Plaintiff v Firstnamed Defendant

2 On 7 July 2007 he suffered serious injury to his right knee when carrying out maintenance work within a piece of plant known as the 'Blow Off Brush Station' ('the brush station') at the Portland Aluminium Smelter.

3 At that time Silcar was retained by the second defendant ('Alcoa') to carry out recurrent maintenance works at the smelter and part of those works included inspecting (and if necessary replacing) brushes used to brush 'bath' from anodes at one point in the production line.

4 On the day in question Fennell was assigned to inspect the brushes and make any necessary consequential repairs together with an apprentice named Lipscombe. Fennell had not done the job before. The job was assigned to Fennell by Silcar at a 'toolbox meeting' which took place in a 'smoko' shed adjacent to the plant at the beginning of the working day. He was given a job pack of documents prepared by Alcoa which described the job to be done, identified hazards associated with it and recorded necessary procedures.

5 The brush station was contained within a large steel cabinet through which the anodes passed suspended on rods from an overhead line. A conveyer in the base of the cabinet removed waste displaced by the brushes. The general appearance of the station is shown in a photograph tendered in evidence.

6 The dimensions of the brush station are shown in an elevation drawing comprised in one of the documents tendered in evidence.

7 The Court had the benefit of a view of the brush station from the exterior.

8 As the photograph and elevation drawing demonstrate the brush station could be entered from two doors on its northern side being an eastern door ('door 1') reached by a set of stairs and access platform and a western door ('door 2') reached by moving further west along the same access platform. The doors were opened and closed with two levers: one near the top and one near the base of the door. Adjacent to each door there was a confined space warning bearing a confined space number. These warnings have since been replaced with a restricted space warning as a result of a re-classification.

9 Fennell had to obtain a confined space permit before entering the brush station because there was a risk that the atmospheric conditions within it were dangerous.

10 Fennell's evidence was that he waited until the atmosphere within the confined space had been tested by Alcoa personnel and then entered the brush station through door 1. As he recollects it door 2 was not open and he was not aware that there was a door 2 he could use.

11 When Fennell looked through door 1 he could see that there was a 'grizzly' or open spaced metal grill at floor level relative to the door. He then made enquiries of a Silcar employee (Michael Telfer) as to what he should do to enter the brush station safely and was told to lay down sheets of plywood (kept next to the brush station). He did so and then entered the brush station with a torch. He first turned to his left and inspected a set of 'blow off' air nozzles for wear and tear and damage. He then turned to his right and crawled approximately three metres up the line within the brush station to inspect the brushes. The brushes comprised a bank of four with two on each side of the line down which the anodes pass. They were angled in from above towards the centre. They had wire bristles about 300 mm long around the perimeter of each brush, comprised in a single row of double bunch bristles. The bottom of the brushes was at about knee height above the floor on the grizzly.

12 Having reached the brushes Fennell checked the written instruction for the job and found that he was required to check the brush 'measurement'. He turned around and crawled back out of the brush station and asked an Alcoa supervisor (Derek Hastings) how he could check the measurement when the written instruction did not specify a relevant dimension. He was told in effect to simply check that the position of the brushes looked OK.

13 Fennell then re-entered the brush station, again through door 1, and crawled back to the brushes. On reaching them, he knelt before them and again inspected them before turning through 180° on his knees in order to crawl back out. In turning, he severely injured the ligaments of his right knee. The seriousness of the injury was aggravated by the fact that surgery to his knee many years before had left him vulnerable to further injury.

14 Fennell issued proceedings in this Court claiming damages for personal injury alleging that his injury was caused by the negligence or breach of statutory duty of the defendants. He called evidence bearing on the issue of liability from Mr Dunsmuir, a handyman and qualified fitter and turner who worked at the smelter for approximately 15 years ending in late 2005;[3] Mr Telfer, who worked at the smelter for approximately 21 years ending in 2009;[4] and Mr Lucas, a retired maintenance fitter who worked at the smelter from about 1985 to 2011.[5] Each of them had carried out routine maintenance on the brush station at some point in their employment, whether under the employment of Silcar or another contractor.

