BHP Billiton Ltd v Hamilton

[2013] SASCFC 75

SUPREME COURT OF SOUTH AUSTRALIA

(Full Court: Civil)

BHP BILLITON LTD v HAMILTON & ANOR

[2013] SASCFC 75

Judgment of The Full Court

(The Honourable Chief Justice Kourakis, The Honourable Justice Blue and The Honourable Justice Stanley)

15 August 2013

TORTS - NEGLIGENCE - ESSENTIALS OF ACTION FOR NEGLIGENCE - DUTY OF CARE - REASONABLE FORESEEABILITY OF DAMAGE - PARTICULAR CASES - DANGEROUS THINGS OR SUBSTANCES

TORTS - NEGLIGENCE - DANGEROUS AND INJURIOUS THINGS, ETC - BREACH OF DUTY OF CARE

TORTS - NEGLIGENCE - ESSENTIALS OF ACTION FOR NEGLIGENCE - DAMAGE - CAUSATION - GENERALLY

STATUTES - ACTS OF PARLIAMENT - INTERPRETATION - GENERAL APPROACHES TO INTERPRETATION - GENERALLY

DAMAGES - MEASURE AND REMOTENESS OF DAMAGES IN ACTIONS FOR TORT - MEASURE OF DAMAGES - PERSONAL INJURIES - PREVAILING STANDARDS OF GENERAL DAMAGES

Mrs Hamilton (as executor and in her own right) sued BHP Billiton Ltd in the District Court for damages for negligence leading to Mr Hamilton’s contraction of mesothelioma and ultimately his death. The trial Judge upheld the claim and awarded damages, which included damages for pain and suffering and loss of amenities of life of $115,000.

BHP appeals against the judgment on liability contending that the trial Judge erred in concluding that:

1.       BHP breached its duty of care to Mr Hamilton; and

2.       BHP’s breach of duty (if established) caused or contributed to Mr Hamilton’s contraction of mesothelioma.

Mrs Hamilton cross-appeals on quantum contending that the trial Judge’s award of $115,000 for pain, suffering and loss of amenities of life was manifestly inadequate.

Held by the Court dismissing the appeal:

As to negligence:

1. On its proper construction, where the pre-conditions are satisfied so as to enliven the presumption, s 8(2) of the Dust Diseases Act 2005 (SA) creates a rebuttable presumption that the defendant knew at the relevant time that some (ie any) exposure to asbestos dust could result in the plaintiff contracting any or all of the pathological conditions included in the definition of “dust disease” in s 3 of the Act (at [16]-[26] per Blue J and [201]-[207] per Stanley J, Kourakis CJ agreeing).

2.       The pre-conditions having been satisfied by the evidence led at trial, that presumption was engaged (at [27] per Blue J and [227]-[234] per Stanley J, Kourakis CJ agreeing).

3.       The trial Judge correctly found that BHP had failed to rebut the presumption (at [31]-[48] per Blue J and [239]-[248] per Stanley J, Kourakis CJ agreeing).

4.       The trial Judge correctly found that BHP was negligent in not taking steps which were available to it to reduce the inhalation of asbestos dust by its workers at Whyalla (at [53]-[56] per Blue J and [258]-[276] per Stanley J, Kourakis CJ agreeing).

As to causation:

5. Section 8(1) of the Act translates a mere possibility that a plaintiff’s exposure to asbestos dust resulting from a defendant’s negligence might have caused or contributed to his or her dust disease into an actuality or finding that the exposure did cause or contribute to the dust disease (at [64]-[65] per Blue J and [208]-[211] and [218]-[224] per Stanley J, Kourakis CJ agreeing).

6.       The trial Judge’s findings as to the avoidability of the great majority of the exposure if BHP had not been negligent and acceptance of the evidence of Professor Henderson were open to him and appropriate on the evidence (at [68]-[76] per Blue J and [218]-[224] and [299]-[303] per Stanley J, Kourakis CJ agreeing).

7. In the circumstances, it was proved that the exposure resulting from BHP’s negligence might have caused or contributed to Mr Hamilton’s mesothelioma within the meaning of and so as to relevantly to engage the presumption under section 8(1) of the Act (at [76] per Blue J and [282] and [299]-[303] per Stanley J, Kourakis CJ agreeing).

8.       On the evidence, the trial Judge correctly found that BHP had failed to rebut the presumption (at [86]-[92] per Blue J and [304]-[311] per Stanley J, Kourakis CJ agreeing).

9.       The trial Judge correctly concluded that Mr Hamilton’s exposure to asbestos dust resulting from BHP’s negligence caused or contributed to his mesothelioma (at [77] and [79] per Blue J and [312] per Stanley J, Kourakis CJ agreeing).

Held by the Court allowing the cross-appeal:

1.       In considering whether an award in this State is manifestly inadequate or excessive, it is permissible to have appropriate regard to appropriate awards in comparable cases at first instance and on appeal in this jurisdiction and other jurisdictions (at [101]-[118] per Blue J and [317]-[318] per Stanley J, Kourakis CJ agreeing).

2. The general level of damages for pain, suffering and loss of amenities in terminal illness cases such as Ewins v BHP Billiton Ltd (2005) 91 SASR 303 should be increased (at [140] per Blue J and [328] per Stanley J, Kourakis CJ agreeing).

3.       The assessment of damages in Mr Hamilton’s case of $115,000 for pain, suffering and loss of amenities was manifestly inadequate (at [140] per Blue J and [328] per Stanley J, Kourakis CJ agreeing).

4.       Damages for pain, suffering and loss of amenities is re-assessed at $190,000 (at [147] per Blue J and [330] per Stanley J, Kourakis CJ agreeing).

Acts Interpretation Act 1915 (SA) s 22(1); Civil Law (Wrongs) Act 2002 (ACT) s 99; Civili Liability Act 1936 (SA) s 52; Civili Liability Act 2002 (NSW) ss 16. 17, 17A; Civil Liability Act 2002 (WA) ss 9, 10A; Civil Liability Act 2002 (Tas) s 27, 28; Civil Liability Act 2003 (Qld) ss 61, 62; Compensation (Commonwealth Government Employees) Act 1971 (Cth) s 30; Dust Disease Act 2005 (SA) ss 3, 4, 8, 8(1), 8(2), 9(2); Dust Diseases Regulations 2006 (SA) Sch 1; Dust Diseases Tribunal Act 1989 (NSW) s 32; Jurisdiction of Courts (Cross-Vesting) Acts ss 4, 5; Motor Vehicle (Third Pary Insurance) Act 1943 (WA) s 3C; Personal Injuries (Liabilities and Damages) Act 2003 (NT) ss 27, 28; Safety, Rehabilitation and Compensation Act 1988 (Cth) s 45; Supreme Court Civil Rules 1987 (SA) rr 18.02, 18.03; Supreme Court Rules 1947 (SA) O 11, r 1; Workers Rehabilitation and Compensation Act 1986 (SA) ss 31, 113; Wrongs Act 1958 (Vic) ss 28G, 26H, 28HA, referred to.
Amaca Pty Ltd v Booth [2011] HCA 53; (2011) 246 CLR 36; BHP Billiton Ltd v Parker [2012] SASCFC 73; (2012) 113 SASR 206; Bird v The Commonwealth (1988) 165 CLR 1, applied.
Amaca Pty Ltd v King [2011] VSCA 447; Bennett v Minister for Community Welfare (1992) 176 CLR 408; Bonnington Castings Ltd v Wardlaw [1956] AC 613; Carson v John Fairfax & Sons Ltd (1993) 178 CLR 44; Chakravarti v Advertiser Newspapers Ltd (1998) 72 SASR 361; Commission for Railways (NSW) v Agalianos (1955) 92 CLR 390; Coyne v Citizen Finance Limited (1991) 172 CLR 211; CSR Ltd v Young (1998) Aust Torts Reports 81-468; (1998) 16 NSWCCR 56; Czatyrko v Edith Cowen University [2005] HCA 14; (2005) 79 ALJR 839; Ellis v State of South Australia 2006] WASC 270; Ewins v BHP Billiton Ltd [2005] SASC 95; (2005) 91 SASR 303; Hamilton v BHP Billiton Limited [2012] SADC 25; Hannell v Amaca Pty Ltd [2006] WASC 310; Hirsch v Bennett [1969] SASR 493; K-Generation Pty Ltd v Liquor Licensing Court [2009] HCA 4; (2009) 237 CLR 501; Lowes v Amaca Pty Ltd [2011] WASC 287; McGilvray v Amaca Pty Ltd [2001] WASC 345; Misiani v Welshpool Engineering Pty Ltd [2003] WASC 263; Neill v NSW Fresh Food and Ice Pty Ltd (1963) 108 CLR 362; New South Wales v Fahy [2007] HCA 20; (2007) 232 CLR 486; O’Gorman v Sydney South West Area Health Service [2008] NSWSC 1127; Packer v Cameron (1989) 54 SASR 246; Parkinson v Lend Lease Securities and Investments Pty Ltd [2010] ACTSC 49; (2010) 4 ACTLR 213; Perez v The State of New South Wales [2013] NSWDDT 1; Planet Fisheries Pty Ltd v La Rosa (1968) 119 CLR 118; Project Blue Sky Inc v Australian Broadcasting Authority [1998] HCA 28; (1998) 194 CLR 355; Reynolds v Comcare [2006] SADC 136; Saeed v Minister for Immigration and Citizenship [2010] HCA 23; (2010) 241 CLR 252; Sienkiewicz v Greif (UK) Ltd [2011] 2 AC 229; Waugh v Kippen (1986) 160 CLR 156; WorkCover Corporation v Perre [1999] SASC 564; (1999) 76 SASR 95; Wyong Shire Council v Shirt (1980) 146 CLR 40, discussed.
Amaca Pty Ltd v Hannell [2007] WASCA 158; (2007) 34 WAR 109; Bank of New South Wales v Commonwealth (1948) 76 CLR 1; Bankstown Foundry Pty Ltd v Braistina (1986) 160 CLR 301; Betts v Whittingslowe (1945) 71 CLR 637; Bull v Attorney-General (NSW) (1913) 17 CLR 370; Burch v South Australia (1998) 71 SASR 12; Chanter v Blackwood (1904) 1 CLR 39; Easther v Amaca Pty Ltd [2001] WASC 328; Farah Constructions Pty Ltd v Say-Dee Pty Ltd [2007] HCA 22; (2007) 230 CLR 89; Fox v Percy [2002] HCA 22; (2003) 214 CLR 118; Graham Barclay Oysters Pty Ltd v Ryan [2002] HCA 54; (2002) 211 CLR 540; Hamilton v Nuroof (WA) Pty Ltd [2012] SADC 25; IW v City of Perth (1997) 191 CLR 1; John Pfeiffer Pty Ltd v Rogerson [2000] HCA 36; (2000) 203 CLR 503; Joyce v Pioneer Tourist Coaches Pty Ltd [1969] SASR 501; Lange v Australian Broadcasting Corporation (1997) 189 CLR 520; Mabo v Queensland (No 2) (1995) 175 CLR 1; March v E & MH Stramare Pty Ltd (1991) 171 CLR 506; Nemer v Holloway [2003] SASC 372; (2003) 87 SASR 147; Owen v South Australia (1996) 66 SASR 251; Police v Cadd (1997) 69 SASR 150; R v Place [2002] SASC 101; (2002) 81 SASR 395; Roads and Traffic Authority v Royal [2008] HCA 19; (2008) 82 ALJR 870; Roads and Traffic Authority of New South Wales v Dederer [2007] HCA 42; (2007) 234 CLR 330; South Australian Housing Trust v State Government Insurance Commission (1989) 51 SASR 1; Stateliner Pty Ltd v Legal & General Assurance Society Ltd (1981) 28 SASR 16; The State of South Australia v Ellis [2008] WASCA 200; (2008) 37 WAR 1; Sydney South West Area Health Service v Stamoulis [2009] NSWCA 153; Tesco Supermarkets Ltd v Nattrass [1972] AC 153; Vozza v Tooth & Co Ltd (1964) 112 CLR 316; Wakeline v London and South Western Railway Co (1886) 12 App Cas 41, considered.

