to take you about a half hour to an hour. It depended.
He went on:
MR COTTON:   You had this big long chain thing. You wrapped that around, and it went into a catch like that. It had a steel handle, and on the end there was a thing like a speedo on a motorbike. You could just keep winding it up, and as you did that the chain …
MR HADLOW:   It tightened the chain?
MR COTTON:   It tightens the chain up and cracks the pipe. As the pipe cracks, you give it a whack on the other end with the rubber hammer, and actually you've got a clean break.
MR HADLOW:   Then you'd do the filing?
MR COTTON:   Then you'd file off the taper.
MR HADLOW:   That process would take about …?
MR COTTON:   About an hour or an hour and a half.
MR HADLOW:   Altogether?
MR COTTON:   Yes.
MR HADLOW:   Okay. The filing: how much of that time would be spent between the cutting process and the filing process?
MR COTTON:   Most of the time you'd be doing your filing, because that was the bit you had to get out.
It does not appear that Mr Cotton was cross‑examined in relation to those assertions, which is not surprising, given that the worker's compensation proceedings were brought against Millennium, who had no particular interest in the work carried out by Mr Cotton for EWSD. However, it must be said that, on the face of it, it is surprising that a process of the kind described by Mr Cotton could take an hour or an hour and a half when applied to a pipe four inches in diameter.
Prior to his death, Mr Cotton swore answers to interrogatories administered by EWSD which were tendered in evidence. In those interrogatories he was asked to state the hours per day, days per week and weeks per year he spent working on the tasks he had identified in relation to the asbestos cement pipes. He replied that it was not possible for him to give any estimate of the time involved.
Shortly after being diagnosed with lung cancer, Mr Cotton consulted Professor Musk, a respiratory physician. Professor Musk reported that part of the history given by Mr Cotton included, in relation to the work done for EWSD:
This required the pipes to be cut and the ends rasped/filed to fit them together. This was done in the trenches for ten to twenty minutes three to four times a day. He would then continue to work in the trench where the filing had taken place.
In his reasons, the trial judge referred to the evidence given by Mr Cotton to the effect that the operation took 'about one to one and a half hours in total' [96], and also to his evidence that it 'would take half an hour to an hour' [97].
The trial judge referred also to evidence given by other employees of EWSD. In particular, he referred to the evidence of Mr Tilly, which was to the effect that:
[T]he actual chain cutter produced very little dust and could take only one or two minutes depending upon the size of the pipes being cut. With 6 inch or 8 inch pipes, once they had been cut, a file would be used to shape the ends and that may take eight or nine minutes and would generate lots of dust.
The trial judge referred also to the evidence given by other workers, including Mr Neagle and Mr Streater, although did not refer in his reasons to the evidence which they gave as to the time taken to undertake work of this kind. He did, however, state that he was:
[I]mpressed with the credibility and reliability of Mr Neagle and of Mr Streeter and, indeed, of all these former employees.
Mr Neagle's evidence was that cutting of the pipes was only occasional '[d]epending if you were going around the corner or you had to go and do a water drain or a T‑junction or a fire plug or a valve, you'd cut the pipes' (ts 225). He described the process of using the chain cutter to cut a pipe, and estimated that it would take 2 or 2 1/2 minutes (ts 226). He agreed that very little dust was generated in the process of cutting the pipe saying:
No, it was mainly chips because they made a jagged edge on the pipe, so it was chips that fell off, not actual dust.
He further estimated that the time taken to bevel the edge and 'grind the rebate' would take about 10 minutes (ts 242). He estimated that the cutting process would take place, on average, three times per day.
Mr Streater also described use of the chain cutter. He agreed that it was a method which resulted in very little dust being generated (ts 213), although if there was a burst main which had to be broken with a hammer, it seems more dust would have been generated.
Mr Campbell was another worker employed by EWSD who gave evidence. He said that cutting a pipe using a chain cutter 'probably took less than a minute' (ts 1039). He further estimated that it took between two and five minutes to hand rasp the end of a pipe once it was cut, depending on the size of the pipe. He observed that the rasp generated flakes and dust, but mainly dust (ts 1039). In his view, the whole process of cutting and rasping the pipe above ground would take five to six minutes, and laying and joining the pipe in the trench would take 30 to 45 seconds. Although Mr Campbell worked for EWSD after Mr Cotton's employment had ceased, there is no reason to suppose that the process described by Mr Campbell would have taken any longer to perform during Mr Cotton's time at EWSD.
The trial judge did not refer in his reasons to the time estimates given by Mr Neagle and Mr Campbell. However, he held:
During a typical working day Mr Cotton, or members of his gang, would usually be required to carry out a cutting operation on the four inch diameter AC pipes about twice, although this could be more frequent depending upon the particular design of the layout and connections required for the reticulation being installed. Despite different estimates of the times required for these tasks being given by witnesses operating on other crews and using slightly different methods, I consider I should accept the evidence of the deceased that these combined cutting and rasping operations, when required, would each last for about one to one and a half hours, meaning that two to three hours per working day would be occupied by those functions [119].
However, later in his reasons, he held, somewhat inconsistently:
However, there is little doubt in my mind that while Mr Cotton was working for the first defendant in Adelaide laying cement asbestos water pipes he was, on repeated occasions, subjected to a series of peak exposures to asbestos cement dust which were relatively short and transient but which occurred two or three times each working day for periods of something in the order of half an hour or more and, that at other times when working with the asbestos cement pipes, there was probably a significantly lower level of background exposure to asbestos fibres, but greater than occurs in a workplace where asbestos is neither used nor present [406].
The inconsistencies between the findings made in [119] and [406], make it difficult, if not impossible, to know precisely what the trial judge has found in respect of the amount of time during which Mr Cotton was customarily engaged in the tasks of cutting and rasping pipes while employed by EWSD. Further, his failure to refer to the evidence given by the other workmen who estimated the time likely to be taken, or to provide any reasons for rejecting that evidence, reinforce the concerns which arise from the apparently inconsistent findings. Further, as I have observed, the time estimates made by the fellow workmen appear inherently more probable than those made by Mr Cotton in the course of his evidence in the worker's compensation proceedings. I find it impossible to see how the tightening of a chain around a four‑inch pipe, and the bevelling of a cut made in the pipe by that process could take between an hour and an hour and a half.
Accordingly, I conclude that the findings made by the trial judge in respect of the amount of time spent by Mr Cotton in cutting and rasping pipes while employed by EWSD are flawed. The preponderance of the evidence establishes that the time taken to cut and rasp a pipe would be in the vicinity of 10 minutes, and that Mr Cotton would have been engaged in that exercise perhaps two or three times each day - that is, for a total of between 20 and 30 minutes each day. It follows that, depending upon whether one takes the finding at reasons [119] or the finding at reasons [406] to represent the findings of the trial judge, he has overstated the amount of time spent by Mr Cotton cutting and rasping the pipes while employed by EWSD by factors of six or three respectively.
This is not to say that Mr Cotton's only exposure to respirable asbestos fibre while employed by EWSD occurred while he was cutting and rasping the pipes. There was evidence that some dust was released by the general movement of the pipes, and to the effect that the material rasped or grinded off during the cutting process would simply be allowed to fall at the worksite, where, if disturbed, it could generate more dust, and therefore some respirable fibre. However, the view of all the experts was to the effect that exposures of this kind would be much smaller in magnitude than exposure during cutting and rasping, by several orders of magnitude.
Later in these reasons I will address the significance of the erroneous findings made by the trial judge in respect of the extent of Mr Cotton's exposure while cutting and rasping pipes during his employment with EWSD.