15 In turn, the first defendant called evidence from Mr McIlroy, who in July 2007 was a supervisor employed by Silcar,[6] and Mr Nash, who in July 2007 was the occupational health and safety coordinator for Silcar,[7] and the second defendant called evidence from a Mr Clarke who in July 2007 was a safety department health resource officer for Alcoa.[8]

16 In the course of trial the defendants first agreed the plaintiff's quantum in the sum of $850,000.

17 They further abandoned allegations of contributory negligence.

18 Alcoa then settled with the plaintiff on the fourth day of the trial and the plaintiff's claim against it was dismissed by consent.

19 On the fifth day of the trial Silcar settled with the plaintiff and the plaintiff's claim against it was also dismissed by consent. This left outstanding the issue of contribution as between the defendants. Each defendant had filed and served notices of contribution and indemnity pursuant to s 23B(1) of the Wrongs Act 1958.[9]

20 Silcar and Alcoa now seek to continue to claim contribution pursuant to s 23B(4).[10]

21 Such a claim may involve issues beyond the ascertainment of the 'extent of [the other defendant's] responsibility for the damage'.[11]

22 Nevertheless the defendants now seek a determination from the Court restricted to apportionment of responsibility for the injury to Fennell.

23 In order to assess that responsibility it is necessary to consider both the extent to which breach of duty caused the injury to Fennell (if any) and the relative culpability of each of the defendants in respect of any such breach.

24 Silcar owed Mr Fennell the non-delegable duty of care described by the High Court in Czatyrko v Edith Cowan University.[12]

25 The non-delegability of the duty was relevant because Silcar could not in law pass responsibility for the performance of its duty back to Alcoa.

26 The duty of care included in particular a duty to provide adequate supervision and instruction as part of a safe system of work. In O'Connor v Commissioner for Government Transport[13] the High Court put it this way:

The defendant as employer was of course under a duty, by his servants and agents, to take reasonable care for the safety of the deceased by providing proper and adequate means of carrying out his work without unnecessary risk, by warning him of unusual or unexpected risks, and by instructing him in the performance of his work where instructions might reasonably be thought to be required to secure him from danger of injury.

27 For completeness I should add that, insofar as the basic facts of the accident in which Mr Fennell was injured might be said to suggest some inadvertence on his part, that did not relieve Silcar of its duty of care.

28 In McLean v Tedman,[14] Mason, Wilson, Brennan and Dawson JJ said:

The employer's obligation in this respect cannot be restricted to the provision of a system which safeguards the employee from all foreseeable risks of injury except those which arise from his own inadvertence or negligence. There are many employment situations in which the risk of injury to the employee is negligible so long as the employee executes his work without inadvertence and takes reasonable care for his own safety. In these situations the possibility that the employee will act inadvertently or without taking reasonable care may give rise to a foreseeable risk of injury. In accordance with well settled principle the employer is bound to take care to avoid such a risk.[15]

29 Counsel for Alcoa submitted that Silcar's non-delegable duty of care relevantly included a duty to provide a safe system of work; to ensure reasonable care was taken in the training, instruction and direction given to employees; to provide competent, trained, instructed fellow employees; and to provide ongoing supervision in the course of employment. Further, in exercising its duty, Silcar must take into account other employees' thoughtlessness, inadvertence and carelessness.

30 Counsel for Alcoa contended that liability for the incident was completely attributable to the fact that neither Mr Fennell nor the apprentice who assisted him knew of the practice of using both doors in performing the job. Counsel pointed to Messrs McIlroy, Nash and Clarke's awareness of door 2, and contended that there was no problem with brush station when entered in this way. This was borne out by the fact that nobody inspecting had been injured or encountered relevant problems in doing that job previously. Had Mr Fennell known that he was supposed to use door 2, even if it had been closed he could have opened it himself or arranged for it to be opened. However, Silcar did not check whether Mr Fennell had performed the job before or instruct him as to using door 2.

31 In commencing their final address, counsel for Silcar conceded much of the force of Alcoa's submissions. In particular, counsel conceded that Alcoa has 'the higher duty as the direct employer'; that Mr Fennell ought to have been trained properly in the job; and that it is relevant that it was his first time performing the job.