WORDS AND PHRASES CONSIDERED/DEFINED

"Dust Disease"
"Asbestos Related Disease"

BHP BILLITON LTD v HAMILTON & ANOR
[2013] SASCFC 75

KOURAKIS CJ:        

1. I would dismiss the appeal for the reasons given by Blue and Stanley JJ.  I would allow the cross-appeal and join in the orders proposed by them for the reasons they give.

   BLUE J:

2. The respondent/plaintiff Mrs Hamilton (as executor of the estate of Mr Hamilton and in her own right) sued BHP Billiton in the District Court for damages for negligence leading to Mr Hamilton’s contraction of mesothelioma and ultimately his death.  The trial Judge upheld Mrs Hamilton’s claim and awarded damages of $232,704.96 (inclusive of interest), which included damages for pain and suffering and loss of amenities of life of $115,000. 

3. BHP appeals against the judgment on liability and Mrs Hamilton cross appeals on quantum.

4. The issues which arise on BHP’s appeal are whether the trial Judge erred[1] in concluding that:

   1.BHP breached its duty of care to Mr Hamilton;

   2.BHP’s breach of duty (if established) caused or contributed to Mr Hamilton’s contraction of mesothelioma.

   [1]    Adopting the approach articulated in Fox v Percy [2002] HCA 22; (2003) 214 CLR 118 at [21]-[31] per Gleeson CJ, Gummow and Kirby JJ.

5. The issues which arise on Mrs Hamilton’s cross appeal are:

   1.the extent to which the trial Judge was entitled, or this Court on appeal is entitled, to have regard to comparable awards in this or other jurisdictions;

   2.whether the trial Judge’s award of $115,000 for pain, suffering and loss of amenities of life was manifestly inadequate.

6. The relevant facts, evidence, reasoning of the trial Judge and arguments on appeal are set out in the reasons for judgment of Stanley J.

   Existence and content of duty of care

7. The existence of a duty of care was and is not in dispute.  The relationship of employer and employee is a clearly established category in which a duty of care arises.[2]  It is also clearly established that the duty of care owed by an employer to an employee is a duty to take reasonable care for the employee’s safety which encompasses providing a safe place and system of work and avoiding exposing the employee to unnecessary risks of injury.[3] 

   [2]    Czatyrko v Edith Cowen University [2005] HCA 14; (2005) 79 ALJR 839 at [12] per Gleeson CJ, McHugh, Hayne, Callinan and Heydon JJ.

   [3]    Bankstown Foundry Pty Ltd v Braistina (1986) 160 CLR 301 at 307-308 per Mason, Wilson and Dawson JJ; Czatyrko v Edith Cowen University  (2005) 79 ALJR 839 at [12]-[16] per Gleeson CJ, McHugh, Hayne, Callinan and Heydon JJ; BHP Billiton Ltd v Parker [2012] SASCFC 73; (2012) 113 SASR 206 at [12]-[13] per Doyle CJ and White J.

8. Parties (plaintiffs and/or defendants) sometimes seek to define the content of the duty of care in specific terms tailored to the particular circumstances of the breach in a manner in which the definition of the content of the duty answers (affirmatively or negatively) the issue of breach.  BHP’s submissions on appeal at times were expressed in terms of there being a dispute about the content of the duty of care owed by BHP to Mr Hamilton.  In reality, the dispute is not about the content of the duty of care (which is as expressed in the previous paragraph), but rather whether BHP was in breach of that duty of care.  Issues of breach should not be disguised as issues of content of duty.[4]

   [4]    See Graham Barclay Oysters Pty Ltd v Ryan (2002) 211 CLR 540 at [106] per McHugh J and [187] and [191]-[192] per Gummow and Hayne JJ; New South Wales v Fahy (2007) 232 CLR 486 at [53] per Gummow and Hayne JJ.

   Breach of duty of care

9. BHP contends that the trial Judge made a series of errors in reaching his conclusion that BHP breached a duty of care owed to Mr Hamilton.

10. The issues concerning breach of duty of care are whether the trial Judge erred:

    (a) in construing section 8(2) of the Dust Diseases Act 2005 (SA) (“the Act”) so as to presume that BHP knew that exposure to asbestos dust at any level could result in a dust disease;

    (b)  in finding that BHP had not rebutted the presumption;

    (c)  in finding in the alternative that Mrs Hamilton had proved that contraction of a dust disease by Mr Hamilton was reasonably foreseeable by BHP in accordance with common law principles;

    (d)  in finding that precautions and protections were reasonably available to BHP to minimise Mr Hamilton’s exposure to asbestos dust and risk of contracting a dust disease;

    (e)  in finding that a reasonable employer in BHP’s position would have undertaken and provided such precautions and protections.

    Statutory presumption of knowledge: construction of section 8(2)

11. At trial, the issue whether BHP had relevant presumed knowledge turned on the construction of section 8(2) of the Act. That subsection provides:

    A person who, at a particular time, carried on a prescribed industrial or commercial process that could have resulted in the exposure of another to asbestos dust will be presumed, in the absence of proof to the contrary, to have known at the relevant time that exposure to asbestos dust could result in a dust disease.

12. The trial Judge construed section 8(2) such that, when the presumption is engaged, the defendant is presumed to have actual (subjective) knowledge, not that a reasonable person in the defendant’s position would foresee the risk of a dust disease resulting (constructive knowledge).[5] On appeal, BHP accepts that construction.

    [5]    [2012] SADC 25 at [350] and [355]-[357].

13. The trial Judge construed section 8(2) such that the presumed knowledge is that exposure at any level to asbestos dust could result in a dust disease.[6] BHP contends that the trial Judge misconstrued the section and that the presumed knowledge (when the presumption is engaged) is that exposure at sufficient levels to asbestos dust could result in a dust disease without the subsection addressing what is a sufficient level for this purpose.  BHP’s senior counsel coined the convenient shorthand term “generalised knowledge” to denote this latter concept.

    [6] Ibid at [349].

14. In approaching the construction of section 8(2), four matters can be observed. The subsection is confined in its application to a defendant who carried on a prescribed industrial or commercial process at the relevant time: it does not apply to any defendant or any employer. The knowledge which is presumed is that exposure to asbestos dust could result in a dust disease, which refers to a possibility rather than a probability or certainty. Leaving aside the tense, the subsection uses the same phrase (could have resulted) to link the prescribed process to the exposure as it uses (could result) to link (in the mind of the defendant) the exposure to a dust disease.  To enliven the presumption, it is sufficient that some exposure to asbestos dust could have resulted from the prescribed process: there is no requisite amount of exposure specified to trigger the presumption.

15. The subsection operates against the background and in the context of the common law defining what constitutes breach of duty: the subsection addresses one element of breach of duty but does not otherwise modify the common law.

16. The literal meaning of the words “known … that exposure to asbestos dust could result in a dust disease” is that the presumed knowledge is that some exposure to asbestos dust (with no requisite quantity) could result in a dust disease.  The construction advanced by BHP requires additional words to be read into the section along the lines of “known … that exposure to asbestos dust at sufficient levels could result in a dust disease”.  There is no warrant for reading in such words. 

17. Both the structure and evident purpose of the subsection indicate that it is self-contained in creating the presumption.  On BHP’s construction, to give operative content to the presumption, it would always be necessary for the plaintiff to adduce extrinsic evidence of what was known by the defendant at the relevant time to be sufficient levels of exposure to asbestos dust such that a dust disease could result. 

18. While the subsection uses the definite article when referring to exposure to asbestos dust in defining the second precondition to enliven the presumption (“the exposure … to asbestos dust”), it does not use either the definite or indefinite article when referring to exposure as the subject matter of the presumed knowledge (“exposure to asbestos dust”).  The presumed knowledge is simply that exposure to asbestos dust could result in a dust disease, not a given level of exposure to asbestos dust.  The fact that the presumed knowledge is of the possibility, rather than probability or certainty, of a dust disease resulting from exposure supports a construction that the presumed knowledge does not refer to a sufficient level of exposure to asbestos dust.

19. This construction is supported by the evident purpose of the subsection.  The subsection was enacted against the background of the common law which defines the elements of causes of action, especially the cause of action of breach of duty of care.  Knowledge of risk (actual or constructive) is usually an essential element in establishing breach of a duty of care.[7]  If knowledge of the relevant risk is established, the enquiry proceeds to the steps which could and should have been taken by a reasonable person in the position of the defendant.[8]  The evident purpose of the subsection is to create a presumption of knowledge of the relevant risk merely upon proof that the defendant carried on a prescribed process and that the process could have resulted in the exposure of the plaintiff to asbestos dust.  The purpose is to aid the proof of a component of the plaintiff’s cause of action.

    [7]    Knowledge of risk (actual or constructive) can also be an important element going to the existence of a duty of care in other than established categories in which a duty of care arises.  However, in established categories of duty of care, such as employer and employee, the existence of a duty of care is usually uncontroversial.

    [8]    Wyong Shire Council v Shirt (1980) 146 CLR 40 at 47-48 per Mason J (Stephen J and Aickin J agreeing).

1. If a plaintiff were required to prove aliunde the level of exposure to asbestos dust which the defendant knew (or ought to have known) could result in a dust disease, the subsection would have little, if any, practical operation.

2. In BHP Billiton Ltd v Parker,[9] this Court considered section 9(2) of the Act which addresses exemplary damages. It was held that section 9(2) empowers, but does not mandate, an award of exemplary damages when the specified pre-requisites are satisfied (being pre-requisites which differ from those at common law).[10] Section 9(2) provides:

   The Court should make an award of exemplary damages in each case against a defendant if it is satisfied that the defendant—

   (a)     knew that the injured person was at risk of exposure to asbestos dust, or      carried on a prescribed industrial or commercial process that resulted in the               injured person's exposure to asbestos dust; and

   (b)     knew, at the time of the injured person's exposure to asbestos dust, that        exposure to asbestos dust could result in a dust disease.

   [9] (2012) 113 SASR 206.

   [10] Ibid at [228]-[232] per Doyle CJ and White J and [411]-[412] per Gray J.

3. In the present case, no issue arises under section 9(2). In BHP Billiton Ltd v Parker, in the course of construing the phrase “knew … that exposure to asbestos dust could result in a dust disease” appearing in section 9(2)(b), Doyle CJ and White J expressed the following obiter view concerning the meaning of the similar phrase appearing in section 8(2):

   It can be seen that s 8(2) also includes the expression “that exposure to asbestos dust could result in a dust disease”. It is reasonable to suppose that the Parliament intended the expression to have the same meaning in each provision. Thus, if the construction proposed by BHP is correct, s 8(2) would require a presumption, in the absence of proof to the contrary, that a defendant who carried on a prescribed process knew, at the relevant time, that the particular exposure of a plaintiff (as opposed to exposure more generally) could result in a dust disease. That does not appear to be the ordinary meaning of s 8(2). It is more natural to understand the second use of the expression “exposure to asbestos dust” in s 8(2) as referring to the same kind of exposure to which the expression when first used refers, ie, any exposure at all. Persons who carry on a process which could result in the exposure of another to asbestos dust (ie, any exposure) are to be presumed, in the absence of proof to the contrary, to know that exposure (ie, exposure generally) could result in a dust disease.[11]

   [11] Ibid at [224] per Doyle CJ and White J.

4. If the last sentence quoted in the previous paragraph were considered in isolation, the words “exposure generally” might be regarded as ambiguous, capable of meaning either “any exposure” or “exposure at sufficient levels”. However, the previous sentence unequivocally construes the second use of the expression “exposure to asbestos dust” in section 8(2) as referring to “any exposure at all”.  The obiter observation by Doyle CJ and White J therefore supports the construction adopted by the trial Judge.