Exposure while employed by Millennium

The evidence in respect of the duties performed by Mr Cotton, the times at which he performed them, and the times at which asbestos materials were progressively removed from the worksite at Millennium was confusing and contradictory. Unfortunately, the findings of the trial judge have not resolved the confusion or contradictions.
Evidence was adduced of Mr Cotton's employment history with Millennium. The evidence took the form of a statement from Elizabeth Baggetta, the human resources manager of Millennium, which was tendered by consent without her being required for cross‑examination. That evidence was described by the trial judge as:
One of the few areas of certainty and lack of controversy in this regard is the history of Mr Cotton's employment classification with the third defendant.
The trial judge summarised that evidence at [125]. As he found, the employment records maintained by Millennium show that during Mr Cotton's first period of employment, between 19 April 1990 and 30 November 1990, he worked as a Plant Operator - Bulk Bag Packer, and from 1 December 1990 until 19 February 1991 as a Plant Operator - General Cleaning on day work in section 3 of the plant.
Section 3 is an area of the plant containing calciners and Raymond Mills/Crushing Rolls - it is separate from the band drier room (BDR) [128]. The BDR is closed off from section 3 [155].
During his second period of employment with Millennium, between 14 October 1991 and 28 January 1993, Mr Cotton initially worked as a Plant Operator in the Raymond Mill, and then as a Plant Operator‑Packer 4. He worked in those capacities between 14 October 1991 and 25 May 1992, when he commenced duties as a Plant Operator‑Packer 5. He continued to work in that capacity on various shifts until his employment was terminated on 27 January 1993. During Mr Cotton's third period of employment, from 11 February 1993 to 6 January 2002, he worked as a Plant Operator in the Research and Development section between 11 February 1993 and 8 August 1993, after which he resumed duties as a Plant Operator‑Packer 5 until October 1995. Thereafter he worked as a Plant Operator in the Shrink Wrap section until going on sick leave in March 2000.
The significance of these records, and their acceptance by the trial judge and the parties as providing an accurate record of Mr Cotton's employment, is that they establish the sections of the plant in which he was working at different times, and the duties he was performing. When those records are compared to Mr Cotton's recollection of the times at which he worked in different parts of the plant and performed differing duties, it is clear that those recollections were inaccurate. This is hardly surprising, as the evidence he gave in that regard occurred during worker's compensation proceedings which took place 8 or 10 years after the relevant periods, being the periods prior to the removal of the bulk of the asbestos materials from the Millennium worksite. The same observation may be made in respect of the evidence given by other employees of Millennium, which understandably, did not establish with specificity the precise periods during which Mr Cotton worked in different areas of the plant.
The evidence was to the effect that workers employed at Millennium, including potentially Mr Cotton, were exposed to respirable asbestos fibre from three potential sources of asbestos material. Most of those sources were located in an area of the plant known as the BDR. This was a large shed‑like area of the plant, approximately 200 ‑ 250 m in length, which contained a long oven, colloquially described as a large pizza oven, in which titanium dioxide, which was the material processed at the plant, was dried on a conveyor belt.
The first potential source of asbestos was the insulation associated with the pipes. Heat for the drying process was supplied through hot water pipes, which were insulated with a lagging material which included asbestos. This lagging material had been installed decades earlier, and was deteriorating, as a result of which chunks of the material were falling to the floor. Material which fell to the floor in this way would be swept up as part of the normal cleaning operations within the BDR. A second potential source of asbestos was the asbestos insulating material used within the doors to the oven, and on the exterior seals to those doors. This insulating material was also in a deteriorating condition and apparently released dust when the doors were removed which occurred periodically when the oven was cleaned. The third potential source of asbestos within the BDR was the roof, which was described as fragile and friable, and which was said to release dust from time to time. There were also areas of the plant which had walls which contained asbestos, but the evidence was consistently to the effect that these are unlikely to have been a significant source of respirable asbestos fibre.
The general effect of the evidence was that the activity which is most likely to have produced significant amounts of respirable fibre was the action of sweeping up lagging material which had fallen from the heating pipes in the BDR. Mr Cotton's evidence was to the effect that while he worked as a Plant Operator-Packer 5, after he had completed his work in the research and development department, he was required to enter the BDR from time to time, and to carry out cleaning duties in that room. On some of those occasions, he was engaged in the removal of the oven doors. His evidence, accepted by the trial judge, was that sometimes he went into the BDR three times per week, although sometimes he was only required to enter the room once a month. His evidence, in the worker's compensation proceedings, was to the effect that he had swept up the floor in the BDR about 15 or 20 times during the 12 month period prior to the removal of the asbestos lagging from the pipes in that area.
The trial judge reviewed the evidence given by a number of Millennium employees in respect of the removal of asbestos material from the work site. Mr Savage was one such witness, who was described by the trial judge as:
[A]n absolutely truthful, precise and reliable witness. He was the epitome of an intelligent, experienced, trustworthy senior tradesman.
His evidence was to the effect that the lagging on the heating pipes was partly removed in November 1991, and the remainder by March 1992.
Evidence to the same effect was given by Mr Forrester who was described by the trial judge as:
[A] careful, measured and precise witness who gave thoughtful and intelligent evidence with a good recollection of events.
Mr Forrester also accepted that the lagging material on the insulation pipes in the BDR was removed between November 1991 and March 1992.
Evidence was also given by Mr Ligman, who had been the day supervisor at the Millennium plant. He described the activities that were carried out in various sections of the plant. The effect of his evidence, which was summarised and apparently accepted by the trial judge, was to the effect that while Mr Cotton was working as a Plant Operator - Bulk Bag Packer or a Plant Operator‑Packer 4, involved in shrink‑wrapping or when working in the Raymond Mill, he would not have been required to attend the BDR: [213] and (ts 1491 ‑ 1492). Mr Ligman accepted that while Mr Cotton worked on day work for two and a half months in section 3 (December 1990 - February 1991), he may have been required to clean up the BDR occasionally (ts 1497). This evidence is consistent with the evidence of other employees, who recalled Mr Cotton performing clean up duties in the BDR before the asbestos lagging was removed from the heating pipes. However, when he was working as a Plant Operator‑Packer 5, Mr Cotton's duties would have required him to attend the BDR for clean‑up operations a couple of times a month (ts 1493). The trial judge therefore accepted [215] that while employed as a Plant Operator‑Packer 5, Mr Cotton would attend the BDR 15 to 18 times a year for about four to eight hours at a time. This evidence was consistent with Mr Cotton's evidence during the worker's compensation proceedings. By reference to the employment records provided in the statement of Ms Baggetta, to which I have referred, the trial judge found [213] that Mr Cotton commenced duties which would have required his occasional attendance in the BDR on 26 May 1992.