32 In the circumstances, I am satisfied that Silcar breached its duty of care to Fennell by failing to properly instruct and supervise him when:

(a) Fennell had not done the job before and was not assisted by an experienced employee;

(b) the written instructions did not make access arrangements to the brush station clear;

(d) Fennell made enquiries which should have alerted his Silcar supervisor to the fact that he was unfamiliar with access arrangements;

(e) Fennell was permitted to crawl from door 1 up to the brushes and then make a 180° turn (in the dark) on his knees on the plywood floor holding a torch in one hand before crawling back; and

(f) this manoeuvre was unnecessary if Fennell had obtained access through door 2 immediately adjacent to the brushes.

33 The failure to properly instruct and supervise Fennell in these circumstances was a cause of the plaintiff's injury.

34 The question of Alcoa's breach of duty (if any) is more difficult. Alcoa owed the plaintiff a general duty of care.

35 In Leighton Contractors Pty Ltd v Fox,[16] French CJ, Gummow, Hayne, Heydon and Bell JJ affirmed that the common law does not impose a duty of care on principals in respect of independent contractors of the same kind as that which is owed to employees. The Court endorsed the statement of principle by Brennan J in Stevens v Brobribb Saw Milling Company Pty Ltd:[17]

An entrepreneur who organises an activity involving a risk of injury to those engaged in it is under a duty to use reasonable care in organising the activity to avoid or minimise that risk, and that duty is imposed whether or not the entrepreneur is under a further duty of care to servants employed by him to carry out that activity. The entrepreneur's duty arises simply because he is creating the risk and his duty is more limited than the duty owed by an employer to an employee. The duty to use reasonable care in organising an activity does not import a duty to avoid any risk of injury; it imports a duty to use reasonable care to avoid unnecessary risks of injury and to minimise other risks of injury. It does not import a duty to retain control of working systems if it is reasonable to engage the services of independent contractors who are competent themselves to control their system of work without supervision by the entrepreneur. The circumstances may make it necessary for the entrepreneur to retain and exercise a supervisory power or to prescribe the respective areas of responsibility of independent contractors if confusion about those areas involves a risk of injury. But once the activity has been organised and its operation is in the hands of independent contractors, liability for negligence by them within the area of their responsibility is not borne vicariously by the entrepreneur. If there is no failure to take reasonable care in the employment of independent contractors competent to control their own systems of work, or in not retaining a supervisory power or in leaving undefined the contractors' respective areas of responsibility, the entrepreneur is not liable for damage caused merely by a negligent failure of an independent contractor to adopt or follow a safe system of work either within his area of responsibility or in an area of shared responsibility.

36 In such a case the principal may owe a duty to an employee of the independent contract to exercise reasonable care in the supervision of that employee's work because there has been an assumption of responsibility for that supervision by the principal contractor.[18]

37 Alcoa was entitled to put in place a system of maintenance under which it placed the primary responsibility for the implementation of maintenance work upon an independent contractor. Nevertheless it owed a duty of care to Mr Fennell in respect of those elements of the system of work over which it retained control.

38 In final address counsel placed particular emphasis on alleged confusion and inadequacies in the work pack documentation provided by Alcoa and alleged failure to satisfactorily provide proper access to the confined space.

39 Ultimately I have reached the view Alcoa must bear some responsibility for Mr Fennell's injury because it breached its duty of care to him in the following respects:

(a) the work pack documents prepared by Alcoa purported to deal with safety issues and made some reference to access considerations but were confusing and inadequate;

(b) Alcoa did not provide safe access through door 2; and

(c) the Alcoa supervisor present in the area did not adequately supervise access to the brush station in circumstances where the use of the access doors was ultimately controlled by Alcoa.

Each of these conclusions is not free from controversy and it is necessary to elaborate my reasons for them.

40 First, Alcoa took primary responsibility for the description of the job by means of the work pack. The paperwork provided to Fennell was only able to be replicated in part before the Court but the evidence established that it included the following:

• a confined space Hazard Identification and Risk Assessment ('HIRA');

41 A sample work planning form[19] produced in evidence was said to be of the effect of the one utilised.

42 It is significant for present purposes that it commences by listing the leadership group associated with the job. These comprised both Alcoa and Silcar personnel.