5. In any event, while the decision in BHP Billiton Limited v Parker is binding as to the construction of section 9(2), the opinion expressed by Doyle CJ and White J as to the construction of section 8(2) was obiter.  There would be no disharmony between one construction of the relevant phrase in section 8(2) and a different construction of the same phrase in section 9(2). The context and purpose of section 9(2) are very different to those of section 8(2). Section 8(2) addresses an essential element in the cause of action (negligence, at least). Section 9(2) addresses an additional head of damages, exemplary damages, which requires additional elements to those comprising the cause of action. Section 8(2) addresses presumed knowledge (as the outcome of the operation of the section). Section 9(2) addresses actual knowledge (as a criterion for the award of exemplary damages).

6. Finally, in BHP Billiton Limited v Parker, Doyle CJ and White J applied section 8(2) directly in a manner consistent with the construction adopted by the trial Judge and inconsistent with the construction advanced by BHP identified at [13] above. They said:

   … by s 8(2) of the DDA, BHP is presumed to have known in 1971 and 1972 that exposure to asbestos dust could result in a dust disease. BHP carried on "a prescribed industrial or commercial process": see the Dust Diseases Variation Regulations 2009 (SA), Sch 1, Items 6(a), 7(a) and 8(a). That process could have resulted in the exposure of Mr Parker to asbestos dust. BHP is presumed to have known in 1971 and 1972 that Mr Parker's exposure to asbestos dust could result in dust disease.[12]

   [12] Ibid at [27] per Doyle CJ and White J.

7. In conclusion, on its proper construction, where the pre-conditions are satisfied so as to enliven the presumption, section 8(2) creates a rebuttable presumption that the defendant knew at the relevant time that some (ie any) exposure to asbestos dust could result in a dust disease. BHP’s construction of the subsection should be rejected.

8. The trial Judge found that the pre-conditions for the presumption had been satisfied.[13]  On appeal, BHP does not challenge those findings.  It follows that BHP was presumed to have known in 1964/65 that some (ie any) exposure of Mr Hamilton and his fellow workers to asbestos dust could result in, inter alia¸ mesothelioma.

   [13] [2012] SADC 25 at [349].

   Rebuttal of the presumption

9. BHP accepts on appeal that, if the presumption is engaged, the onus of proof is thrown upon a defendant.[14]

   [14]   Compare, for example, WorkCover Corporation v Perre [1999] SASC 564; (1999) 76 SASR 95 at [28] per Mullighan J (Doyle CJ and Wicks J agreeing), addressing ss 31(2) and 113(2) of the Workers Rehabilitation and Compensation Act 1986 (SA).

10. The trial Judge found that BHP did not discharge the onus of rebutting the statutory presumption of knowledge of the risk of exposure to asbestos dust.[15]  BHP contends that the trial Judge erred in this conclusion.

    [15]   [2012] SADC 25 at [174]-[176], [192], [237], [358].

11. In reaching his conclusion that BHP had not rebutted the presumption, the trial Judge observed that no evidence as to BHP’s actual knowledge in 1964/65 was lead.  BHP’s primary contention on appeal is that the trial Judge erred because he appears to have thought that in order to rebut the presumption BHP needed to lead evidence from the officer or officers whose subjective knowledge was relevant, whereas such knowledge could be proved circumstantially by way of documentary evidence.

12. BHP’s primary contention should be rejected.  It can be accepted that, like any other fact, a state of mind such as knowledge may be proved by either direct or circumstantial evidence.[16]  However, at trial there was not only an absence of direct evidence, there was also an absence of circumstantial evidence capable of giving rise to an inference that BHP knew or believed that exposure to asbestos dust was safe (whether below any given level or at all).

    [16]   Edgington v Fitzmaurice (1885) 29 Ch D 459 at 483 per Bowen LJ.

13. BHP did not adduce any evidence at all, either testimonial or documentary, bearing on the actual knowledge of its officers in 1964/65 of the risks of exposure to asbestos dust.  It did not adduce any oral evidence from BHP officers concerning their state of knowledge in 1964/65 or at any time.  It did not adduce any evidence of its occupational health, safety and welfare systems, policies, practices, personnel or otherwise in 1964/65.  It did not adduce any evidence of its business records in 1964/65 which might comprise circumstantial evidence of BHP’s officers’ knowledge.  It did not adduce any evidence of inquiries made by BHP in or before 1964/65 concerning risks of exposure to asbestos dust.  It did not adduce any evidence of its having taken or made any measurements or estimates in or before 1964/65 of the levels of asbestos dust to which its workers were exposed or of any knowledge or belief of its officers as to those levels.  It did not adduce any evidence demonstrating or explaining an inability to adduce any such evidence.[17]  In these circumstances, the trial Judge rightly concluded that BHP had not adduced any evidence, direct or circumstantial, as to its officer’s actual knowledge in 1964/65. 

    [17]   BHP complains on appeal that there was no evidence at trial that the relevant officers were alive or available, or even who they were.  However, BHP did not adduce any evidence of any steps taken to attempt to ascertain the availability of evidence of the knowledge of the relevant officers in 1964/65, whether by way of testimony or from contemporaneous business records.

14. BHP’s secondary contention on appeal is that the trial Judge ought to have inferred from three bodies of circumstantial evidence adduced by BHP that its officers believed that workers such as Mr Hamilton were exposed to less than five million particles of asbestos dust per cubic foot of air (“5 mppcf”) and that exposure to such levels could not result in a dust disease and accordingly that BHP did not know that relevant exposures could result in a disease.

15. Both limbs of BHP’s secondary contention should be rejected.  As to the first limb, BHP did not adduce any evidence that its officers believed in 1964/65 that workers such as Mr Hamilton were exposed to less than 5 mppcf.  There was no evidence that BHP in or before 1964/65 undertook any testing or made any estimates of the levels of exposure of its workers to asbestos dust or had any belief on that topic.  BHP sought to prove through Mr Rogers’ assessments in 2008 and 2010 the objective levels of asbestos dust to which workers were exposed.  Leaving aside the fact that Mr Rogers had insufficient information and was in no position to determine whether or not 5 mppcf exceeded and the fact that the trial Judge rejected his evidence and found that it was inconsistent with evidence of the witnesses called by Mrs Hamilton, the relevant question was BHP’s contemporaneous knowledge or belief, not what might be assessed at trial to have been the objective reality.

16. As to the second limb, BHP did not adduce any evidence that its officers believed that exposure at levels below 5 mppcf was safe and could not result in a dust disease.  On such evidence as was adduced by BHP at trial, it was sheer speculation as to what its officers knew or believed in 1964/65 as to asbestos levels which could or could not result in a dust disease.

    External documents in existence in 1964/65

17. The first body of evidence from which BHP contends the trial Judge should have inferred that BHP did not have the relevant knowledge was a Schedule of Recommended Maximum Concentrations of Atmospheric Contaminants for Occupational Exposures issued by the National Health and Medical Research Council in 1961 (“the NHMRC Schedule”).  That Schedule contained recommended maximum concentrations for an extensive series of atmospheric contaminants, including asbestos dust for which the recommended figure was 5 mppcf.

18. BHP tendered the NHMRC Schedule together with a bundle of internal NHMRC documents, all of which were sourced from the NHMRC (exhibit R71).  They were not tendered out of BHP’s business records.  No evidence was adduced that BHP had the NHMRC Schedule in its possession in 1964/65.

19. No evidence was adduced by BHP that its officers knew of the NHMRC Schedule, the recommendations generally or the figure for asbestos dust.  The mere existence of the Schedule, of itself, was incapable of giving rise to an inference of BHP’s knowledge. 

20. The second body of evidence from which BHP contends the trial Judge should have inferred that BHP did not have the knowledge was a bundle of 7 scientific publications regarding asbestos dating from 1933 to 1960 (part of exhibit R69) (“the R69 Publications”).  While BHP relies upon these documents on appeal for the suggested inference, BHP apparently tendered these documents at trial on the basis that it did not concede that they were available to BHP, let alone that BHP had been aware of them.[18] These documents were not tendered out of BHP’s business records.  It appears from the trial Judge’s reasons that BHP did not rely upon these documents as evidence of its knowledge, but rather on the different issue of the reasonable foreseeability of risk by a reasonable employer in BHP’s position under common law principles.[19]     

    [18] [2012] SADC 25 at [192].

    [19] Ibid at [174]-[223].

21. No evidence was adduced that BHP was aware of the R69 Publications in 1964/65.  The mere existence of these publications in Australia, Britain, South Africa or the United States was incapable of giving rise to an inference concerning BHP’s knowledge.

22. Even if BHP had proved that it was aware of the asbestos dust component of the NHMRC Schedule or of the R69 Publications, that evidential fact would have rested in a vacuum.  There was no evidence, direct or circumstantial, as to what else BHP knew, what other information or scientific publications were accessed by BHP, how BHP assessed any information to which it had access, or otherwise from which any inference could be drawn about the state of BHP’s knowledge.  Nor, as observed above, was there any evidence as to BHP’s knowledge or belief concerning the levels of asbestos dust to which Mr Hamilton and his fellow workers were exposed, including to whether the exposure exceeded 5 mppcf.

23. Finally, as demonstrated by Stanley J’s analysis of five of the seven R69 Publications, they do not convey to a reader that exposure to asbestos is safe, and could not result in an asbestos disease, at levels below 5 mppcf.[20]

    Subsequent BHP internal documents

    [20] The trial Judge made findings that a reader of the publications tendered in evidence at trial would not have believed that exposures below 5 mppcf were safe: Ibid at [193]-[216], [362]-[380] and [393]-[394].

24. The third body of evidence from which BHP contends the trial Judge should have inferred that BHP did not have the relevant knowledge was a bundle of 32 internal BHP Whyalla documents ranging in date from October 1968 to October 1979 (exhibit R68).  BHP’s contention is that this evidence demonstrated that BHP did not know that exposures to asbestos dust at levels below 5 mppcf were not safe in 1968/69 and it could be inferred in turn that BHP did not know this in 1964/65.[21]

    [21] [2012] SADC 25 at [174] and [175]-[191].

25. BHP did not call any witnesses or adduce any evidence which explained or put into context the internal documents comprising exhibit R68.  It did not adduce any evidence to show that the documents were complete, in the sense of including all documents created by BHP over the 10 year period from 1968 to 1979 relating to asbestos, or that they were representative of what had been created or existed. 

26. As a miscellaneous collection of documents, the documents contained in exhibit R68 are insufficient, without any evidence to explain them or give them context, from which to draw an inference about BHP’s knowledge over the period 1968 to 1979.  A fortiori, they are insufficient to draw any inference about BHP’s knowledge in 1964/65.

27. If the documents had established that BHP did not know in 1968/69 that exposure to asbestos dust below 5 mppcf could result in a dust disease, it does not follow that BHP’s knowledge was identical four years earlier in 1964/65.  No evidence was adduced by BHP that knowledge inevitably advances with the passage of time.  History demonstrates that knowledge is often lost or deteriorates over time. 

28. Considered individually, there are documents within exhibit R68 which are suggestive that BHP knew in 1968/69 that asbestos dust exposure to its workers at the Whyalla shipyards could result in a dust disease.  The first document in exhibit R68 is a memorandum between safety superintendents dated 18 October 1968 referring to various protective measures, including vacuum cleaning and use of protective equipment (dust goggles, respirators and overalls) which should be taken.

29. BHP relies particularly upon reports of a visit on 28 November 1968 by Dr Wilson, Mr Stafford and Mr Turner of the Department of Health to the Whyalla shipyards.  Dr Wilson and Mr Turner subsequently prepared reports.  Dr Wilson’s report was provided to BHP.  It is apparent that they witnessed only limited operations which produced very small quantities of asbestos dust.  Their descriptions of dust are in stark contrast to the descriptions of witnesses called at trial by Ms Hamilton of conditions generally applying in 1964/65.  BHP did not adduce any evidence that those conditions observed by Dr Wilson and Mr Turner were representative of conditions generally prevailing in 1968/69 nor of those prevailing in 1964/65.  Notwithstanding the excellent conditions observed by Dr Wilson, he considered that various steps should be taken to minimise risk from asbestos dust, including overalls, respirators, wetting down, vacuum cleaning and segregation of sawing, sanding and drilling of asbestos.