Evidence was also given by a Mr Engebretsen, who was the assistant maintenance superintendent at Millennium. The trial judge quotes:
I found Mr Engebretsen to be a careful and precise witness who was trying to be accurate and who gave evidence truthfully on matters within his direct knowledge [209].
His evidence, which the trial judge summarised at [196] ‑ [209] was to the effect that contractors (KBE) were engaged to remove the lagging from the heating pipes in the BDR in 1991, and that about half of the work was done in 1991, and then completed in March 1992.
After summarising all the evidence given in respect of removal of asbestos material from the Millennium plant, the trial judge set out a chronology listing the findings that he made in respect of that process [236]. Included within that chronology are the following entries:
November 1991 - about 50 per cent of the asbestos lagging from steam pipes in the BDR removed.
27 November 1991 - During annual shutdown KBE Contractors removed all the asbestos lagged pipe work in the boiler house and approximately 50 per cent of the asbestos lagging in the BDR …
…
March 1992 - Asbestos removal of lagging from pipes in BDR completed by KBE Contractors.
So, the trial judge found, consistently with the uncontradicted evidence, that contractors had removed all the lagging which contained asbestos material from the heating pipes in the BDR by March 1992. He had also found, consistently with the uncontradicted employment records, and the evidence of Mr Ligman, that Mr Cotton's regular duties in the BDR did not commence until he commenced work as a Plant Operator‑Packer 5 in May 1992 - that is, two months after all the lagging material in the BDR had been removed from the heating pipes. However, there was evidence (not specifically referred to in the reasons of the trial judge) that during the two and a half months Mr Cotton worked on days in section 3 (in late 1990, early 1991), he may have performed cleaning duties in the BDR.
However, the trial judge also accepted the evidence given by Mr Cotton in the worker's compensation proceedings [154]. He summarised that evidence, and the findings which he made in reliance upon it as follows:
The general tenor of Mr Cotton's evidence, without being precise, is that what are known as areas 1, 2 and 3 and the packing end were in close proximity to the BDR, although the BDR was closed off from them. Similarly, it appears from his evidence that his role as a shift work process operator, packer working in section 3 must have begun in January or February 1992 and that it was from then on that he began working regularly in the BDR. He said that this was about 12 months before the asbestos removal programme began in the BDR [155].
It will immediately be seen that these findings cannot stand with the other findings made by the trial judge, based on the uncontradicted evidence, as to the times at which the asbestos lagging material on the steam pipes in the BDR was removed, and the time at which Mr Cotton commenced duties in that room. It is clear from those findings that Mr Cotton's requirement to attend the BDR 15 ‑ 18 times per year did not commence until May 1992, by which time the asbestos lagging material on the heating pipes had been removed. Further, the evidence of Ms Baggetta, which the trial judge accepted as providing '[o]ne of the few areas of certainty' was to the effect that Mr Cotton worked in section 3 between 1 December 1990 and 19 February 1991. He cannot therefore have started in that section in January or February 1992. There was evidence that during the two and a half months Mr Cotton was working in section 3, he would have been required, on occasions, to perform cleaning duties in the BDR. It follows that the trial judge erred in finding that Mr Cotton had been engaged in duties in the BDR which included sweeping up asbestos material which had fallen from the lagging on the heating pipes for a period of 12 months before that material was removed.
The trial judge returned to his findings in relation to Mr Cotton's exposure to respirable asbestos fibre while employed by Millennium during that portion of his reasons dealing with liability. In that context he found:
The asbestos removal programmes conducted began with the asbestos lagging on the pipes in the BDR during 1991/1992 but did not involve the removal of all asbestos from the BDR, leaving the insulation and seals on the band drier hatch doors, other lagging on the top of the BDR and, of course, the asbestos cement roofing which was old and in a friable and deteriorating condition. The removal programmes to eliminate those further asbestos components in the BDR again took place in stages (during shut downs or maintenance periods) over the years from 1990 to April 1995 and the roof removal was not completed until late 1997. Removal of the asbestos cladding on the walls, internal walls and roofing in the packing areas and in which Mr Cotton was also employed was not completed until about 1998 [206].
During these periods there was an ever present risk of exposure to asbestos dust and, in Mr Cotton's case, particularly during sweeping up operations. In the time that he was working periodically in the BDR from the second half of 1991 until late 1992 he was sweeping up the dust from the floor which contained the fragments and shedding from the exposed lagging containing Chrysotile, Amosite and Crocidolite on the steam pipes and was, as I have found, exposed to short-term, but regular, high peak exposures of asbestos containing Chrysotile, Amosite and Crocidolite. No efforts were taken to avoid this, to conduct dust suppression by wetting or other methods or to provide protective equipment to the men working on those tasks. Again, the danger of development of any asbestos disease, including mesothelioma, was clearly patent and the failure to take steps to minimise this was, in my view, in breach of duty by the third defendant towards Mr Cotton. The question in this case is whether it caused to a material degree his fatal disease. [634] ‑ [635]
The finding that Mr Cotton was working periodically in the BDR from the second half of 1991 until late 1992 sweeping up dust from the floor which contained fragments and shedding from the exposed lagging cannot stand with the findings earlier made in relation to the time at which the lagging was removed, and the time at which Mr Cotton commenced duties in the BDR, which was at one point held to be January or February 1992 [155] and elsewhere in May 1992 [125], [213].
This is not to say that Mr Cotton was not engaged on occasional duties within the BDR after May 1992 which would have exposed him to respirable asbestos fibre. The trial judge found, consistently with the evidence, that the sealing material on the oven doors in the BDR was not removed until December 1994 and that further work of that kind was carried out in January 1995. Accordingly, on intermittent occasions while employed as a Plant Operator‑Packer 5, Mr Cotton would have carried out work removing the oven doors on the relatively infrequent occasions when the oven was shut down for cleaning purposes. He would also have received some exposure on the occasions he did cleaning up work in the BDR over two and a half months in late 1990, early 1991.
The other prospective source of respirable asbestos fibre was the roof in the BDR, and the sheeting walls in that room and other parts of the plant. Although the roof in the BDR was described as friable, and shedding dust, the experts generally accepted that while the roof was not disturbed, it was unlikely to have been a source of substantial quantities of respirable fibre. That evidence is consistent with the evidence of membrane filter sampling undertaken by consultants engaged by Millennium over a lengthy period commencing in 1988, prior to the commencement of Mr Cotton's employment at Millennium. The reports of that sampling, which were tendered in evidence, did not reveal any occasion upon which respirable asbestos fibre was present in sufficient quantities to be detected. It should be noted that between 1988 and 1995, the BDR was not tested as part of the sampling. However, during the removal of the asbestos sheeting, which took place in March 1995 [201], sampling was undertaken in the BDR and still did not detect sufficient quantities of respirable asbestos fibres. This would have been the period during which the roof was most 'disturbed' and therefore the height of potential for the release of respirable asbestos fibres. Further, precautions were taken during the removal period to warn staff about the asbestos removal and to limit staff access to the area. The area was cordoned off, and tape erected to prevent workers from moving under the area where the roof was being replaced.
Mr Cotton's evidence in the worker's compensation proceedings, accepted by the trial judge, was that while this work was going on, he was working in shed 4, which was about 70 feet away from the area in which the work was being carried out. Accordingly, while it is possible that some of the fibre disturbed by the work being carried out on the roof travelled to the area in which Mr Cotton was working, it seems unlikely that his exposure was extensive. That inference is supported by the finding made by the trial judge in relation to the air sampling carried out by contractors engaged by Millennium while asbestos removal activities were taking place. The trial judge found:
The pattern of sampling revealed by the second and subsequent series of analysis reports strongly suggests that this was sampling conducted in areas where contractors were actually removing asbestos, rather than an overall continuous planned estimation of airborne asbestos risks within the plant as a whole. There is no doubt that this system of air sampling was extensive and that it indicated that the airborne asbestos concentration at the areas sampled was low, and below the norms accepted for industry at the time. However, because of the nature and location of the sampling, it does not reveal the conditions in the BDR at the time Mr Cotton was working there and does not reveal anything about potential peak loads of airborne asbestos during operations such as sweeping up or cleaning in the BDR or, for that matter, in the packing sheds at the time of the removal of the asbestos cement roof sheeting. Nevertheless, it does show that during the periods when it was conducted and in other areas of the plant, the general level of airborne asbestos contamination was very low [310].
As I have already stated, the observations made by the trial judge in respect of Mr Cotton's work sweeping up and cleaning in the BDR must be read subject to his erroneous conclusion that there was still asbestos material lagging the heating pipes when Mr Cotton carried out that work from 1992 onwards. Read with that significant qualification in mind, the findings of the trial judge to the effect that the general level of airborne asbestos contamination in the plant was very low is significant. The trial judge then reviewed evidence of other sampling undertaken in the plant and concluded:
Nothing in those sample results alters the general impression that, when and where tested, the analysis results revealed the very low levels of airborne asbestos [311].
It is clear from this review of the evidence relating to Mr Cotton's exposure to respirable asbestos fibre while working at Millennium that the trial judge erred by finding significantly greater exposure than was sustained by the evidence.