43 The form provided for a description of the work to be inserted together with its location and date. It then provided for the ATL or back-up to sign off to commence the work and for the CTL or back-up to also sign off to commence the work. There was a pre-job hazard checklist, a list of hazard identification and control measures, provision for standard work instructions and standard isolation procedures and provision for a participant review. Finally, there was a work completion checklist and provision for the CTL and ATL to sign off. The form thus made clear to the worker that supervision was to be both by Silcar and Alcoa.

44 A standard instruction for the 'rodding - brush station 28 day mechanical inspection' was also produced in evidence.[20] It was last modified on 4 December 2007 ie after the relevant date. But the evidence established that it was in a generally similar form to documentation supplied to Fennell. The standard instruction specified the second task to be undertaken as follows:[21]

Brush station - Bath reclaim Est. task time 60 Off Line

Inspect:

1. Venturi, venturi mounts and associated pipe work for wear, damage cracks, fasteners and fastener security.

2. All 4 brushes for wear, damage, security and presence.

3. Air manifolds and nozzles for wear, damage alignment and security (Replace nozzles as required)

4. Set to correct height. (550 MM from floor of station to centreline of brush)

Acceptable Limits 1. Venturi, venturi mounts and associated pipe work, no wear, no damage, no cracks, no missing fasteners and fasteners secure

2. All 4 brushes, no wear, no damage, secure and brushes not missing.

3. Air manifolds and nozzles, no wear, no damage, aligned and secure (nozzles replaced as required)

4. Height set

Corrective action Correct fault immediately if possible or inform Supervisor to raise a work request

This task will next be due 28 days

45 It also provided for comments to be inserted by workers undertaking the job.

46 A further document from the same date headed 'Maintenance Standard Work Instruction' described the work as follows:[22]

To inspect the four (4) brushes in the blow off cabinet along with blow off nozzles and venturis and complete any minor repairs

47 The form went on to provide for listings of special tools and equipment required, materials required and additional personal protective equipment. No specification was made under these headings. It then provided for 'isolations'.[23]

SIP_232_BTH-R_M03 Horizontal Flailing Stn & Brush Stn

48 Under the heading 'permits required' the document listed:[24]

49 It then provided a generic hazard identification form which flagged the need for some pre-job hazards to be checked. In particular, it was necessary to complete a visual inspection of the work area prior to work start to identify any potential hazards and to remove or minimise any hazards. Under the heading 'pre-work hazard review' the document further provided:[25]

1. Read the scope of work and pre work requirements first.
2. At the work site carry out a pre-job review of hazards and environmental impacts using the pre identified hazards already listed in the MSWI and a work planning form to identify any new or temporary hazards and environment impacts.
3. If you are unsure of any aspects of this task or the work area seek advice from an experienced person.
4. For new hazards, tick the appropriate box in the hazard identification form. Or, if no hazard description matches, tick the other (description) box and write in the new hazard.
5. Write up new hazard and environmental impacts and countermeasure in the blank spaces provided in the work planning form.
6. Implement all countermeasures before commencing work.

50 Pre-work required was stated to be:[26]

9: PRE WORK REQUIRED

Pre work

Ensure that equipment is available to be taken off line

Bath cleaning is free of bars

51 It then listed tasks to be undertaken upon completion of the job.

52 It may be noted that none of this documentation specified that the brushes were to be accessed from door number 2. Further, the confined space permit referred to in the standard work instruction was said to relate to space CS - 21 - 191 only.

53 The relevant HIRA (last modified in October 2006) was produced in evidence and is an eleven page document. It first described the unit to which it relates.[27]

UNIT BLOW OFF STATION, VERTICAL FLAIL STATION, HORIZONTAL FLAIL STATION

CONFINED SPACE IDENTIFICATION CS-21-191, CS-21-192

54 It then set out a description of the confined space.[28]

1. Description of the confined space:

The equipment consists of flailing chains that remove material from a suspended load. The Horizontal Flail Station also includes four (4) rotating brushes and an air blow off manifold. The equipment has a steel grizzly floor with a drop of approximately 2 metres to a conveyer belt.