    A further matter

30. BHP’s contentions addressed at [30] to [48] above proceed on the assumption that it would have been sufficient for BHP to rebut the presumption of knowledge to demonstrate that BHP did not know that relevant exposures could result in a dust disease.  It may be that, in order to rebut the presumption, BHP was required to prove that it knew that the relevant exposures could not result in a dust disease.[22]  However, given the conclusions reached above, there is no need to consider that question on this appeal.

    Conclusion

    [22]   Compare WorkCover Corporation v Perre (1999) 76 SASR 95 at [28] per Mullighan J (Doyle CJ and Wicks J agreeing) addressing ss 31(2) and 113(2) of the Workers Rehabilitation and Compensation Act 1986 (SA).

31. The trial Judge correctly found that BHP did not discharge the onus of proof concerning its knowledge that asbestos dust could result in a dust disease. Given this conclusion, it is unnecessary to consider the trial Judge’s alternative finding and Mrs Hamilton’s alternative contention that, independently of the Act, she proved that contraction of a dust disease by Mr Hamilton was reasonably foreseeable by BHP in accordance with common law principles.

    Availability of precautions and protections

32. Mrs Hamilton bore the onus of proving that there were practicable precautions available to BHP to eliminate or minimise the risk of injury to Mr Hamilton.[23]  However, as was said in Neill v NSW Fresh Food and Ice Pty Ltd[24] by Taylor and Owen JJ:

    No doubt in many cases no more than common knowledge, or perhaps common sense, is necessary to enable one to perceive the existence of a real risk of injury and to permit one to say what reasonable and appropriate precautions might appropriately be taken to avoid it.[25]

    [23]   Neill v NSW Fresh Food and Ice Pty Ltd (1963) 108 CLR 362 at 364-365 per Dixon CJ (McTiernan J agreeing), 365 per Kitto J and 369 per Taylor and Owen JJ; Vozza v Tooth & Co Ltd (1964) 112 CLR 316 at 319 per Windeyer J (McTiernan, Kitto, Taylor and Owen JJ agreeing).

    [24] (1963) 108 CLR 362.

    [25] Ibid at 368 per Taylor and Owen JJ.

33. The trial Judge found that as at 1964/65 there were simple precautions and protections available which could have been adopted by BHP to minimise the inhalation of asbestos dust by Mr Hamilton and his fellow workers.  Those precautions and protections were:

    1.isolating the preparation, application, sawing and drilling of asbestos from other workers;

    2.wetting down and using vacuum cleaners to minimise airborne asbestos dust; and

    3.providing and requiring the use of respirators and protective clothing coupled with warning of the risks of inhalation of asbestos dust.[26]

    [26] [2012] SADC 25 at [398]-[399].

34. As found by the trial Judge, the publications tendered in evidence (including R69 tendered by BHP) proved that such measures were available.  BHP has not demonstrated that the trial Judge erred in so finding.  BHP contends that, even if available, it did not know of a relevant risk and hence the need to consider precautions and protections.  The issue of BHP’s knowledge has been addressed above.

    Reasonable response to risk

1. Once it is established that a defendant is (or ought to be) aware of a relevant risk and that measures are available to alleviate the risk, the next question is whether a reasonable person in the position of the defendant would take those measures in all of the circumstances.  Those circumstances include the seriousness of the consequences if the risk eventuates, the likelihood of the risk eventuating and the expense, practicality and inconvenience of taking alleviating action.[27]

   [27]   Wyong Shire Council v Shirt (1980) 146 CLR 40 at 47-48 per Mason J (Stephen J and Aickin J agreeing).

2. The trial Judge found (applying the section 8(2) presumption) that BHP knew that asbestos was hazardous and could lead to serious dust diseases such as mesothelioma, the precautions identified were simple and straightforward and the only approach by a reasonable employer would have been to reduce the inhalation of dust so far as reasonably possible.[28] 

   [28] [2012] SADC 25 at [395]-[399].

3. BHP has not demonstrated material error by the trial Judge.  On the contrary, his conclusions concerning the response of a reasonable employer in BHP’s position were inevitable once the findings of knowledge of risk and availability of precautionary measures had been made. 

   Conclusion on negligence

4. The trial Judge correctly found that BHP was negligent in not taking the various steps identified by him to reduce the inhalation of asbestos dust by its workers at Whyalla. 

   Causation

5. BHP contends that the trial Judge made a series of errors in reaching his conclusion that BHP’s negligence caused the contraction of mesothelioma by Mr Hamilton.

6. The issues concerning causation are whether the trial Judge erred:

   a)in finding that the precondition for the presumption under section 8(1) of the Act was established that Mr Hamilton’s relevant exposure to asbestos dust might have caused or contributed to his mesothelioma;

   b)in finding that BHP had not rebutted the presumption;

   c)in finding in the alternative that Mrs Hamilton had proved that BHP’s negligence had caused or contributed to Mr Hamilton’s contraction of mesothelioma in accordance with common law principles.

   Statutory presumption of causation

7. Section 8(1) is enacted against the background and in the context of the common law principles which define causation as an essential element of the relevant cause of action, especially the cause of action of breach of duty of care. To establish causation, it is sufficient that the breach of duty is a cause of the injury; it need not be the sole or principal cause.[29]  A particular application of that approach to causation is that it is sufficient, where there are multiple causes of a disease or injury, that the defendant’s conduct materially contributed to the contraction of the disease or occurrence of the injury.[30] 

   [29]   March v E & MH Stramare Pty Ltd (1991) 171 CLR 506 at 509 per Mason CJ (Toohey J and Gaudron J agreeing) and 521-524 per Deane J (Gaudron J agreeing).

   [30]   Wakeline v London and South Western Railway Co (1886) 12 App Cas 41 at 47 per Lord Watson; Amaca Pty Ltd v Booth [2011] HCA 53; (2011) 246 CLR 36 at [70] per Gummow, Hayne and Crennan JJ.

8. At common law, establishing merely that it is possible that the defendant’s conduct was a cause of (or materially contributed to) the disease or injury is insufficient: it must be proved in accordance with the civil onus that it is probable that the defendant’s conduct was a cause of (or materially contributed to) the plaintiff’s disease or illness.[31]  There is also a distinction between a mere prospective risk that the defendant’s conduct might cause injury to the plaintiff and the possibility or probability that the defendant’s conduct assessed in retrospect did in fact cause the injury suffered by the plaintiff.[32]  This is not to say that, as an evidentiary matter, proof of risk of injury coupled with other circumstances may not be sufficient to prove causation on the balance of probabilities.[33]

   [31]   Amaca Pty Ltd v Ellis [2010] HCA 5; (2010) 240 CLR 111 at [51] per French CJ, Gummow, Hayne, Heydon, Crennan, Kiefel and Bell JJ; Amaca Pty Ltd v Booth (2011) 246 CLR 36 at [69]-[71] per Gummow, Hayne and Crennan JJ.

   [32]   Roads and Traffic Authority v Royal [2008] HCA 19; (2008) 82 ALJR 870 at [144] per Kiefel J; Amaca Pty Ltd v Booth (2011) 246 CLR 36 at [41] per French CJ.

   [33]   Betts v Whittingslowe (1945) 71 CLR 637 at 649 per Dixon J; Amaca Pty Ltd v Booth (2011) 246 CLR 36 at [42]-[50] per French CJ.

9. Section 8(1) of the Act provides:

   If it is established in a dust disease action that a person (the injured person)—

   (a)     suffers or suffered from a dust disease; and

   (b)     was exposed to asbestos dust in circumstances in which the exposure might          have caused or contributed to the disease,

   it will be presumed, in the absence of proof to the contrary, that the exposure to asbestos dust caused or contributed to the injured person's dust disease.

10. Three matters can be observed about the structure and context of the subsection.  The subsection uses the definite article and the same phrase “the exposure” in both the formulation of the second pre-condition for the creation of the presumption and in the subject matter of the operative presumption itself.  To establish the second pre-condition for the presumption, it is necessary to establish that the plaintiff’s exposure might have caused or contributed to the dust disease suffered by the plaintiff, not just any dust disease.  The subsection operates against the background of the common law of causation which requires that ordinarily the plaintiff must prove on the balance of probabilities that the defendant’s conduct was a cause of or materially contributed to the injury.

11. The effect of the statutory presumption is to translate a mere possibility (that the exposure might have caused or contributed to the plaintiff’s dust disease) into an actuality or finding[34] (that the exposure did cause or contribute to the plaintiff’s dust disease).  The statutory presumption overcomes the type of problem faced by a plaintiff such as that faced in Amaca Pty Ltd v Ellis[35] in which the plaintiff can only prove the possibility, but not the probability, that the exposure resulting from the defendant’s negligence caused or contributed to the plaintiff’s dust disease.  The reference to “the exposure” when used in the second pre-condition in paragraph (b) and the operational presumption in the body of the subsection is to whatever exposure is established as having possibly caused or contributed to the disease. 

    [34]   Compare the analysis of legal certainty derived from an assessment of probabilities in Bank of New South Wales v Commonwealth (1948) 76 CLR 1 at 340 per Dixon J; Amaca Pty Ltd v Ellis (2010) 240 CLR 111 at [6] per French CJ, Gummow, Hayne, Heydon, Crennan, Kiefel and Bell JJ and Amaca Pty Ltd v Booth (2011) 246 CLR 36 at [72] per Gummow , Hayne and Crennan JJ.

    [35] (2010) 240 CLR 111.

12. Because the subsection is intended to assist in the proof of causation linking the exposure resulting from the defendant’s negligence to the disease, the anticipation of the subsection is that a plaintiff will establish that the exposure which resulted from the defendant’s negligence (for which senior counsel for BHP coined the shorthand term “the negligent exposure”) might have caused or contributed to the disease and that this in turn will enliven the presumption that the negligent exposure did cause or contribute to the disease. The concept that the exposure “might” have caused or contributed to the disease is the same concept of mere possibility which the common law regards as inadequate in itself to prove causation as identified at [61] above.

13. If on the evidence it is only established that the total exposure (as opposed to the negligent exposure) to asbestos dust might have caused or contributed to the disease, the presumption created by the subsection will not assist in establishing the vital causative link between negligence and the plaintiff’s contraction of the disease.  However, if on the evidence it is established that the exposure which resulted from the negligence might have caused or contributed to the disease, the statutory presumption will establish (in the absence of proof to the contrary) the essential causative link.

14. This approach to the application of section 8(1) was adopted by this Court in BHP Billiton Ltd v Parker.[36]  Doyle CJ and White J said:

    The judge's findings establish that Mr Parker suffers from a dust disease. The requirement of subpara (a) is established. It is beyond argument that Mr Parker was exposed to asbestos dust. The judge's findings establish that that exposure "might have caused or contributed to the disease". The disease from which Mr Parker suffers is one attributable to exposure to asbestos dust. The evidence establishes that Mr Parker was exposed to asbestos dust for a period of time that could not be put aside as trifling, and in circumstances such that one could not say that the risk of contracting a dust disease was negligible. To the contrary, the evidence was such that there was a risk of the exposure causing Mr Parker to contract a dust disease. Accordingly, the requirements of subpara (b) were established. In light of the judge's findings, there is no basis for a conclusion that BHP has proved, on the balance of probabilities, that exposure to asbestos dust did not cause or contribute to Mr Parker's disease. To the contrary, the evidence establishes that he was exposed to asbestos dust for a period of time and in circumstances at the workplace such that there was a risk of him contracting a dust disease, and measures that might have reduced that risk to a low or negligible level were not taken by BHP.