Peak exposures

At many points throughout his reasons, the trial judge made reference to 'peak' exposures experienced by Mr Cotton while undertaking particular activities - such as cutting and rasping the asbestos cement pipes while employed by EWSD or (erroneously) while sweeping asbestos lagging material from the floor of the BDR ([255], [257], [271], [273], [288], [301], [319], [332], [333], [372], [385], [406], [409], [499], [518], [561], [562], [614], [617], [622], [624], [628], [630], [635]). Although it is, of course, necessary to estimate the level of exposure while particular activities are carried out for the purposes of assessing either a time weighted average or the total cumulative exposure during a particular period of employment, the language used by the trial judge when referring to peak exposures suggests that he concluded that concentrated exposure to fibre over small periods was somehow more toxic than sustained exposure to smaller levels of fibre over longer periods - see for example [333], [385]. The trial judge held:
Indeed, the writings and opinions which I have examined acknowledge the potential toxic effect of asbestos even at low doses (including the Helsinki Protocol); they acknowledge that short-term peak doses less than the long‑term average, especially if they exceed more than 10 fb/ml may be very harmful [518].
Similarly, the trial judge held:
I do not consider that demonstrating, even if it could have been demonstrated in this case, that Mr Cotton's average level of asbestos exposure calculated over an eight hour day was less than the prescribed maximum exposure levels by the applicable regulation in force at the time, demonstrated the exercise of reasonable care if, in addition, the fact of the matter is that he was exposed to regular but transient short periods of high level exposure in an uncontrolled operation involving sweeping up of dust containing asbestos particles including Amosite and Crocidolite and when it was known that he was an habitual smoker [622].
Further, the trial judge held:
The literature referred to in [528] of these reasons specifically mentions that it is not only the average long-term exposure which needs to be controlled but that even short-term exposures of 10 minutes or so of 10 fb/mls or above should be avoided. Consequently, I am unable to accept the submissions advanced by the defendants in this case that, if it could be concluded that Mr Cotton's exposure was less than the maximum exposure levels stipulated by applicable regulations at the relevant times, that would exclude any finding of lack of reasonable care [624].
The reference in that paragraph to [528] of the trial judge's reasons is erroneous because that paragraph is concerned with the evidence relating to the age of onset of lung cancer. It seems likely that the trial judge was intending to refer to [499] of his reasons:
Writing in the annals of occupational hygiene in 1970, an officer of the Factory Inspectorate Department of Employment in London, S Luxon (Exhibit 72(52)) discussed the then new asbestos regulations which came into effect in May 1970 and propounded that attempts to control asbestos dust should aim for a level of 2 fb/ml and 0.1 mg per ml for Chrysotile asbestos and spoke of the new methods of atmospheric testing then introduced, as proposed by the British Occupational Hygiene Society in 1968. However, he wrote that despite the adoption of those long-term average air concentrations, one should not ignore entirely peak concentrations and that in his view it seemed reasonable to accept that a concentration of, say, 12 fb/ml should not be exceeded during any period of 10 minutes. He went on to write:
'It must be remembered that we are using the fibre count not as an absolute measure of concentration but rather as a conveniently measurable parameter to indicate the total asbestos in the air. The work leading to the formulation of the BOHS Standard referred to above related to conditions in the textile industry and not enough information is yet available on the relationship between mass of asbestos and fibre counts in other industries. To further complicate the problem, it is not known what fibre sizes are biologically active and, even if this were known, appropriate elutriation (ie the rejection of material not biologically active) would be very difficult with a fibrous material such as asbestos. We ourselves are making both fibre counts and total mass determinations by X-ray diffraction analysis in industries, such as the motor industry, where degradation of the fibres may occur, resulting in a substantial change in size distribution.'
This appears to be the only support in the evidence for the proposition that peak concentrations of fibre carry greater dangers than sustained lower level exposures. It seems that the trial judge may have wrongly transposed the reference to 12 fb/ml to 10 fb/ml. The suggestion comes from an officer of the Factory Inspectorate Department of Employment in London, in a paper written in 1970. The qualifications of that officer for the expression of that view are not apparent. It is not a view which was endorsed by any of the experts called to give evidence in the case. Counsel for the respondent conceded during the hearing of the appeal that it is not a view which can be sustained as a matter of logic (ts 266). That is because the expert evidence is uniformly to the effect that it is the inhalation of respirable fibre into the lung which causes the potential for injury. While the quantity of fibre inhaled is relevant to the risk of injury being sustained, there is no logical reason why the inhalation of a particular quantity of fibre over a short period should carry any greater risk of harm than the inhalation of the same quantity of fibre over a longer period. The risk of disease is related to the amount of fibre retained by the lung, not the rate at which it is ingested.
The erroneous emphasis given by the trial judge to the significance of peak exposures appears to be responsible for another flaw in his process of reasoning which is evident in [614] of his reasons:
The evidence of concentrations which I have found probable, while admittedly estimating transient and relatively short-term peak exposures, are in excess of the maximum exposure limits recommended by the authorities. Accordingly, there is no basis for the first or second defendant to claim that the exposure levels associated with the work in Adelaide were at, or below, levels of exposure then thought acceptable because of the absence of sampling or objective testing.
The flaw in this reasoning is that the exposure standards recommended by authorities such as the National Health and Medical Research Council, and imposed by regulatory authorities, are all expressed by reference to time weighted average exposures, and not by reference to peak exposures. Accordingly, the only way in which compliance with those recommendations or regulations can be measured is by estimating time‑weighted average exposure over the entire working period, and not by reference to short‑term peak exposures only.

Quantification of Mr Cotton's exposure

The appellants challenge the findings made by the trial judge in respect of the attempts made to quantify the extent of Mr Cotton's exposure to respirable asbestos fibre while employed by EWSD and Millennium. A number of expert witnesses, predominantly occupational hygienists, gave evidence of their attempts to quantify Mr Cotton's likely exposure to respirable fibre during the course of his employment. They relied to differing degrees upon reports and studies dealing with the amount of respirable fibre produced when undertaking activities which were said to be comparable (in differing degrees) to the activities undertaken by Mr Cotton. The trial judge used findings which he made in respect of the limited relevance of some of those studies and reports to diminish the weight of the evidence given by the experts called by the appellants. Therefore, it is necessary to commence with a consideration of his findings in relation to those studies and reports.

The WAIT AID Study

The WAIT AID Study was commissioned by Amaca in 1983. A consulting firm associated with a tertiary education institution was engaged to assess the amount of respirable fibre released in the course of installing mains water pipes in a suburb of Perth.

As the trial judge found:
The reports observed that the dust from the pipes was only noticed during the machining of the cut pipe ends and that no other operation produced noticeable dust. Most of the day's work involved laying of the pipes, some time was spent bringing pipes to the trench. About one hour was spent performing three cuts on pipes and subsequent machining. The total machining time was about 30 minutes. It was also observed that dust from the machining of the cut pipe ends could be reduced considerably if the pipe end was kept wet during the machining process …
All of the tests conducted showed results of less than 0.1 fibres per ml of asbestos. The evidence does not disclose what type of asbestos fibre was in the particular pipes and it seems that only cutting involving the Wheeler cutter and a hammer and chisel were tested and that there was no sampling of machining or rasping of concrete pipe ends conducted, although Dr Nedved appears to have observed that the practice of using a field lathe (manual) was seen to produce visible dust and swarf (Exhibit 153(4)) [246] ‑ [247].
The conclusions drawn by the trial judge with respect to the comparability of the work the subject of the WAIT AID Study to the work undertaken by Mr Cotton were:
I have considerable reservations in accepting the WAIT AID Reports as being indicative of working conditions experienced by Mr Cotton in Adelaide from March 1976 until October 1978 because the tests do not indicate that they were conducted during periods when rasping and filing of the edges of cut pipe was being undertaken. Another significant difference is that the AC pipe then in use by the contractors participating in the test did not contain any component of Crocidolite, whereas the evidence is that there was Crocidolite in the AC pipes in use in Adelaide. Other evidence suggests that Crocidolite is considerably more noxious than Amosite or Chrysotile. Nevertheless, the WAIT AID tests do provide a basis for the first and second defendants' submissions that work involving the cutting of AC pipes in the open with Wheeler pipe cutters only produces a very low level of airborne asbestos fibre contamination [250].
The trial judge was correct to observe that the work the subject of the WAIT AID Study did not appear to include rasping and filing of the edges of cut pipe. However, it did appear to include the machining of the cut ends of pipe although apparently during at least some of the work, the pipe ends were kept wet during the machining process [246].
The other reason given by the trial judge for diminishing the relevance of the WAIT AID Study is his conclusion that the pipes the subject of that study did not contain any component of crocidolite, whereas the pipes upon which Mr Cotton worked in South Australia did contain crocidolite. For the reasons I have given above, that conclusion is erroneous. Nevertheless, the general conclusion by the trial judge to the effect that the study supported the proposition that the cutting of asbestos cement pipes in the open with Wheeler pipe cutters only produces a very low level of airborne asbestos fibre contamination is plainly justified by the study.
Despite that finding, the trial judge was not prepared to accept that the WAIT AID Study provided any reliable indication of the extent of Mr Cotton's exposure to respirable fibre while working for EWSD: [293], [317], [368], [408]. This rejection of the relevance of the WAIT AID Study was also relied upon to sustain his rejection of the evidence given by witnesses called on behalf of the appellants, including Mrs Sowden and Mr Rogers, to whose evidence I will refer in due course.
One of the reasons relied upon by the trial judge to reject the relevance of the WAIT AID Study is erroneous. While the relevance of that study is diminished by the differences in the work undertaken for the purposes of that study when the pipes were machined while damp (when compared to the work undertaken by Mr Cotton rasping the ends of dry pipe manually), in my view, the trial judge was wrong to conclude that this difference deprived the WAIT AID Study of any relevance, and did not sustain his conclusion that the evidence of Mrs Sowden and Mr Rogers had no weight.