55 It listed possible tasks to be performed in the confined space - atmospheric testing, inspection, maintenance and housekeeping.

56 It set out a sequence of job steps.[29]

3 Sequence of Job Steps:

a) Contact Shift Facilitator. g) Complete task(s).

b) Clear all suspended Butts/Bars from the area. h) Close permit(s) & De-isolate the

equipment.

c) Air Quality Test. i) Notify Shift Facilitator that the work

has been completed.

d) Confined Space Permit issued/Hot Work

Permit if required.

e) Isolate equipment per written or standing

isolation procedure.

f) Refer to relevant S.W.I for Task(s). If no

S.W.I. available a Hazard Assessment Form

shall be filled in.

57 It set out a hazard identification checklist noting the presence of hazardous substances constituted by Hall Cell Bath and potentially explosive dust constituted by carbon dust. It also noted under the heading 'Toxic gases, vapours, mists, dust':[30]

Hall Cell Bath Dust, Carbon Dust, Welding Fumes, and products of combustion generated during welding activities / Hot Work. If Hall Cell Bath is exposed to high temperature, Hydrogen Fluoride will evolve.

58 Under the heading 'Plant and process hazards' it recorded in respect of mechanical hazards:[31]

Flailing chains - Brushes - Grizzly Floor - Air Manifold. Use Duck Boards on Grizzly where possible.

60 Under the heading 'Environment' it stated that portable lighting was required.

61 Under the heading 'Safety Equipment/Procedure Requirements' it provided for work crew size and stated that an attendant was required outside the confined space.

62 It next relevantly provided for atmospheric testing and required testing for oxygen and explosive gases. It stated that ventilation was to be natural 'doors open and forced-dust collection system'.

63 Under the heading 'Hazards associated with the rescue' it noted possible atmospheric hazards - hall cell bath dust, carbon dust, and possible content hazards - bath materials. The HIRA further noted that it was required to be revised at least annually and sequential revisions over a period of four years were noted.

64 Two confined space rescue evaluations were also included in the HIRA. The first related to space number CS - 21 - 191 'Equipment Name: Butt Blow Off and Horizontal Flailing Station' and the task or job 'Atmospheric Testing, Inspection, Maintenance, Housekeeping'. It referred back to a specific standard work instruction - 'SWI - PA021 - SMS - GEN - 0003'. It noted the location of the space in the rodding room, the position of the equipment at the east end of the rodding room, and the fact that access to the space was 'Through the two doors 400mm wide x 1500mm high'. The description of the confined space was:[32]

This is an enclosed area 2M high by 2M wide above a belt conveyer. There is a grizzly that is to be covered with ply board before anyone can enter.

65 A further confined space rescue evaluation relates to space number CS - 21 - 192 'Equipment name: Vertical Flailing Station'. The task or job is named in the same way as the previous rescue evaluation and the standard work instruction number referred to is the same as that for the previous rescue evaluation. The location of the space is again stated to be in the rodding room but the position of the equipment is described as 'South side of the Rodding Room at ground level between New and old bear claws'. Access to the space is described as 'At the East and West ends opening 1600mm in height approximately 1000mm wide'. The description of the space is: '2M x 3M square, 2.5 high to floor level with a grate floor. Bath material from anodes falls onto BH-O2-BC which runs below. If entry inside is required the floor requires ply to be placed on grate opening.'[33]

66 The documentation does not make clear whether the brush station is to be regarded as comprised in CS - 21 - 191 alone or CS - 21 - 191 and 192. Silcar called evidence from Mr Nash who was employed at the time Mr Fennell was injured. Mr Nash was cross-examined on behalf of Alcoa on the basis that the brush station was to be understood to be (and was in fact) wholly within CS - 21 - 191. When Alcoa itself called evidence, however, its own witness, Mr Clarke, gave evidence that CS - 21 - 191 was behind door 1 and CS - 21 - 192 was behind door 2. In other words, the brushes were in CS - 21 - 192.