    It follows that by operation of s 8(1) of the DDA, it was right of the judge to conclude that BHP's breach of duty caused Mr Parker's dust disease.[37]

    and Gray J said:

    I consider that the terms of s 8(1) had application. On the findings of the judge, Mr Parker was exposed to asbestos in circumstances where that exposure might have caused Mr Parker to suffer from a dust disease. In these circumstances, the presumption arose that exposure was a cause of Mr Parker's dust disease. Given the judge's findings about Mr Parker's exposure at Vickers Armstrong and Mr Parker's concession that the Vickers Armstrong exposure was also a cause of his asbestos related conditions, it may be concluded that BHP's conduct was a contributing cause and not the cause.[38]

    [36] (2012) 113 SASR 206.

    [37] Ibid at [117]-[118] per Doyle CJ and White J.

    [38] Ibid at [348] per Gray J.

    Proof of pre-condition

15. BHP contends that the trial Judge erred in finding that Mrs Hamilton proved that Mr Hamilton’s relevant exposure to asbestos dust might have caused or contributed to his mesothelioma.

16. BHPs primary contention is that the trial Judge did not make any finding that the negligent exposure might have caused or contributed to Mr Hamilton’s mesothelioma.  It is true that the question framed and answered by the trial Judge was whether Mr Hamilton’s exposure at Whyalla might have caused or contributed to his mesothelioma.[39]

    [39] [2012] SADC 25 at [344].

17. BHP contends that Mrs Hamilton did not prove, and there was no basis for a finding, that the exposure to asbestos dust at Whyalla resulting from BHP’s negligence might have caused or contributed to Mr Hamilton’s mesothelioma.

18. The trial Judge found that, if BHP had not been negligent and had taken reasonable precautions which he found a reasonable employer would have taken:

    the levels of asbestos dust inhaled by the deceased would have been a small fraction of what indeed he inhaled.[40]

    [40] [2012] SADC 25 at [398].

19. The trial Judge accepted Professor Henderson’s evidence from which it is clear that exposure of Mr Hamilton to asbestos dust at levels comprising a substantial majority of his total exposure at Whyalla might have caused or contributed to his mesothelioma.  When coupled with the trial Judge’s finding referred to in the previous paragraph, this compelled a finding that Mr Hamilton’s exposure to asbestos dust resulting from BHP’s negligence might have caused or contributed to his mesothelioma.  BHP’s primary contention should be rejected.

20. BHP’s secondary contention is that the trial Judge’s finding that reasonable precautions would have decreased the asbestos dust inhaled by Mr Hamilton to a small fraction of what he inhaled was not the subject of, or supported by, any expert evidence.  BHP further criticises the trial Judge’s finding on the ground that the trial Judge did not quantify the reduction.  BHP’s secondary contention should be rejected.

21. As summarised at [52] above, the steps which the trial Judge found would have been taken by a reasonable employer fell into three categories: segregating dust creating activities from other workers, minimising atmospheric dust, and personal protection for the workers. Steps taken within any one of those three categories in isolation would inevitably have reduced the exposure by at least an order of magnitude and probably several orders of magnitude. Taking steps within all three categories would have largely eliminated inhalation by reducing it to a small fraction of the dust actually inhaled. In the circumstances, there was no need for a precise quantification of the reduction in terms of a specific percentage, nor was there any need for expert evidence to support findings open on the evidence as a matter of common sense.

22. The trial Judge did in any event have available evidence to support his findings.  The papers tendered by both BHP (exhibit R69) and Mrs Hamilton (exhibit A35) comprised evidence of the effectiveness of such measures in vastly reducing the inhalation of asbestos dust. 

23. Once it is accepted that reasonable measures by a reasonable employer would have reduced levels of asbestos dust inhaled by Mr Hamilton to a small fraction of what he inhaled at Whyalla, there is no relevant distinction between the trial Judge’s finding that all of the exposure at Whyalla might have caused or contributed to his disease (which BHP does not challenge) and a finding that Mr Hamilton’s exposure resulting from BHP’s negligence might have caused or contributed to his disease (which BHP does challenge).  This conclusion is reinforced by an understanding of the effect of Professor Henderson’s evidence concerning the aetiology of mesothelioma resulting from the inhalation of asbestos fibres.  That evidence is addressed in the following section.

24. In conclusion, BHP has not demonstrated material error in the trial Judge’s finding that the statutory presumption was engaged and that, in the absence of proof to the contrary, Mr Hamilton’s exposure to asbestos dust resulting from BHP’s negligence caused or contributed to his mesothelioma.  On the contrary, that finding was appropriate on the evidence adduced.

    Rebuttal of the presumption

25. The trial Judge concluded that there was an absence of proof to the contrary.[41]  BHP contends that the presumption was rebutted.  BHP’s contention is a simple one.  BHP refers to the uncontested fact that Mr Hamilton’s exposure to asbestos dust in Scotland was greater than his exposure at Whyalla.  While BHP contended before the trial Judge that the finding should be a ratio of 19:1, on appeal it is content not to challenge the trial Judge’s finding that the ratio was 6:1.[42]  BHP’s contention is encapsulated in the following submission from its outline of submissions:

    … the evidence of causation established that the relationship between the inhalation of asbestos and the development of mesothelioma in an individual is the result of random events which can be (and apparently can only be) expressed in terms of “risk” or mathematical probability.  On any view, the balance of mathematical probability was overwhelmingly in favour of the Scottish risk rather than the Whyalla risk.  In fact, the true comparison was between the negligent exposure at Whyalla and all other exposure, whether in Scotland or (non-negligently) at Whyalla (or elsewhere in Australia).  This only made the balance more preponderant.

    [41] [2010] SADC 25 at [344].

    [42] Ibid at [330].

26. BHP’s contention should be rejected for three reasons.  It has failed to demonstrate that the trial Judge erred in his finding, based on his acceptance and understanding of Professor Henderson’s evidence, that Mr Hamilton’s exposure to asbestos dust at Whyalla significantly contributed to his contraction of mesothelioma.  Given that it adduced no medical evidence of its own, it failed to discharge the onus of proof through its cross-examination of Professor Henderson that, relevantly, it was the Scottish exposure - and not the negligent Whyalla exposure - which was the sole cause of Mr Hamilton’s mesothelioma.  BHP’s fundamental approach is contrary to the High Court authority.

    Significant contribution and Professor Henderson

27. At a purely conceptual level,[43] diseases caused by an agent (physical, chemical or biological) can be classified as either indivisible or divisible.  An indivisible disease may be compared with a digital switch: an agent of a given quantity either causes or does not cause contraction of the disease; where it does cause contraction, continuing exposure does not affect the cause or severity of the disease.  A divisible disease may be compared with an analogue dial: the greater the quantity of the agent, the greater the severity of the disease.

    [43]   It does not matter for present purposes whether in the real world there are any divisible diseases or conversely any indivisible diseases.

28. Still at a purely conceptual level,[44] diseases can be classified as either caused by a single dose (unit or quantum) or by a cumulative dose (multiple units or quanta).

    [44]   It does not matter for present purposes whether in the real world there are any single dose or conversely any cumulative dose diseases.

29. For illustrative purposes, compare a wartime operation.  A single sniper fires a single bullet containing a biological agent at an enemy soldier such that the bullet either penetrates the soldier’s skin or it does not.  If it penetrates, it gives rise to contraction of a disease.  That is analogous to a single dose indivisible disease.  Compare that with a battalion of soldiers that overwhelms an enemy company by sheer numbers.  The battalion’s success is not due to the effect of any one soldier or group of soldiers.  Rather, it is the cumulative result of overwhelming superiority of numbers.  That is analogous to a cumulative dose indivisible disease.

30. While this case is to be decided upon the evidence adduced before the trial Judge and not by reference to the exposition of disease in previous cases, at a purely conceptual level, the following description and examples given by Lord Phillips in Sienkiewicz v Greif (UK) Ltd[45] contain an eloquent exposition:

    Many diseases are caused by the invasion of the body by an outside agent. Some diseases are caused by a single agent. Thus malaria results from a single mosquito bite. The extent of the risk of getting malaria will depend upon the quantity of malarial mosquitoes to which the individual is exposed, but this factor will not affect the manner in which the disease is contracted nor the severity of the disease once it is contracted. The disease has a single, uniform, trigger and is indivisible.

    The contraction of other diseases can be dose related. Ingestion of the agent that causes the disease operates cumulatively so that, after a threshold is passed, it causes the onset of the disease. Lung cancer caused by smoking is an example of such a disease, where the disease itself is indivisible. The severity of the disease, once it has been initiated, is not related to the degree of exposure to cigarette smoke.

    More commonly, diseases where the contraction is dose related are divisible. The agent ingested operates cumulatively first to cause the disease and then to progress the disease. Thus the severity of the disease is related to the quantity of the agent that is ingested. Asbestosis and silicosis are examples of such diseases, as are the conditions of vibration white finger and industrial deafness, although the insults to the body that cause these conditions are not noxious agents. For this reason it is important to distinguish between asbestosis and mesothelioma when considering principles of causation.[46]

    [45] [2011] 2 AC 229.

    [46]   Sienkiewicz v Grief (UK) Ltd [2011] 2 AC 229 at [12]-[14] per Lord Phillips. It does not matter for present purposes whether or not Lord Phillips was correct in assigning malaria, lung cancer and asbestosis etc to the correct categories.

1. BHP’s contention based on risk and probability depends upon its establishing that mesothelioma is a single dose disease.  For the purposes of illustration, assume that malaria is a single dose disease and is contracted anywhere between 10 and 20 days before the onset of symptoms.  Assume that P is exposed to mosquito bites at a constant rate over six days due to D1’s negligence and then at a constant rate over one day due to D2’s negligence (each within 10-20 days before symptoms).  On BHP’s argument, P would succeed on causation against D1 but fail against D2.  BHP contends that the same analysis applies to Mr Hamilton’s exposure to asbestos in Scotland (accounting, on the trial Judge’s findings, for 86 per cent of his total exposure) and his negligent exposure at Whyalla accounting at most[47] for 14 per cent of his total exposure.

   [47]   Because on BHP's contention there was some non-negligent exposure at Whyalla: see above.

2. The trial Judge found, on the basis of his acceptance and understanding of Professor Henderson’s evidence, that mesothelioma is not a single dose disease, that it is dose related and that Mr Hamilton’s exposures at both Scotland and Whyalla operated cumulatively to cause his contraction of the disease.  While the trial Judge’s findings were more comprehensive, his findings are encapsulated in the following passages:

   [Professor Henderson] demonstrated how asbestos participated at a number of different levels over a span of time and the peculiar characteristic of asbestos of persistence of the anthobial fibres over many years together with the role of further episodes of exposure. It reflected the pathogenesis based on what we know about the essential stages. It was the causal explanation of the disease, describing the steps by which asbestos transforms a group of mesothelial cells into a cancer of mesothelial cells.

   …

   … reactive oxygen species (ROS) and reactive nitrogen species (RNS) … are initially liberated because of the interaction between asbestos fibres and the macrophage.  This effected interaction almost immediately with other cells in the near vicinity producing damage.  The effort of the macrophage to ingest the fibre resulted in a generation of showers of free radicals … The scale of fibres present determined the scale of reactive chemicals generated and the scale of damage to the DNA, as well as the biopersistence of the asbestos fibre. It has been calculated this damage would be operative over perhaps 120 generations of mesothelioma cells becoming more abnormal. The time for the entire population of mesothelioma cells to be renewed was six to ten times each year and for an average mesothelial between 180 to 300 generations … Further the promotion and proliferation phases involving resistance to apoptosis and an unknown number of cell generations leading to an expanded and mutative clone of cell. This resulted from the fibre load being supplemented by ongoing exposures over the pre-cancerous period. Then a final event associated with transition from those cells to the mesothelioma and the indivisible injury.

   …

   Because of the lifetime of a generation and the need for so many generations of mesothelial cells, for an average mesothelioma case there was a need for multiple asbestos fibres with their secondary chemical messengers reacting with multiple mesothelial cells over multiple generations of such cells from the point of the initially damaged cell. It is not a matter of a single mutation but new mutations building on top of existing mutations, with stimulation of the cells by both autocrine and heterocrine growth factors. Repair and lethal mutation could occur at all these levels. And importantly further asbestos fibres generated reactive oxygen and species in other chemicals operating further down the mutational chain of events as described in the diagram. This was compounded by the bio-resistance nature of the fibres that can produce effect even decades after their first lodging.