The Amdel Report

Amdel is the trade name of an industrial scientific and laboratory service [251]. In 1984, Amdel conducted a study of the exposure to respirable asbestos fibre experienced by workers engaged in the preparation, cutting, trimming and installation of a typical building site drainage system in Queensland. The test was conducted over two consecutive days. On the first day of the test, the cutter used to cut the asbestos cement pipe was a Wheeler cutter, of the kind used by Mr Cotton in South Australia. On the second day of the test, an electric saw fitted with a water lubricated diamond cutting disk was used for all cuts [252]. As the trial judge found:
All the sample results obtained indicated an operating exposure lower than the then current NHMRC recommended threshold limit value for chrysotile of 1 fb/ml - in fact the results were less than 0.1 fb/ml, that is one‑tenth of the then current recommended threshold [253].
The conclusions drawn by the trial judge in respect of the comparability of the work undertaken for the purposes of the Amdel Report, and the work undertaken by Mr Cotton when employed by EWSD were:
Again, there are some differences between the process involved when Mr Cotton was employed by the second defendant in Adelaide and the operations tested by Amdel in Brisbane in 1984. Firstly, the appearance is that the pipes used in the process at Brisbane for the Amdel testing contained only Chrysotile for there is no report revealing any Amosite or Crocidolite being detected. Secondly, the manual rasping of the cut ends of the pipe which was observed and tested (not specifically addressed in the WAIT AID Report) involved the use of a particular rasp and a damp sponge - presumably because of the then known risk of airborne fibre generation from dry manual rasping. No such precaution was followed by the first defendant at the time Mr Cotton was employed in Adelaide and it is, therefore, likely that asbestos fibre generation from that process during his employment was greater than detected in the Amdel testing. Again, however, the Amdel Report does provide a basis for the first and second defendants' submission that the likely exposure to asbestos fibres from working and cutting with asbestos cement water pipe in the field was relatively low [254].
For the reasons I have already given, the inference drawn by the trial judge to the effect that the pipes used for the purposes of the Amdel Report contained only chrysotile is contrary to the uncontradicted evidence of Mrs Sowden (ts 1121). Accordingly, the first ground upon which the trial judge diminished the relevance of the Amdel Report is erroneous. The trial judge was correct to observe that the use of a damp sponge in conjunction with the manual rasp was a point of distinction between the work undertaken by Mr Cotton and the work the subject of the Amdel Report.
However, as the trial judge found in the paragraph set out above, that distinction did not deprive the Amdel Report of all relevance. As he found, the Amdel Report provided a basis for the proposition that Mr Cotton's likely exposure to asbestos fibres as a result of working and cutting asbestos cement water pipe in the field was relatively low.
However, despite that finding, in later portions of his reasons [293], [301], [317], [368] and [408], the trial judge proceeds on the basis that the Amdel Report, like the WAIT AID Study, is of no relevance whatever, and uses that conclusion to give no weight to the evidence given by Mrs Sowden and Mr Rogers. In my respectful opinion, he was wrong to do so.

The Kumagai Study

A study undertaken in 1993 in Japan (referred to variously by the trial judge as the Kumagai Study or the Japanese study) was the subject of an extract in the Japanese Journal of Independent Health which was tendered. The study reported upon repair operations conducted in water mains constructed of asbestos cement pipe in which the asbestos material included 15% ‑ 20% of chrysotile or crocidolite [261]. Due to the trial judge's erroneous conclusion that the pipes upon which Mr Cotton worked while employed by EWSD included crocidolite, the trial judge failed to identify the fact that the inclusion of that material in the pipes, the subject of the Japanese study, was a significant point of distinction between the work the subject of that study and the work undertaken by Mr Cotton. That is because, as the trial judge found, crocidolite is known to generate greater amounts of dust when cut than other forms of asbestos.
There were other significant points of distinction between the work the subject of the Japanese study and the work undertaken by Mr Cotton. For the purposes of the Japanese study, high speed power cutting tools were used in confined areas. The uncontradicted evidence was to the effect that the use of such tools, in a confined space (as compared to the open areas in which Mr Cotton worked) was likely to produce much greater quantities of respirable fibre than that experienced by Mr Cotton.
It is clear that the points of distinction between the work undertaken for the purposes of the Japanese study, and the work undertaken by Mr Cotton, were much more significant than the points of distinction involved in the WAIT AID Study and the Amdel Report. Nevertheless, the trial judge concluded that the Japanese study provided a more reliable guide to the likely levels of exposure experienced by Mr Cotton than the WAIT AID Study and the Amdel Report: [303], [317]. In my respectful opinion, he was wrong to do so.

The A/C Pipe Producers Association Report

A report prepared for the Asbestos Cement Pipe Producers Association of Arlington, Virginia in 1977 relating to dust exposures during the cutting and machining of asbestos cement pipe was tendered in evidence. The conclusions drawn by the trial judge from that report were:
The tests conducted and reported upon by the A/C Pipe Producers Association of the USA appear to me to be more comprehensive and representative than either of the tests conducted by WAIT AID or Amdel and, significantly, they recognised the phenomenon of peak exposure loads during intensive parts of the daily operation. Again, however, they do not report upon the type of asbestos fibres in the sources, or in the air samples, but the overall tenor of the report, in common with the Amdel and WAIT AID reports is that airborne asbestos contamination from these type of operations was regarded as being low, although not as low as that reported by Amdel or by WAIT AID [257].
I have already referred to the erroneous significance which the trial judge attached to the 'peak loads' experienced during short periods of greater exposure.

The James Hardie Asbestos Cement Cutting Tool Study

A study undertaken for Amaca in 1980 of the concentrations of asbestos fibre dust generated from a variety of manual, machine and other processes conducted on Amaca products was tendered in evidence. The conclusions drawn by the trial judge from that study were:
Again, there must be some doubt about the comparability of these tests and findings with other reported test results relied upon by the first and second defendants and the conditions experienced by Mr Cotton when working for the first defendant in Adelaide. Generally speaking, however, these results are more consistent with the American A/C Pipe Producers' Reports which have been described and show results higher (approximately by a factor of 10) than those reported upon by WAIT AID and by Amdel. Again, however, the general tenor of the report is that airborne concentrations of asbestos fibres from the processing of AC pipe in the open by the methods likely to have been followed when Mr Cotton was employed in Adelaide are relatively low [259].

The Ontario Royal Commission Report

The report of the Royal Commission on Health and Safety conducted in Ontario in 1984 was also tendered in evidence. The conclusions drawn by the trial judge from that report were:
Another similar study is the report of the Royal Commission on Health and Safety Arising from the Use of Asbestos in Ontario, delivered in 1984 (Exhibit 177). This shows (in Table 10.4) exposure levels in construction work for the various processes using asbestos cement sheet and pipes, including United Kingdom data and other reported data for the compression shearing of pipe. This data shows levels slightly higher than those reported on in the other studies discussed so far, but still comparatively low [260].

Summary of the reports and studies

Of the six reports tendered in evidence and referred to by the trial judge, all but the Kumagai Study were found by the trial judge to support the conclusion that Mr Cotton's likely exposure to asbestos fibre while employed by EWSD was relatively low. Two of those reports, being the WAIT AID Study and the Amdel Report, suggested levels of exposure significantly lower than the other reports. Those two reports were entirely discounted by the trial judge for reasons which depended in part upon his erroneous conclusion as to the composition of the pipes upon which Mr Cotton worked by employed by EWSD. Notwithstanding the conclusion of the trial judge to the effect that:
[T]he Japanese study reported on a level of exposure to asbestos contamination appreciably greater than that probably experienced by Mr Cotton [261].
The trial judge appears to have placed greater reliance upon that study than the WAIT AID Study or the Amdel Report.
It is necessary now to consider the effect which the errors made by the trial judge, in the assessment of the relevance of the reports to which I have referred, had upon his evaluation of the evidence given in respect of the quantification of Mr Cotton's exposure to respirable asbestos fibre.