67 In my view, the contradiction which emerged in Alcoa's case demonstrates that the work pack did not make clear access to the brushes (as distinct from the blow-off vents) was to be via door 2. A reasonably clear set of job instructions would have done this.

68 Secondly, Mr Fennell described the sequence of work as requiring Alcoa personnel to undertake confined space testing and tag the door before he entered the space.

69 I accept that this is what happened. It was the testing and consequent opening of door 1 which gave Fennell access to the space. Although it is not clear precisely how it came about I further accept on the balance of probabilities that door 2 was not open when Fennell was given access to the brush station. As Silcar submits, if it were open then surely Fennell would have used it and furthermore the light through the door would have created an environment entirely different from the one in which he crawled up to the brushes in the dark.

70 The confined space testing plan for CS - 21 - 191, 192 tendered in evidence makes clear both doors should be opened and the space behind them tested together. Testing locations are indicated on the elevation plan which I have included at the outset of these reasons.[34] Mr Clarke's evidence was that it was Silcar employees who would open the door and then leave the brush station to ventilate for about an hour or so before testing. Whoever initially opened the doors I accept the evidence of Fennell that before he could and did commence work Alcoa personnel undertook testing and permitted him to enter door 1. A confined space permit form was tendered in evidence and it required sign-off before it could be utilised. The entry supervisor was required to state that he had reviewed all procedures and documentation with entrants and attendants listed below and 'consider[ed] the confined space safe for entry to complete the tasks identified on the permit'.[35] The authorised entrants/attendants were specifically required to be listed. McIlroy said of the documentation provided to the worker:

it had a provision on the front for a confined space permit and a space for everybody involved in the task to sign in as a participant in the review of the work pack to perform the work.

yeah, all the regulations were met and confined space things, permit and all that, were all on that blue form ...

72 The undertaking of testing in the sequence described by Fennell accords with the sequence set out on the HIRA which is the only truly contemporaneous document produced to the Court.

73 Although I accept Clarke undertook confined space testing more than 20 times over a period of 25 years, he was one only of some eight or so personnel who conducted such testing at the relevant date.

74 It is also likely work practices changed and evolved over the period Clarke undertook this task at the smelter. Indeed, the work in question is now undertaken by Alcoa employees.

75 When all these factors are put together, firstly I do not accept that it is likely Silcar employees opened door 1 (or door 2) after confined space testing had been undertaken.

76 Secondly, the probability is either that on this particular occasion testing was not undertaken through door 2 or that, for some reason not brought to Fennell's attention, door 2 was closed after testing. Because the testing procedure was so directly linked to the opening up of the confined space for entry it seems to me that Alcoa must take some responsibility for the access which Fennell was given.

77 The linkage derived from the purpose of the testing undertaken by Alcoa namely, to test the atmosphere within the space when it was ventilated by open doors. It further derived from the practice adopted which required Alcoa personnel (not Silcar personnel) to test the space and approve access. And that practice was reinforced by the confined space permit system.

78 Lastly, Alcoa retained a direct role in supervision of Fennell on the floor of the smelter as he undertook the work in question.

79 As noted above, the work planning form itself designated an Alcoa task leader and back-up Alcoa task leader.

This why we have a - we had a sign-off on an Alcoa task leader and the review process of that form was done in conjunction with the contractor and Alcoa's task leader to ensure that everybody knew between the two groups how it was being done and what was being done.

81 When asked what sort of presence Alcoa had Nash said:

During the work delivery. So when the work packs were handed out Portland Aluminium work delivery, as they were called, would be out on the floor to answer any questions that the guys had, as well as our supervision.

82 In turn, Fennell in fact made an enquiry of an Alcoa supervisor as to how to measure the height of the brushes ie undertake the very task he was performing when he was injured.

83 I accept, as Fennell said, the usual practice was to seek direction and guidance from Alcoa supervisors where necessary. This was supported by the evidence of Dunsmuir, Telfer and Nash.

Portland Aluminium work delivery, as they were called, would be out on the floor to answer any questions that the guys had, as well as our supervision.