   …

   The cross-examination of Professor Henderson introduced the question of whether additional fibres increased “risk” or actually contributed to the requisite load for triggering the fatal disease. This gave rise to an issue of what Professor Henderson meant irrespective of wording. I have no doubt, given a close examination of all his testimony, that Professor Henderson meant causation not risk. The defendant in contending he meant risk relied on various passages which were ambiguous and yet it failed in my opinion to confront Professor Henderson with the issue. That was however finally resolved.

   …

   The contention that Professor Henderson’s opinion was in terms of “risk” and not “cause” is rejected.

   Each inhalation is not to the point rather periods of exposure are … What was to his mind significant was a continual situation of free radicals caused by the asbestos inducing mutational cascades interacting with multiple mesothelial cells over multiple generations … a significant period of exposure and inhalation clearly contributed.[48]

   [48] [2012] SADC 25 at [92], [96], [97], [98], [99] and [100].

3. BHP has not demonstrated error by the trial Judge in his understanding or acceptance of Professor Henderson’s evidence. 

4. BHP’s primary contention is that, properly understood, Professor Henderson did not characterise mesothelioma as a cumulative dose indivisible disease.  BHP makes the subsidiary contention that Professor Henderson was only saying that additional exposures (and in particular BHP exposure) merely increased the risk of contraction of mesothelioma and did not contribute to the contraction of the disease in the causative sense.  Both the primary and subsidiary contentions should be rejected.  Professor Henderson’s evidence extended over the course of more than a day and needs to be read and understood in its entirety.  The following passages are illustrative of his evidence:

   … in terms of a single-fibre theory for mesothelioma genesis by this sort of thing is – I regard as ridiculous. … The simple fact is, the more … fibres there are present, the greater the number of these reactive chemicals generated from the fibres or in association with them, the greater the probability and extent of damage to the DNA apparatus of the cell, and that these reactions … don’t affect a single generation of cells.  I think we’ve calculated that it probably would extend over perhaps 120 generations of mesothelial cells carrying these mutations and then becoming progressively more abnormal before a final event occurs which transforms the cell into a mesothelioma cell …

   …

   … both for mesothelioma and for other cancers, that they represent singular injuries, that is, all or none injuries; you either develop the cancer or you don’t, and, once you’ve developed the cancer, continued exposure to the event that caused it can’t make it really worse, and, equally, if you withdraw the event or the factor that caused it, it doesn’t reverse it, it’s an irreversible condition.

   …

   … you’re not looking at a single fibre or interacting with a single cell, we’re looking at multiple asbestos fibres, with their secondary chemical messengers reacting with multiple mesothelial cells over multiple generations of mesothelial cells. …

   There could be either fibres resident within the tissues for a long period of time, or fibres newly deposited from further asbestos exposure.  But they will have the same effects in terms of generating reactive oxygen and species in other chemicals.  And that they would also operate further down the line in this mutational chain of events.

   …

   … once you have an additional exposure one cannot argue that that exposure with fibres resident in the pleura is not generating the same sorts of reactive chemicals as the earlier exposures by way of an incremental effect upon them and somehow can be quarantined from the effects of those earlier exposures.  The point is that all exposures contribute – all exposures will contribute to the total burden of asbestos fibres.  The greater the number of fibres, the greater number of the free radicals, the greater the probability those free radicals will induce this mutational cascade interacting with multiple mesothelial cells ultimately over multiple generations … I would say that for each exposure or inhalation of asbestos within a latency interval that each would contribute towards the development of these chemical messages that we’ve been describing.  I do not know of any evidence that an asbestos inhalation would then not be followed by the generation of those free radicals and the mutational events.

   …

   a proportion of each of the episodes of inhaled asbestos fibres will play some role, and that the more fibres there are, the greater the number of chemicals, the greater the number of mutations.

   …

   … the more fibres you have in lung – in pleura tissue, interacting with mesothelial cells, the more chemicals there will be causing genetic injury which will ultimately lead to the mesothelioma …

   … Mr Hamilton’s mesothelioma from which he died was the outcome of all of his identified asbestos exposures, including the three Scottish shipyard exposures, but it is also my opinion that the Whyalla shipyard of [sic] exposure would have made a causal contribution towards the development of his mesothelioma superimposed upon the causal contributions of everything that went before in terms of asbestos exposure.[49]

   [49]   Transcript pages 458-459, 466, 467, 477, 484, 514 and 537.

5. On the one hand, on many occasions Professor Henderson gave evidence that the prospective risk of contracting mesothelioma increased with further exposures.  On the other hand, it is clear from his evidence as a whole (illustrated by the passages quoted in the previous paragraph) that he also gave evidence that, if mesothelioma was contracted, further exposure had contributed in the causal sense.  Those two propositions are not mutually inconsistent.  The trial Judge correctly understood Professor Henderson’s evidence both as to cause or contribution and prospective risk.  He also correctly understood Professor Henderson as characterising mesothelioma as a cumulative dose indivisible disease.

   Discharge of onus of proof

6. Throughout his lengthy cross-examination, Professor Henderson did not give any evidence at all that, or on the basis of which BHP could prove that, Mr Hamilton’s exposure to asbestos resulting from BHP’s negligence did not cause or contribute to his contraction of mesothelioma. Quite simply, BHP failed to discharge the onus of proof resting upon it by operation of section 8(1) of the Act.

   High Court authority

7. In Amaca Pty Ltd v Booth,[50] Mr Booth was an automotive mechanic who was exposed to asbestos dust from brake linings between 1953 and 1983. Between 1953 and 1962, Hardie-Bestos and Hardie-Ferodo brake linings were manufactured by Amaca. Between 1962 and 1983, they were manufactured by Amaba. Seventy per cent of the fibres released from brake linings upon which Mr Booth worked were Hardie-Bestos or Hardie-Ferodo brakes. While the number of brake linings replaced by Mr Booth varied from month to month (ranging from 2 to 12 times a month), the parties apparently proceeded on the basis that the exposure between 1953 and 1983 was linear. On that basis, exposure to Amaca dust accounted for approximately 25 per cent and exposure to Amaba dust accounted for approximately 45 per cent of total exposure from brake linings. In addition, Mr Booth had been exposed to smaller amounts of asbestos dust as a result of home renovations and loading asbestos bags onto trucks earlier in his life. Professor Henderson and other doctors gave expert evidence before the trial Judge. The trial Judge found that mesothelioma was caused cumulatively by the asbestos dust to which Mr Booth had been exposed and that the asbestos derived from each of Amaca and Amaba made a significant contribution towards the development of the mesothelioma. There was no equivalent of section 8(2) of the Act in that case. Mr Booth bore the onus of proof. The trial Judge’s findings were upheld by the Court of Appeal.

   [50] (2011) 246 CLR 36.

8. French CJ, Gummow, Hayne and Crennan JJ (Heydon J dissenting) dismissed the appeals by Amaca and Amaba.  The High Court upheld the Court of Appeal’s decision that the trial Judge had not erred in finding that it had been proved that each of Amaca and Amaba materially contributed to Mr Booth’s mesothelioma.  The decision depended upon the evidence adduced in that case, which differs from the evidence adduced in the present case.  However, the mere fact that Amaca was responsible for less than 25 per cent of the total exposure did not prevent Mr Booth succeeding on the issue of causation as against Amaca.

9. French CJ said:

   It is enough for present purposes to say that an inference of factual causation, as against both Amaca and Amaba, was open on the evidence before the primary judge. The cumulative effect mechanism involving all asbestos exposure in causal contribution to the ultimate development of a mesothelioma had been propounded and was accepted by his Honour. It depended upon an understanding of physiological mechanisms. It did not depend upon the epidemiology. Whether or not medical science in the future vindicates or undermines that theory, is not to the point. That is not a question which can be agitated on these appeals. The cumulative effect mechanism, accepted by his Honour, implicated the products of both Amaca and Amaba in the development of Mr Booth's disease. The primary judge's interpretation of the expert evidence and his conclusions from it, were open as a matter of law.[51]

   [51] Ibid at [51] per CJ.

   and Gummow, Hayne and Crennan JJ said:

   The "but for" criterion of causation proved to be troublesome in various situations in which multiple acts or events led to the plaintiff's injury, for example, where the development of a particular medical condition was the result of multiple conjunctive causal factors. In such cases what may be unclear is the extent to which one of these conjunctive causal factors contributed to that state of affairs. These situations have been addressed by the proposition stated by Lord Watson in Wakelin v London & South Western Railway Co that it is sufficient that the plaintiff prove that the negligence of the defendant "caused or materially contributed to the injury". In that regard, reference may be made to the well-known passage in the speech of Lord Reid in Bonnington Castings Ltd v Wardlaw. Of that case it was said in the joint reasons in Amaca Pty Ltd v Ellis:

   "The issue in Bonnington Castings was whether exposure to silica dust from poorly       maintained equipment caused or contributed to the pursuer's pneumoconiosis,      when other (and much larger) quantities of silica dust were produced by other activities at the pursuer's workplace. Those other activities were conducted without breach of duty. As Lord Reid rightly pointed out, the question in the case was not       what was the most probable source of the pursuer's disease: dust from one source       or the other. The question was whether dust from the poorly maintained equipment    was a cause of his disease when the medical evidence was that pneumoconiosis is   caused by a gradual accumulation of silica particles inhaled over a period of years."

   …

   Mr Booth developed his case in the following steps: (1) he had contracted mesothelioma; (2) the only known cause of that disease is exposure to asbestos; (3) the expert evidence at trial, accepted by the primary judge, was that: (a) exposure to asbestos contributes to the disease; and (b) the prospective risk of contracting the disease increases with the period of significant exposure; (4) Mr Booth had two periods of significant exposure; (5) it is more probable than not that each period of exposure made a material contribution to bodily processes which progressed to the development of the disease.

   …

   It was open to the primary judge to decide that he was "not persuaded that the epidemiological evidence specific to automotive mechanics is adverse to the submission that causation has been proved in this particular case".

   The Court of Appeal, with respect, correctly concluded:

   "Findings as to the cumulative effect of exposure to asbestos were undoubtedly      open. [Mr Booth's] witnesses, including Professor Henderson and Dr Leigh, sought       to reconcile that approach with the epidemiology which suggested there was no    increased risk in the case of brake mechanics. It was open to his Honour to accept their evidence, as he did. The underlying proposition put forward by the appellants,         that the epidemiology was conclusive, in accordance with the principles applicable     to such evidence, did not give rise to a question of law, but to a question of fact,     which his Honour resolved against the appellants."[52]

   [citations omitted]

   Other issues

   [52] Ibid at [70], [83] and [90]-[91] per Gummow, Hayne and Crennan JJ.

10. In WorkCover Corporation v Perre,[53] this Court considered what was required to rebut the statutory presumption of causation created by sections 31(2) and 113(2) of the Workers Rehabilitation and Compensation Act 1986 (SA). Section 113(2) creates a rebuttable presumption that, where a worker suffers noise induced hearing loss and was exposed in employment to noise capable of causing noise induced hearing loss, the whole of the noise induced hearing loss arose out of that employment. Mullighan J (Doyle CJ and Wicks J agreeing) said:

    The worker is required to prove that he has noise-induced hearing loss and that he has been employed in work involving exposure to noise. The burden of proof then shifts to the Corporation or an exempt employer, as the case may be. I shall refer only to the Corporation. It must prove that the hearing loss could not have arisen from the employment.[54]

    [53] (1999) 76 SASR 95.

    [54]   WorkCover Corporation v Perre (1999) 76 SASR 95 at [28] per Mullighan J (Doyle CJ and Wicks J agreeing).