Mrs Janet Sowden

Mrs Sowden is an occupational hygienist who has specialised in the issues relating to asbestos disease and industrial exposure to asbestos for many years. As the trial judge found:
She is well known and respected in the scientific disciplines associated with the study and effects of occupational asbestos exposure [285].
The trial judge made the following observations in respect of her evidence:
Mrs Sowden has never taken any measurements of asbestos exposure during the laying of AC pipes but has other experience in asbestos cement products which she says can be extrapolated to that situation. In her other works in this area most of her measurements showed exposures to be less than 1 fb/ml, although occasional very high short-term exposures of up to 60 fb/mls occurred in factory situations. She observed that measurements taken during brief periods of high exposure - short-term measurements - may be valuable for control purposes but are not useful for assessing exposures to substances such as asbestos where the pathological effect is the result of accumulation in the body over a long period. On those assumptions Mrs Sowden's observations are no doubt apt, but it remains the fact that there is controversy about the effect of asbestos exposure and that, Professor de Klerk and others do not accept that asbestos related lung cancer is due to a long accumulation of asbestos exposure but, instead, maintain that short-term exposures, without accumulation, can be significant [287].
The last sentence of this paragraph is one of those instances upon which the trial judge has erroneously asserted that short-term peak exposures can be more toxic than long-term accumulation of asbestos fibre in the body. On the hearing of the appeal, the respondent properly conceded that assertion to be erroneous. It is apparent from the paragraph of the reasons set out above, that the erroneous conclusion drawn by the trial judge in this respect has affected his evaluation of the evidence given by Mrs Sowden.
Four reports prepared by Mrs Sowden were tendered in evidence. As the trial judge found [288] in her first estimate she estimated Mr Cotton's cumulative exposure to respirable asbestos fibre while employed by EWSD as 1.6 fb/ml years. In her second and subsequent reports, she relied upon the WAIT AID Study and the Amdel Report to reduce her estimate to a total cumulative exposure of less than 0.2 fb/ml years. The trial judge rejected those estimates because of the view which he formed in relation to the irrelevance of the WAIT AID Study and the Amdel Report. The trial judge diminished the weight given to Mrs Sowden's evidence in which she was critical of the evidence given by others for the same reason - that is, what he considered to be her inappropriate reliance upon the WAIT AID Study and the Amdel Report [297].
The weight given by the trial judge to the evidence given by Mrs Sowden was adversely affected by the errors of fact which he made in respect of the relevance of the WAIT AID Study and the Amdel Report, and the significance of short‑term peak exposures. While the distinctions between the work undertaken by Mr Cotton when employed by EWSD, and the work the subject of the WAIT AID Study and the Amdel Report suggested a cautious approach should be taken to Mrs Sowden's estimates based upon those studies, those considerations do not apply to her initial estimate of cumulative exposure of 1.6 fb/ml, which was uninfluenced by the WAIT AID Study and the Amdel Report.

Mr Geoffrey Pickford

Mr Geoffrey Pickford is also an occupational hygienist. Like Mrs Sowden, he has made a long study of testing for airborne asbestos [300]. The conclusions drawn by the trial judge in respect of Mr Pickford's evidence were:
Essentially, Mr Pickford's opinion is that the best estimate of Mr Cotton's exposure to asbestos during the asbestos cement pipe laying work in Adelaide is a cumulative dose of 0.09 fb/ml years. As this is so much less than the 25 fb/ml years (Helsinki criteria), Mr Pickford is of the opinion that Mr Cotton's dose is insignificantly small and indicates that his airborne asbestos exposure as a pipe layer would not contribute to his lung cancer. Generally speaking, Mr Pickford's opinion is prone to the same criticisms which I consider deprive the second, third and fourth reports of Mrs Sowden of persuasive effect (Exhibits 152(2) to (4)). These are that Mr Pickford:
•treats the Helsinki criteria of 25 fb/ml years exposure to asbestos as a minimum exposure for attribution of asbestos-induced lung cancer, either alone or in combination with smoking;
•accepts the Amdel Report as establishing that the use of the Wheeler cutter on asbestos pipes results in exposure of less than 0.1 fb/ml on an open field work site;
•also accepts the WAIT AID Report as establishing that working with asbestos cement pipes on an open field site using the Wheeler cutter results in an exposure of less than 0.1 fb/ml of air;
•interprets the James Hardie Asbestos Cement Cutting Tool Cutting Study by Mr P A King (Exhibit 176, [258] - [259] above) which revealed an average personal airborne asbestos fibre concentration of 1.1 fb/ml when working with a manual lathe as unrepresentative of typical field use in the open air; and
•rejected the Ontario Royal Commission Report of 1984 (Exhibit 177, [258] above) findings of airborne asbestos fibre concentration based on UK data and USA data as being unrepresentative because they involved continuous asbestos cutting operations without interruption.
Mr Pickford did not discuss the effect of peak short-term loads.
Mr Pickford then went on to estimate Mr Cotton's possible airborne asbestos dose by reference to the exposure of the standards reported in the Amdel Report (Exhibits 153(6); 174 and 286) and, by a process of reasoning, set out in Exhibit 220 which involved diminutions in those figures for various reasons, came up with a final total laying dose of 0.9 fb/ml years. This compares with 1.6 fb/ml years in Mrs Sowden's first report (Exhibit 152(1)) and 0.2 fb/ml years in Mrs Sowden's subsequent reports.
While I do accept that Mr Cotton's aggregate exposure to asbestos while working with the second defendant's products in Adelaide for the first defendant was a lot less than 25 fb/ml years, I consider that Mr Pickford's conclusions are gross underestimates and are based on the WAIT AID and Amdel reports which I have already concluded are not reliable representations of that level of exposure - indeed, varying from other international studies of comparable activities by more than one order of magnitude. I am therefore not able to accept Mr Pickford's quantitative opinion about the aggregate exposure to asbestos experienced by Mr Cotton. I note that he did not attempt to make any estimate of Mr Cotton's exposure to asbestos while working with Millennium Inorganic Chemicals [301] ‑ [303].

When he came to express his ultimate conclusion, the trial judge said [754]:
Realising that the effort can, at best, be approximate and, at worst, arbitrary, I consider that a reduction of the plaintiff's damages because of Mr Cotton's contributory negligence should be made by a factor of 10 per cent and that, because of the progressive and cumulative effect of the progress of the disease, involving interaction between the effects of smoking and asbestos, this should apply to the damages to be awarded both in the claims against [EWSD] and [Amaca] for the asbestos exposure in South Australia, and in the claims against [Millennium] for the asbestos exposure at Bunbury.
This last reference obviously relates only to the non‑contractual claims against EWSD and Millennium.

The appellants' contentions

Counsel for the appellants contends that the reduction of 10% is far too low especially when regard is had to the trial judge's finding that the risk of lung cancer created by smoking was very much greater than the risk from asbestos. He also contends that, although the trial judge acknowledged that the test was objective, he applied a subjective test. He gives as an example the fact that, although warnings were on cigarette packets before Mr Cotton commenced smoking in 1973, the trial judge found that contributory negligence should only apply from 1992, when Mr Cotton was told to stop smoking by his general practitioner. Finally, the appellants contend that the trial judge did not deal with a submission, made at the trial, that Mr Cotton's smoking habit constituted an aggravation of his loss eliminating or limiting his entitlement to damages: Commonwealth of Australia v Ryan [2002] NSWCA 372 [82]‑ [83].

The Ryan point

We will deal first with the Ryan point. In that case Hodgson JA said, obiter, in the context of a claim for damages by an ex‑seaman whose situation had been affected by other choices than those forced upon him by the appellant's negligence, that ([82] ‑ [83]):
A large part of the damages in this case appears to result from freely-made choices of the respondent, such as choices to over-indulge in alcohol and tobacco and the choice to leave the Navy. In so far as the jury awarded damages for the results of these choices, they may be taken to have found, as was open to them, that, but for the appellant's negligence, different choices would have been made. However, I am not certain that this is enough to make a tortfeasor liable for the consequences of freely-made choices. The law is slow to recognise a duty to prevent self-inflicted loss: see Reynolds v Katoomba RSL All Services Club Ltd (2001) 53 NSWLR 43, per Spigelman CJ at [20] ‑ [27] and cases there cited. This approach may also be relevant to the assessment of damages.
Unless a psychological or psychiatric condition, or perhaps an addiction, is such as to deprive a plaintiff in a substantial way of the ability to make his or her own choices, it may be that, in order to recover damages for the consequences of choices, a plaintiff would need to prove that it was objectively reasonable in his or her own interests to make those choices, in the light of what he or she knew at the time. This may be necessary to prove causation (as discussed in The Guildford [1956] P364), and not a matter of mitigation of damages, in respect of which the onus of proof would be on the defendant (Wenkart v Pitman (1998) 46 NSWLR 502). If the plaintiff does not prove this, then the consequent losses may perhaps be considered the plaintiff's own responsibility, and not something for which the defendant should pay damages.
These passages are not apposite in the present case. The respondent chose to smoke. He did not choose to work with asbestos knowing of the multiplicative effect, so far as lung cancer is concerned, of asbestos and cigarette smoking. The appellants, on the other hand, did know of this multiplicative effect, but failed to take reasonable precautions or give any warning. In such circumstances the loss could not be considered to be exclusively the respondent's responsibility.