85 Derrick Hastings, the Alcoa supervisor to whom Fennell says he spoke, was not called as a witness by Alcoa. It may be accepted that his evidence would not have assisted Alcoa.

86 The employer must take the greater share of responsibility for Mr Fennell's injury because:

• that duty extended to taking account of potential inadvertence of the worker;

• the maintenance contract pursuant to which Silcar undertook work at the smelter devolved ultimate responsibility for the implementation of the work upon Silcar;

• there were a cumulative set of factors which resulted in the breach of Silcar's duty to Mr Fennell, being those I have set out above;

• these factors included a failure to supervise adequately when a direct enquiry by Mr Fennell as to how he should access the brush station safely was made and it must have been apparent to the Silcar supervisor that Mr Fennell was unfamiliar with access to the brush-off station.

87 Nevertheless Alcoa had reserved to itself a supervisory role with respect to the maintenance work in question. In particular, it had reserved the right to formulate the written job instructions, to control access to the confined space and to provide ongoing supervision on the floor of the smelter during the carrying out of the maintenance work.[36]

88 For the reasons I have explained, I accept Alcoa breached its duty to Mr Fennell by failing to provide clear written instructions, failing to properly control access to the confined space and failing to adequately supervise the job over which it retained a direct oversight on the floor of the plant.

89 In the broad it might be said the system of work was Alcoa's and that it retained general control of its implementation and in particular control over access to the confined space. On the other hand, Silcar selected, directly instructed and supervised its personnel and had a non-delegable duty to take reasonable care for their safety.

90 In all the circumstances, I would assess the respective responsibility of the defendants for the plaintiff's injury as being 80 per cent that of Silcar and 20 per cent that of Alcoa.

[3] Mr Dunsmuir worked on the brush station an estimated six to eight times while working for another contractor from 2001 to 2005.

[4] Mr Telfer carried out routine maintenance on the brush station an estimated 20 to 30 times while working for another contractor as a maintenance fitter for 14½ years. In addition, he performed the same task an estimated two or three times while working for Silcar from roughly 2006 to 2009.

[5] Mr Lucas worked with various employers. This included Silcar from approximately 2006 to 2011, during which time he performed the routine maintenance on the brush station 'at least' two to four times.

[6] Mr McIlroy began work at the smelter as a boilermaker with another contractor before taking a position with Silcar as a supervisor in 2006. He ceased working for Silcar in 2009 and was employed by the other contractor again for a period in 2010.

[7] Mr Nash has worked continuously at the smelter since 1996 for various employers. He continues to work there as a supervisor for another contractor.

[8] Mr Clarke remains in that role. He has been employed by Alcoa for 25 years.

[9] See also s 129S of the Accident Compensation Act 1985.

[10] _Wrongs Act 19_58 s 23B(4):

(4) Subject to section 24(2B), a person who in good faith has made or agreed to make any payment in settlement or compromise of a claim made against that person in respect of any damage (including a payment into court which has been accepted) shall be entitled to recover contribution in accordance with this section without regard to whether or not the person who has made or agreed to make the payment is or ever was liable in respect of the damage provided that that person would have been liable assuming that the factual basis of the claim against that person could be established.

[11] See s 24(2) and (2B).

[12] [2005] HCA 14; (2005) 79 ALJR 839.

[13] [1954] HCA 11; (1954) 100 CLR 225, 229; cited with approval by Mason CJ, Toohey and Gaudron JJ in Nicol v Allyacht Spars Pty Ltd [1987] HCA 68; (1987) 163 CLR 611, 617.

[14] [1984] HCA 60; (1984) 155 CLR 306.

[16] [2009] HCA 35; (2009) 240 CLR 1, 11 [20].

[17] [1986] HCA 1; (1986) 160 CLR 16, 47-8 (citation omitted).

[18] Pacific Steel Constructions Pty Ltd v Barahona [2009] NSWCA 406, [122]; Waco Kwikform Limited v Perigo & Workers Compensation Nominal Insurer [2014] NSWCA 140, [48].

[36] Cf Waco Kwikform Limited v Perigo & Workers Compensation Nominal Insurer [2014] NSWCA 140.