11. If a similar construction were adopted of section 8(1) of the Act, it would require an employer such as BHP to prove that the mesothelioma could not have been caused by the employer’s negligence. However, given the conclusions reached above, it is unnecessary to consider that question. Nor is it necessary to consider the other answers advanced by Mrs Hamilton to BHP’s contentions summarised at [77] and [87] above. Nor is it necessary to consider whether, but for the existence of section 8(1) of the Act, Mrs Hamilton would have discharged the onus of proof of causation under common law principles.

    The cross appeal on damages

12. Mrs Hamilton cross appeals against the trial Judge’s award of $115,000 for pain, suffering and loss of amenities of life on the ground that it is manifestly inadequate having regard to comparable awards in interstate jurisdictions.  Mrs Hamilton contends that an appropriate award in 2012 was in the vicinity of $230,000.  

    Comparative awards

13. An issue of principle is raised on the cross appeal whether regard can be had to comparable first instance awards in courts and tribunals of this State and comparable first instance and appellate awards in other jurisdictions in assessing the adequacy of awards for pain, suffering and loss of amenities of life.[55]

    [55]   No issue arises in relation to the assessment of damages for economic loss, such as loss of earnings, loss of earning capacity and medical costs.  My remarks are confined to the assessment of damages for pain, suffering and loss of amenities of life.

14. An assessment of damages is to be made of the individual injuries and circumstances of the plaintiff and it is inappropriate to apply a tariff.[56]  However, it is appropriate to have regard in a general sense to awards in comparable cases to ensure that the individual award is reasonably proportionate to damages being awarded generally in comparable cases.[57] 

    [56]   Planet Fisheries Pty Ltd v La Rosa (1968) 119 CLR 118 at 124-125 per Barwick CJ, Kitto and Menzies JJ.

    [57]   Carson v John Fairfax & Sons Ltd (1993) 178 CLR 44 at 57-60 per Mason CJ, Deane, Dawson and Gaudron JJ and 72-73 per Brennan J. See also Hirsch v Bennett [1969] SASR 493 at 494 per Bray CJ and 497-499 per Travers and Walters JJ and Packer v Cameron (1989) 54 SASR 246 at 250-251 per Cox J (Mullighan J agreeing) and 257 per Duggan J.

1. The judge dealt with the appellant’s contention that Professor Henderson’s opinion was limited to exacerbation of risk and not causation in the following passages:[192]

   [98]The cross-examination of Professor Henderson introduced the question of whether additional fibres increased “risk” or actually contributed to the requisite load for triggering the fatal disease. This gave rise to an issue of what Professor Henderson meant irrespective of wording. I have no doubt, given a close examination of all his testimony, that Professor Henderson meant causation not risk. The defendant in contending he meant risk relied on various passages which were ambiguous and yet it failed in my opinion to confront Professor Henderson with the issue.[193] That was however finally resolved.[194] The whole point of Exhibit A37 makes it clear that Professor Henderson was not describing risk. Nevertheless it was also his opinion that exposure to asbestos could be expressed in terms of risk of contracting mesothelioma. The two are not incompatible until the cancer actually occurs. He stated:[195]

   … once you have an additional exposure one cannot argue that that exposure with fibres resident in the pleura is not generating the same sort of reactive chemicals as the earlier exposures by way of an incremental effect upon them and somehow can be quarantined from the effects of those earlier exposures. The point is that all exposures contribute – all exposures will contribute to the total burden of asbestos fibres. The greater the number of fibres, the greater number of the free radicals, the greater the probability those free radicals will induce this mutational cascade interacting with multiple mesothelial cells ultimately over multiple generations. … each exposure or inhalation of asbestos within a latency interval … would contribute towards the development of these chemical messages that we’ve been describing.

   …

   [100]Professor Henderson said the diagram Exhibit A37 was an attempt to provide a simplified explanation of the cause of mesothelioma. To achieve explanatory value he had to engage in over simplification of what is a complex series of events.[196]  Each inhalation is not to the point rather periods of exposure are. Also mesothelial cells are motile and move around the pleural cavity adding to the occasions of interacting with oxygen species from deposited asbestos fibres. There was no way of knowing the number of lineal consequences of a series of mutational events in a mesothelioma. What was to his mind significant was a continual situation of free radicals caused by the asbestos inducing mutational cascades interacting with multiple mesothelial cells over multiple generations.[197] The number of needed mutations was unknown. That is the number of products at the end of the chain depicted in the diagram.[198] Nor did this evidence propose every fibre inhaled contributes to mesothelioma. Some of the asbestos fibres inhaled are exhaled, some deposited in the airways and only a small portion translocated to the pleura. But a significant period of exposure and inhalation clearly contributed.[199]

   [192] Hamilton v BHP Billiton Ltd [2012] SADC 25 [98]-[100].

   [193] T 10, 511, 524.

   [194] T 532, 537.

   [195] T 477, also T 514.

   [196] T 479, 482.

   [197] T 479.

   [198] T 480.

   [199] T 484.

2. The appellant’s contentions that Professor Henderson’s evidence did not support a conclusion that the deceased’s exposure to asbestos in Whyalla was not causative should be rejected.  The judge has correctly understood Professor Henderson’s evidence which is to the following effect.  In the prodromal phase, that is before the mutated cells become a mesothelioma, the inhalation of asbestos fibres can be said only to increase the risk of contraction of the disease by increasing the frequency and extent of the showers of free radicals which ultimately cause a mesothelioma through cellular mutation.  However, if mesothelioma is contracted, asbestos fibres which have caused prodromal mutations have played a causative part in its contraction.  Once the mesothelioma has been contracted, the involvement of an asbestos fibre in the production of free radicals which have caused prodromal mutations is causative.  The only remaining question is whether the number and distribution of fibres inhaled from a particular source is such as to allow the conclusion that free radicals generated by those fibres played a part in causing the relevant mutations.  Professor Henderson testified that his opinion that the deceased’s exposure at Whyalla was a significant proportional contribution to the causation of his mesothelioma, meant to convey that there was a “causal contribution effect that is more than undetectably, small, minimal, trivial or immeasurable”.

3. It is clear, on the evidence as a whole, that Professor Henderson’s opinion was that the asbestos inhaled by exposure like that of the deceased’s at Whyalla was sufficient to play a causative role in the model of carcinogenesis which he described.

4. Even if the appellant’s contention that Professor Henderson’s opinion was that the Whyalla exposure created an increased risk, but was not proved to be, on the balance of probabilities, causative, were accepted, his evidence would be sufficient to invoke the presumption in s 8(1). It is a sufficient evidentiary basis for a finding that the Whyalla exposure might have caused or contributed to the deceased’s mesothelioma because his evidence was that the exposure gave rise to the possibility of the deceased developing mesothelioma.

5. I reject the appellant’s submission that the respondent failed to prove that the negligent dust exposure might have caused the deceased’s mesothelioma and accordingly s 8(1) did not come into play. Given the finding of breach of duty, and Professor Henderson’s evidence about the pathogensis of mesothelioma and the effect of cumulative exposures, I am satisfied on the evidence that the asbestos dust to which the deceased was negligently exposed might have caused his mesothelioma. The absence of evidence that might quantify the extent to which the adoption of the alleviating measures might have reduced that exposure does not gainsay the fact of material exposure resulting from the breach.

6. Accordingly, the respondent had established that the deceased’s exposure to asbestos dust at Whyalla, resulting from the appellant’s breach of duty, caused or contributed to his dust disease unless the appellant proved to the contrary. 

7. The appellant contended that the relationship between the inhalation of asbestos dust and the development of mesothelioma is the result of random events which can be expressed in terms of risk or mathematical probability only.  On any view, the balance of mathematical probability was overwhelmingly in favour of the risk to which the Scottish exposure gave rise rather than the risk to which the Whyalla exposure gave rise (and, a fortiori, to which the negligent Whyalla exposure gave rise).  The appellant contended that the mathematical probabilities were sufficiently preponderant so as to discharge any onus borne by the appellant that the likelihood is that the Whyalla exposure (let alone the negligent Whyalla exposure) did not cause or contribute to the development of the deceased’s mesothelioma.  The appellant also sought to rely on the evidence of Mr Rogers, which was rejected by the judge, which it said showed no actual risk to the deceased from the level of his exposure.  Accordingly, it submitted, the statutory presumption is rebutted.

8. I do not accept this submission. 

9. The evidentiary burden which the appellant bore was to prove on the balance of probabilities that the negligent Whyalla exposure was not a causal factor in the deceased developing mesothelioma.  In Amaca Pty Ltd v Ellis[200] the High Court emphasised the converse proposition, in the context where it was not concerned with rebutting a statutory presumption, by reference to the well known passage in the speech of Lord Reid in Bonnington Castings Ltd v Wardlaw[201]:[202]

   The issue in Bonnington Castings was whether exposure to silica dust from poorly maintained equipment caused or contributed to the pursuer’s pneumoconiosis, when other (and much larger) quantities of silica dust were produced by other activities at the pursuer’s workplace.  Those other activities were conducted without breach of duty.  As Lord Reid rightly pointed out, the question in the case was not what was the most probable source of the pursuer’s disease: dust from one source or the other.  The question was whether dust from the poorly maintained equipment was a cause of his disease when the medical evidence was that pneumoconiosis is caused by a gradual accumulation of silica particles inhaled over a period of years. 

   [200] (2010) 240 CLR 111.

   [201] [1956] AC 613 at 621.

   [202] (2010) 240 CLR 111 at 136 [67].

10. For the reasons set out above, I do not consider the evidence proves that the Whyalla exposure was not a cause of the deceased’s dust disease.

11. That proposition informs consideration of whether the appellant rebutted the presumption of causation. I do not consider the evidence proves that the Whyalla exposure, including the negligent Whyalla exposure, was not a cause of the deceased’s dust disease. In my view, the uncontested evidence of Professor Henderson prevented the appellant from discharging the evidentiary burden it bore in rebutting the statutory presumption in s 8(1).

12. For the reasons discussed earlier, the proposition that all asbestos exposure will contribute causally to the ultimate development of mesothelioma is not inconsistent with the proposition that not every asbestos fibre inhaled by the deceased necessarily contributed to his development of mesothelioma.  On the evidence, it is likely that some of the asbestos fibres the deceased inhaled were exhaled, some deposited in the airways, and only a small portion translocated to the pleura.  But the aetiology of mesothelioma, as explained in the evidence of Professor Henderson referred to above, leads to two important conclusions.  First, the probability of developing mesothelioma will be influenced by the number of fibres inhaled, during a relevant period, interacting with mesothelial cells over multiple periods of time.  Accordingly, the greater the number of fibres which are inhaled, the greater the probability of developing mesothelioma.  Second, as a result, you cannot exclude the negligent Whyalla exposure as having contributed in a relevant causal sense, to the development of the deceased’s mesothelioma, unless the evidence positively establishes that the exposure was so insignificant as to satisfy the de minimus principle.  Proof that the Scottish exposure was preponderantly more extensive than the negligent Whyalla exposure, does not attract the de minimus principle in the case of the deceased.  The evidence of Professor Henderson was that the exposure was material. 

13. I do not accept that the evidence of Mr Rogers contradicts his opinion.  In my view, it was beyond the expertise of Mr Rogers, as an occupational hygienist, to contradict Professor Henderson’s evidence on this topic.  Mr Rogers’ evidence amounted to a retrospective estimate of the relative exposure of the deceased to asbestos fibres in the course of his work in Scotland and in Whyalla.  The analysis involved various assumptions about exposure frequency and duration which rendered the evidence problematic.  Like the judge, I harbour real reservations as to the confidence the finder of fact could have in relation to the accuracy of this analysis.  In any event, I am not satisfied that it provides a basis upon which this Court should find that the judge was in error in failing to find that the extent of the Scottish exposure was so great that the Court should dismiss as insignificant the proposition that the negligent Whyalla exposure, could not have contributed to the development of the deceased’s mesothelioma.  After all, as Heydon J observed in Amaca Pty Ltd v Booth[203] mesothelioma can be caused by very brief intense exposures.  This observation is in accord with the evidence at trial of Professor Henderson.[204]

    [203] (2011) 246 CLR 36 at 191.