Objective or subjective

There is no dispute that the test for contributory negligence is objective. In Joslyn v Berryman [2003] HCA 34; (2003) 214 CLR 552 [32], McHugh J said (quoting Lord Macmillan in Glasgow Corporation v Muir [1943] AC 448, 457) that contributory negligence, like negligence, 'eliminates the personal equation and is independent of the idiosyncrasies of the particular person whose conduct is in question'. That does not mean that all subjective factors must be ignored. For example, in considering whether a child is guilty of contributory negligence, the standard of care is tailored to the age of the child: McHale v Watson (1966) 115 CLR 199 (and see, as regards an aged plaintiff, Daly v Liverpool Corporation [1939] 2 All ER 142, 143 and, generally in this respect, Joslyn [32] (McHugh J)). Also, the question is what would have constituted the exercise of reasonable care by the plaintiff in the circumstances in which he found himself: Chandley v Roberts [2005] VSCA 273 [24] (Maxwell P, Nettle JA & Habersberger AJA concurring); Monie v Commonwealth of Australia [2007] NSWCA 230 [101] (Campbell JA, Mason P & Beazley JA concurring).
As will be apparent, the trial judge referred to a number of subjective features relating to Mr Cotton. For example, he mentioned that Mr Cotton was addicted to smoking to such a degree that, even after he was diagnosed with lung cancer, he continued to smoke. On the other hand, in one of the passages that we have quoted from his judgment [739], the trial judge accepted that the issue was required to be examined on an objective basis 'without regard to any actual addiction or dependence upon nicotine, however real that may be in fact'.
It is unnecessary to give this issue (and other references by the trial judge to what were said to have been subjective matters) any further consideration, given the conclusion at which we have arrived (below) that there was, in any event, an error in the assessment made by the trial judge.

Error in making the assessment

A plaintiff will be guilty of contributory negligence when the plaintiff exposes himself or herself to a risk of injury which might reasonably have been foreseen and avoided and suffers an injury within the class of risk to which the plaintiff was exposed: Joslyn [16] (McHugh J). Once contributory negligence is proved, a just and equitable apportionment must be made.
The relevant principles are addressed in Podrebersek v Australian Iron and Steel Pty Ltd (1985) 59 ALJR 492, 493 ‑ 494. The court (Gibbs CJ, Mason, Wilson, Brennan & Deane JJ) said that the making of an apportionment involves a comparison 'both of culpability, ie of the degree of departure from the standard of care of the reasonable man … and of the relative importance of the acts of the parties in causing the damage … '. The court also said that it was 'the whole conduct of each negligent party in relation to the circumstances' of the damage that 'must be subjected to comparative examination' (see also Wynbergen v Hoyts Corporation Pty Ltd [1997] HCA 52; 72 ALJR 65, 68 (Hayne J, with whom Gaudron, McHugh, Gummow & Kirby JJ agreed)). It is, of course, important to bear in mind that a finding on a question of apportionment is one upon a 'question not of principle or of positive findings of fact or law, but of proportion, of balance and relative emphasis, and of weighing different considerations … [involving] an individual choice or discretion, as to which there may well be differences of opinion by different minds': Owners of Steamship or Vessel 'British Fame' v Owners of Steamship or Vessel 'Macgregor' (The 'British Fame') [1943] AC 197, 201, quoted in Podrebersek (532). In Podrebersek (532), the court said that such a finding, if made by a judge, is not lightly reviewed.
As will be apparent, in the present case the trial judge mentioned that there was general evidence that Mr Cotton's risk of developing lung cancer due to tobacco would have declined over time, had he stopped smoking. The evidence of Professor Musk, Dr Kendall and Professor Christie was that cessation of smoking significantly decreased the risk of contracting lung cancer and that, after 20 to 25 years from cessation, the risk is approximately that of a person who had never smoked.
Mr Cotton must have known of the risks of smoking when he took up that habit. The evidence established that those risks were then well‑known and that there was increasing publicity in respect of them over the years. Professor Chapman said in his report dated 7 September 2005 that, since the 1960s, newspapers, radio and television reports about smoking have overwhelmingly described it as a health hazard and that it would certainly have been almost impossible for any ordinary citizen to avoid being exposed to such information. Accepting that he also said that this must be balanced against what he described as the efforts of the tobacco industry to cast doubt on the veracity of that information and its vast expenditure on advertisements featuring energetic and healthy people smoking, it seems to us that anyone exposed to the media reports must have known that there was widespread concern about the potentially serious consequences of smoking.
In our opinion it inevitably follows that Mr Cotton was substantially negligent to have taken up smoking and to have continued that habit over the years. We can, with due respect, see no basis for concluding that reasonable care for his own safety required him to give up smoking only in 1992. Enough was known at the time at which Mr Cotton first took up smoking to demonstrate that this revealed a lack of reasonable care for his own safety and, as the trial judge found, the level of awareness continued to increase over the ensuing period. In our respectful opinion, that error was sufficient to vitiate the trial judge's exercise of discretion.
That brings us to the question of what are the relative degrees of negligence of Amaca and Mr Cotton. We have earlier referred to evidence, particularly that of Professor Leigh, which established that, while exposure to either asbestos fibres or smoking is capable of causing lung cancer, it is more probable than not that the cancer will be the singular result of the two factors operating together and it is not possible to separate their effects in the individual case (see also the evidence of Professor Musk, ts 392). It is consequently very difficult, in a case involving cumulative causes of this kind, to make any assessment of the degree of risk posed by each of the causes when both are operative. As we have pointed out, the statistical analyses performed by the epidemiologists wrongly assume that tobacco smoke and asbestos are independent causes of lung cancer. We have also pointed out that the RR calculated by them assumes a linear constant relationship between dose and risk and does not accommodate or reflect the probabilities of acceleration of the contraction of a disease or the effect of intermittent high short‑term peak doses of asbestos. What seems to us to be more important than this kind of analysis is that Amaca knew that a significant risk of serious illness from asbestos exposure alone was brought about by work of the kind undertaken by Mr Cotton and, in particular, that exposure to small amounts of asbestos was capable of causing lung cancer. That risk was significant, even though it was very much smaller than the risk of contracting cancer from smoking alone, as appears from the evidence of the epidemiologists and others (for example, Professor Musk put the RR from smoking at 20 and that from asbestos exposure at EWSD as low as 1.03 ‑ 1.08). Most significant of all, for present purposes, is that Amaca knew that exposure to asbestos fibres was considerably more dangerous to a person who was a regular, long‑term smoker than it was to a non‑smoker.
We have already referred to the documents in Amaca's possession that reveal its knowledge, at the material time, of the risks posed by asbestos to a smoker, including the reports prepared by Dr McCullagh. The validity of the concerns expressed in this material was borne out by evidence at the trial, including that of Professor Wan who, in his report dated 12 April 2001 (exhibit 58), said that:
If the relative risk of developing cancer for members of the general population is expressed as 1, then that of smokers is up to 10 times as great. Exposure to asbestos alone over many years in the absence of smoking might marginally increase the relative risk, but where asbestos exposure is combined with cigarette smoking, the risk could be extraordinarily changed so that the relative risk of the combined exposure may approach 100 times that in the general population. The exact relationship is uncertain but is certainly far greater than merely an additive risk.
Amaca's failure to warn of the dangers to a smoker working with its asbestos cement products consequently showed a serious lack of reasonable care, given its knowledge of the magnitude and severity of the risk. In all of the circumstances, it seems to us that the appropriate apportionment, given the multiplicative effect of the two causes and what seems to us to have been a serious degree of negligence on both sides, is one of 50%. We would consequently allow the appeal in this respect, set aside the apportionment arrived at by the trial judge and substitute, for the figure of 10% arrived at by him, one of 50%.

Conclusion

We would dismiss grounds 1, 2, 3 and 5 of the grounds of appeal. We would uphold ground 4 and substitute for the reduction of 10% arrived at by the trial judge in respect of Mr Cotton's contributory negligence, a reduction of 50%. We would leave it to the parties to prepare a minute accordingly. We will hear further from the parties on the issue of costs.

JURISDICTION : SUPREME COURT OF WESTERN AUSTRALIA

TITLE OF COURT : THE COURT OF APPEAL (WA)

CITATION: THE STATE OF SOUTH AUSTRALIA -v- ELLIS [2008] WASCA 200 (S)

CORAM: MARTIN CJ
STEYTLER P
McLURE JA

HEARD: 12 - 14 FEBRUARY 2008
ON THE PAPERS 14 MAY 2008

DELIVERED : 26 SEPTEMBER 2008

SUPPLEMENTARY
DECISION :29 JANUARY 2009

FILE NO/S: CACV 11 of 2007
CACV 12 of 2007
CACV 13 of 2007

BETWEEN: THE STATE OF SOUTH AUSTRALIA
First Appellant
AMACA PTY LTD (ACN 000 035 512)
Second Appellant
MILLENNIUM INORGANIC CHEMICALS LTD (ACN 008 683 627)
Third Appellant
AND
TERESA ELLIS As Executor of the Estate of PAUL STEVEN COTTON (Dec)
Respondent

ON APPEAL FROM:
Jurisdiction              :  SUPREME COURT OF WESTERN AUSTRALIA
Coram  :EM HEENAN J
Citation  :ELLIS, Executor of the Estate of PAUL STEVEN COTTON (DEC) -v- THE STATE OF SOUTH AUSTRALIA & ORS [2006] WASC 270
File No  :CIV 2314 of 2000

Catchwords:

Costs - Rules of the Supreme Court, O 24A - Calderbank offer - Effect of contributory negligence on costs - Appellants to be taxed as one set - Turns on own facts

Legislation:

Rules of the Supreme Court 1971 (WA), O 24A

Result:

Orders made as to costs

Category: B

Representation:

Counsel:

First Appellant              :     Mr G M Watson SC & Ms C J Thatcher
Second Appellant          :     Mr G M Watson SC & Ms J M Kubacz
Third Appellant            :     Mr G M Watson SC & Mr S J Rushton
Respondent:     Mr B W Walker QC & Mr J R C Gordon

Solicitors:

First Appellant              :     State Solicitor for Western Australia
Second Appellant          :     Minter Ellison
Third Appellant            :     Lavan Legal
Respondent:     Slater & Gordon

Case(s) referred to in judgment(s):

The State of South Austalia v Ellis [2008] WASCA 200

JUDGMENT OF THE COURT: On 26 September 2008, the court's reasons for decision in the substantive appeal were published (The State of South Austalia v Ellis [2008] WASCA 200). In very general terms, the court, by a majority, concluded that the appeals of the first and third appellants should be dismissed, but that the appeal of the second appellant in respect of the apportionment of damages following the finding of contributory negligence should be allowed, and the reduction in damages as a result of that finding be increased from 10% to 50%.
Orders were made dismissing the appeals of the first and third appellants. Directions were made for the filing and service of minutes and submissions dealing with:
(a)the costs of the appeal; and
(b)any variation to the orders made in respect of the costs of the trial in the appeal by the second appellant.
No direction was made with respect to the filing and service of submissions as to the costs of the trial in relation to the appeals by the first and third appellants. That was because there was no disturbance of the orders made at trial in respect of those appellants. Directions were made in respect of the possible variation of the costs orders relating to the trial in the case of the appeal by the second appellant because the judgment entered against that appellant was altered as a result of the partial success of its appeal. The clear intent of that direction was to make provision for any appropriate variations to the costs orders made at trial as a result of the partial success of the second appellant's appeal.
Various issues have been raised by the parties in the submissions filed pursuant to those directions. We will deal with each of those issues in turn.

The costs of the trial

The respondent has filed submissions and an affidavit in support of an application that the orders made in respect of the costs of the trial be varied by providing that the appellants pay her costs of the trial on a party/party basis until 21 July 2005 (in the case of the first and third appellants) and 26 July 2005 (in the case of the second appellant), and thereafter on an indemnity basis. The basis of this application is entirely unrelated to the disposition of the appeal, and depends upon an offer made pursuant to O 24A of the Rules of the Supreme Court 1971 (WA) in the case of the first and third appellants, and a Calderbank offer in the case of the second appellant. In the case of the first and third appellants, the orders sought go beyond the directions made at the time of publication of reasons on 26 September 2008. In the case of the second appellant, the orders sought go beyond the intent of the directions made when reasons were published, as the orders sought are unrelated to the partial success of the second appellant's appeal.
An application for orders of this kind could and should have been made to the trial judge. It is not appropriate for this court to now deal with those applications. If the respondent wishes to agitate these matters further, the appropriate course is to bring an application before the trial judge.

The orders in the second appellant's appeal

The respondent has provided a minute in which a variety of orders are sought in respect of the second appellant's appeal, covering such things as the particular grounds which ought to be allowed, the payment of interest and so on. Many of the matters covered in the minute are unnecessary (such as the provisions relating to interest, which are covered by the Rules of the Supreme Court), and do not accord with the usual practice of the court. The appropriate orders made in the disposition of the second appellant's appeal are:
1.Appeal allowed in part.
2.The judgment against the second defendant be set aside and, in lieu thereof, judgment be entered against the second defendant:
(a)on the estate claim, in the amount of $213,468.42; and
(b)in the dependants' action, in the amount of $37,660.50.

The costs of the second appellant's appeal

The second appellant submits that the respondent should be ordered to pay 50% of its costs of its appeal, to reflect its partial success on appeal. There may be a superficial mathematical harmony in that proposition, because the result of the appeal was, in general terms, to reduce the amount of the judgment entered against the second appellant from 90% of the amount of the judgment entered against the first and third appellants, to 50% of that amount. However, the submission does not reflect any substantive evaluation of the significance of the second appellant's partial success on appeal for at least two reasons.

The first reason is that the submissions and argument in respect of apportionment as a consequence of the finding of contributory negligence occupied only a small portion of the argument on appeal. It was correctly accepted by all parties, in the course of argument, that apportionment is largely a matter of impression, and in this appeal the relevant impression was gained almost entirely from matters that were canvassed during the argument on the many issues upon which the second appellant failed. Viewed from the perspective of the substantive issues ventilated in the course of argument on the appeal, the second appellant was largely unsuccessful. An apportionment of costs as between the second appellant and the respondent by reference to the work and effort involved in the issues upon which they respectively succeeded would result in the majority of the costs of the second appellant's appeal being awarded to the respondent.
The second reason why the superficial mathematical harmony of the second appellant's submission should not be accepted in this case is that the court has no way of knowing what the substantive effect of the alteration of the judgment entered against the second appellant has had upon the contributions to be made by the various appellants to the judgments awarded in favour of the respondent. Those judgments have been entered against all appellants, and there have been no proceedings for contribution between the appellants. Accordingly, it cannot necessarily be concluded that the amount which is actually to be paid by the second appellant has been reduced by the amount of the reduced judgment.
The respondent submits that it would be inappropriate to either award the second appellant any part of its costs of the appeal or reduce the costs payable by the second appellant to the respondent by reason of its partial success on appeal. That is because the respondent offered to compromise her claim against the second appellant on 26 July 2005, prior to the commencement of the trial, on the basis that her claim be dismissed and each party bear their own costs. The second appellant rejected that offer and proceeded to trial. However, that is a matter that would be relevant only to the costs of the trial. The trial having proceeded to a judgment which was, in our view, partially erroneous, the second appellant was justified in bringing an appeal from that judgment.
Taking all these matters into account, in our view, the proper order in relation to the second appellant's appeal is that it pay 80% of the respondent's costs.

The costs in the appeals of the first and third appellants

The first appellant submits that it should be ordered to pay no more than one‑third of the respondent's costs of the appeal. There is no basis for such an order. The appeal was presented collectively on behalf of all three appellants. The first appellant was not responsible for only one‑third of the appeal, nor for any discrete issues in the appeal. Accordingly, the respondent should have her costs of the appeals brought by the first and third appellants, and 80% of her costs of the appeal brought by the second appellant, to be taxed as one set.

Summary

The orders appropriately made for the disposition of the second appellant's appeal are:
1.Appeal allowed in part.
2.The judgment against the second defendant be set aside and, in lieu thereof, judgment be entered against the second defendant:
(a)on the estate claim, in the amount of $213,468.42; and
(b)in the dependants' action, in the amount of $37,660.50.
The order appropriately made in respect of the costs of the appeal is that the first and third appellants pay the respondent's costs of the appeal, and the second appellant pay 80% of the respondent's costs of the appeal to be taxed as one set. The effect of this order will be that all appellants will be jointly and severally liable for 80% of the respondent's costs of the appeal, and the first and third appellants jointly and severally liable for the remaining 20% of the respondent's costs. The orders made by the trial judge are otherwise undisturbed.