    [204] Professor Henderson’s report, 19 September 2007, at p  11-12.

14. Accordingly, I find that the statutory presumption in favour of causation was not rebutted.

15. This conclusion renders unnecessary consideration of whether the respondent proved on the balance of probabilities that the negligent Whyalla exposure caused or contributed to the development of the deceased’s mesothelioma or mild asbestosis. 

    Cross-appeal

16. The respondent[205] brings a cross-appeal against the award of $115,000 for pain, suffering and loss of amenities. 

    [205] For the sake of convenience, I will refer to the cross-appellant as the respondent and the respondent to the cross-appeal as the appellant.

17. The respondent submits that it is appropriate for this Court to review the prevailing level of damages awards made in South Australia in mesothelioma cases, having regard to awards made interstate.  On this basis, she submits that the award is manifestly inadequate. 

18. The appellant submits that the cross-appeal should be dismissed.  The appellant submits that the trial judge’s award is in line with awards of general damages in comparable cases in this State and which at trial the respondent accepted as the benchmark, having regard to the award of $100,000 for general damages made in Ewins v BHP Billiton Ltd.[206]  It submits that the Court would be wrong in principle to have regard to comparable awards.  If, on the other hand, the Court is to do so, it should confine its consideration to awards by this Court and not to the awards of the superior courts of other jurisdictions, and especially not the awards of inferior courts or tribunals of other jurisdictions.

    [206] (2005) 91 SASR 303.

19. In Ewins v BHP Billiton Ltd,[207] this Court accepted the general proposition that an award of damages must be made having regard to the general level of damages awarded in this State, citing Packer v Cameron.[208]  However, Doyle CJ noted that the level of awards in other states is not irrelevant.[209]  His Honour referred to the Full Court’s judgment in Chakravarti v Advertiser Newspapers Ltd,[210] which held that the level of damages awarded for defamation should be increased, having regard to the level of awards in other states.  While Doyle CJ in Ewins nonetheless found that the general level of awards in South Australia must be his primary guide in fixing an award of damages for pain, suffering and loss of amenities in that case, which was a mesothelioma case, that was on the basis that he was hearing the claim at first instance.  As the former Chief Justice observed, it is the function of the Full Court, and not of a single judge, to decide whether the general level of damages should be increased, having regard to approaches taken in other courts or states, citing Chakravarti.[211]

    [207] (2005) 91 SASR 303.

    [208] (1989) 54 SASR 246 at 250-251.

    [209] (2005) 91 SASR 303 at 310-311 [63].

    [210] (1998) 72 SASR 361.

    [211] (2005) 91 SASR 303 at 312 [71].

20. There is no principle that the general level of awards of damages should be consistent between jurisdictions.  Nonetheless, an award of damages for pain, suffering and loss of amenities differs from an award of damages for loss of earning capacity.  There is less reason to place differing monetary values on the experience of injured persons in different jurisdictions based on wage levels, earning power, or property values.  It is appropriate to have regard to awards in other jurisdictions to ensure that, in giving weight to current general ideas of fairness and moderation, there is not a glaring inconsistency between the value courts in this State place on an injured person’s pain and suffering compared to the value placed on a comparable experience in other jurisdictions. 

21. In my view, it is appropriate this Court undertakes such a review.  I reject the appellant’s submission to the contrary.  While the High Court in Planet Fisheries Pty Ltd v La Rosa[212] disapproved of tariffs in the assessment of damages for personal injury and emphasised the need to focus on the circumstances of the particular plaintiff, Chakravarti establishes that where the Full Court is considering the adequacy of a particular award, it is permissible to have regard to comparable awards in other jurisdictions to determine whether the Full Court should increase the award under review to indicate to the courts of this State an appropriate level of damages. 

    [212] (1968) 119 CLR 118.

22. In Lowes v Amaca Pty Ltd,[213] Corboy J of the Supreme Court of Western Australia undertook a review of recent awards of damages for pain and suffering for mesothelioma claims by that Court, the Dust Diseases Tribunal of New South Wales and the ACT Supreme Court. The awards made by the Supreme Court of Western Australia over the ten years preceding that judgment ranged from $130,000 to $180,000. The awards made by the Dust Diseases Tribunal of New South Wales over the preceding two years ranged from $250,000 to $290,000. In Parkinson v Lend Lease Securities and Investments Pty Ltd,[214] the ACT Supreme Court made an award of general damages of $300,000.

    [213] [2011] WASC 287.

    [214] (2010) 4 ACTLR 213.

23. The particulars of the cases reviewed by Corboy J were:[215]

    [215] [2011] WASC 287 at [815]-[818].

    (a)Easther v Amaca Pty Ltd (Formerly James Hardie & Coy Pty Ltd):[216] a 67 year old plaintiff with mesothelioma: general damages $130,000; loss of life expectancy $15,000;

    [216] [2001] WASC 328.

    (b)McGilvray v Amaca Pty Ltd (Formerly James Hardie & Coy Pty Ltd):[217] a 54 year old plaintiff with mesothelioma; general damages $160,000: loss of life expectancy $15,000;

    (c)Misiani v Welshpool Engineering Pty Ltd (in liq):[218]a 54 year old plaintiff with mesothelioma; general damages $150,000: loss of life expectancy $15,000;

    (d)Ellis, Executor of the Estate of Paul Steven Cotton (Dec) v The State of South Australia:[219]  a 43 year old plaintiff with lung cancer: general damages $150,000; loss of life expectancy $15,000;

    (e)Hannell v Amaca Pty Ltd:[220] a 64 year old plaintiff with mesothelioma: general damages $180,000; loss of life expectancy $15,000;

    (f)Kirkpatrick v Babcock Australia Pty Ltd:[221] a 61 year old plaintiff having an illness of approximately 2½ years duration and uncertain prognosis; treatment included a thoracotomy, a pleurectomy, chemotherapy and radiotherapy; general damages, $250,000;

    (g)Mooney v Amaca Pty Ltd:[222] a 59 year old plaintiff having endured symptoms for 4½ years; treatment included chemotherapy; general damages, $290,000;

    (h)Roberts v Amaca Pty Ltd:[223]  a 64 year old plaintiff having endured symptoms for 4 to 5½ years; treatment included chemotherapy; general damages, $275,000;

    (i)Booth v Amaca Pty Ltd & Anor:[224] a 70 year old plaintiff having endured symptoms for approximately two years; no history of surgical or other medical intervention referred to in the judgment; general damages, $250,000;

    (j)Parkinson v Lend Lease Securities and Investments Pty Ltd:[225] a 72 year old plaintiff having endured symptoms for approximately six years; surgical intervention and radiation and chemotherapy; general damages, $300,000;

    (k)Wall v Cooper:[226]  pain syndrome suffered after leg wound became infected and skin grafting broke down.  Severe and excruciating pain not abating with time.  Plaintiff forced to cease work and left with a 'very limited existence' and dependence on heavy doses of morphine based painkillers.  $450,000 for general damages.[227]

    [217] [2001] WASC 345.

    [218] [2003] WASC 263.

    [219] [2006] WASC 270.

    [220] [2006] WASC 310.

    [221] [2009] NSWDDT 4.

    [222] [2009] NSWDDT 23.

    [223] [2009] NSWDDT 28.

    [224] [2010] NSWDDT 8.

    [225] (2010) 4 ACTLR 213.

    [226] (2006) 43 SR (WA) 69.

    [227] Appeal dismissed: Wall v Cooper [2008] WASCA 53.

1. Since this cross-appeal was argued, the New South Wales Dust Diseases Tribunal has delivered judgment in Perez v The State of New South Wales.[228]  The Tribunal made an award of general damages in the sum of $290,000 to the plaintiff.  The Tribunal found that the 78 year old plaintiff suffered from mesothelioma, the symptoms of which had first manifested in May 2012.  The plaintiff had been treated with radiation, pleural taps, pleurodesis and chemotherapy.  The Tribunal found he had suffered considerable pain, with two prolonged periods of hospitalisation, and chemotherapy with its usual side effects.  At the time judgment was delivered, the plaintiff had a life expectancy of six months.

   [228] [2013] NSWDDT 1.

2. In considering whether the level of damages awarded in this instance is manifestly inadequate, I accept the submission of the appellant that it is appropriate to confine a consideration of what constitutes an appropriate award, determined by reference to current general ideas of fairness and moderation, to comparable awards of damages for terminal disease, including, but not limited to, mesothelioma.  Consideration of awards of general damages for other serious injury is likely to prove unhelpful as a relevant comparator, particular where they might involve awards for injuries which might leave the plaintiff with the prospect of many decades of life with a serious and incapacitating disability.

3. I would reject, however, the appellant’s submission that the Court, in undertaking a review of damages awards in other jurisdictions, should ignore decisions of inferior courts or tribunals, such as the Dust Diseases Tribunal of New South Wales.  While it is the case that those awards have not, for some years, been subject to appeal to the New South Wales Court of Appeal, that is a factor to be weighed by this Court in considering the appropriateness of the level of awards for mesothelioma in this State.

4. It is nearly eight years since Ewins was decided.  In Amaca Pty Ltd v King,[229] the Victorian Court of Appeal, citing with approval the judgment of our Full Court in Joyce v Pioneer Tourist Coaches Pty Ltd,[230] noted that, insomuch as contemporary society pays and receives vastly greater amounts of remuneration than a generation ago (even allowing for inflation), and speaks of the importance of the quality of life to an extent not before contemplated, it cannot be doubted that modern society places a higher value on the loss of enjoyment of life and the compensation of pain and suffering than was then the case in the past. 

   [229] [2011] VSCA 447 at [177].

   [230] [1969] SASR 501 at 503.

5. In Amaca Pty Ltd v King,[231] the Victorian Court of Appeal, in a mesothelioma case, dismissed an appeal against a jury verdict of $730,000 for pain and suffering and loss of enjoyment of life on the ground that it was manifestly excessive.  It did so after reviewing awards in that State and other jurisdictions.[232] 

   [231] [2011] VSCA 447.

   [232] [2011] VSCA 447 at [175]-[179].

6. I note that in Perez v The State of New South Wales,[233] the New South Wales Dust Diseases Tribunal rejected the plaintiff’s submission that in awarding general damages it should have regard to the jury’s verdict in Amaca Pty Ltd v King.[234]

   [233] [2013] NSWDDT 1 at [10].

   [234] [2011] VSCA 447.

7. There do not appear to have been any recently reported awards of damages for mesothelioma in Queensland, Tasmania or the Northern Territory.

8. In my view, having considered damages awarded in other cases involving mesothelioma over the past decade or so, I do not consider that the award made in Ewins any longer represents a fair and moderate award of damages for cases of the kind that the circumstances of this case involve. 

9. As I have noted, the deceased was born in 1940.  He was diagnosed with mild asbestosis in 2005.  In October 2006 he commenced to suffer from breathlessness.  The judge found that Christmas 2006 was a bad time.  His general activities and regimes came to an end.  The diagnosis of mesothelioma was made in February 2007. This was distressing.  He was in great pain for the last months of his life.  He endured these afflictions stoically.  He died in August 2007.

10. In my view, the award of $115,000 is manifestly inadequate.  I would increase the award to $190,000.  I consider such an award to be proportionate to the injury suffered by the deceased.  In reaching this consideration I am influenced by the disparity between the level of award of damages under this head, reflected in Ewins, and the level of awards in mesothelioma cases in other jurisdictions.  This Court should adjust the level of awards for mesothelioma cases in this State. 

11. I would hear the parties further as to the consequences of my decision on the award of interest. 

    Conclusion

12. I would dismiss the appeal.

13. I would allow the cross-appeal.  I would set aside the award of damages for pain, suffering and the loss of amenities and, in lieu thereof, enter an award under that head of $190,000.

14. I would hear the parties further as to interest and the terms of final orders.