Appeal against a decision of the Commission in matter no. OSHT 3/2017 given on 26 April 2018

WESTERN AUSTRALIAN INDUSTRIAL RELATIONS COMMISSION

FULL BENCH

CITATION : 2019 WAIRC 00011

DELIVERED : Wednesday, 16 january 2019

FILE NO. : FBA 4 OF 2018

Appellant

AND

Andrew Chaplyn

State Mining Engineer

Department of Mines and Petroleum

Respondent

ON APPEAL FROM:

Jurisdiction : Occupational Safety and Health Tribunal

Coram : Senior Commissioner S J Kenner

Citation : [2018] WAIRC 00269; (2018) 98 WAIG 392

File No : OSHT 3 of 2017

CatchWords : Industrial Law (WA) - Occupational Safety and Health Tribunal - Appeal against decision by Tribunal of Review of State mining engineer's decision to affirm prohibition notice - Whether in fact a prohibition notice required the removal of hazard or likely hazard and imposed requirements to be complied with until hazard or likely hazard removed - Whether prohibition notice ambiguous and sufficiently clear in its terms - Whether within power to impose a requirement to refrain from permitting any person to be in a place in a mine where they 'might' be exposed (to a hazard)

Legislation : Industrial Relations Act 1979 (WA), s 49

Mines Safety and Inspection Act 1994 (WA), s 3(1)(a), s 3(1)(b), s 3(1)(c), s 31AB, s 31AB(a), s 31AB(b), s 31AB(b)(ii), s 31AC, s 31AC(2), s 31AC(2)(a), s 31AC(2)(b), s 31AD, s 31AD(1), s 31AD(2), s 31AD(2)(a), s 31AD(2)(b), s 31AE, s 31AE(a), s 31AE(b), s 31AE(c), s 31AE(e), s 31AE(f), s 31AF, s 31AF(c) s 31AG, s 31AY, s 31AZ, s 31BA, s 31BB, s 31BB(2)(a), s 31BB(2)(b), s 31DE

Occupational Safety and Health Act 1984 (WA) s 51I

Occupational Health and Safety Act 2004 (Vic) s 112(b)

Mines Safety and Inspection Regulations 1995 (WA) reg 7.28, reg 9.32

Result : Appeal upheld, decision of Tribunal varied, prohibition notice cancelled

Representation:

Counsel:

Appellant : Mr S Vandongen SC and with him Ms E Chamizo

Respondent : Ms T Hollaway

Solicitors:

Appellant : Ashurst Australia

Case(s) referred to in reasons:

Bio-Organics Pty Ltd v The Chief Executive Officer, Department of Water and Environment Regulation [2018] WASC 236

Boughey v R (1986) 161 CLR 10; (1986) 65 ALR 609

F v National Crime Authority (1998) 154 ALR 471

Gray Bruni Constructions Pty Ltd v Victorian WorkCover Authority [2006] VCAT 1969; (2006) 25 VAR 11

Rank Film Distributors Ltd v Video Information Centre [1982] AC 380

Re Lawrence; Ex parte Goldbar Holdings Pty Ltd (1994) 11 WAR 549

Wormald Security Australia Pty Ltd v Rohan (1994) 74 WAIG 2

Reasons for Decision

SMITH AP AND SCOTT CC:

The appeal

1         The appeal has been instituted under s 51I of the Occupational Safety and Health Act 1984 (WA) (OSH Act) and s 49 of the Industrial Relations Act 1979 (WA) (IR Act).

2         The appeal is against an order made by Kenner SC sitting as the Occupational Safety and Health Tribunal (Tribunal) on 26 April 2018 to modify a prohibition notice issued to the appellant which prohibited persons from being in places within the appellant's refinery at Pinjarra where they might be exposed to asbestos.

Background - The extent of use of asbestos at the Pinjarra refinery

3         The appellant mines bauxite and refines aluminium in Australia.  It operates three refineries in Western Australia.  One at Pinjarra, one at Kwinana and one at Wagerup.  The Pinjarra refinery is situated on a large site approximately 10 kilometres from the town of Pinjarra and employs approximately 1,030 employees and contractors.  It was commissioned in 1972 and is one of the largest bauxite refineries in the world, occupying a site of some 6,500 hectares.

4         At the time the refinery was constructed, asbestos-containing materials were not prohibited from use in industry and asbestos was widely used in the construction of the appellant's refinery at Pinjarra.

5         Consequently, materials containing asbestos are present throughout the Pinjarra refinery in the form of protective coatings, claddings, floor tiles, sheeting, asphalt wrapping, different types of lagging and insulation, electrical switchboards and gaskets.  Also, throughout the refinery are paint-type protective coatings (including Coro-Kote) that contain asbestos material.  These coatings are on structures such as girders, beams, handrails and other structures.

6         The appellant keeps an asbestos register as required by the National Code of Practice for the Management and Control of Asbestos in Workplaces (NOHSC: 2018 (2005)).  The register contains a record of:

(a)          all identified asbestos-containing materials on the refinery site; and

(b)          the location of the asbestos-containing material, how much is present, what it is, the condition of the asbestos-containing material and when it was last inspected and surveyed.  A survey is conducted on a three-year cycle by the refinery's dedicated removalist, Cape Onshore Pty Ltd (Cape Australia), which has an office at the refinery.

7         The asbestos register is available to read online to all Alcoa employees at the refinery, but not to contractors unless they are at a supervisor or higher level.

8         The appellant has a program in place at the refinery for asbestos remediation and removal.  Whether asbestos-containing material is removed or remediated depends on the level of risk the material poses and the practicality of its removal, as opposed to its remediation.

9         The appellant has a strategic asbestos management plan which details the company's plan for the safe removal of asbestos on the refinery site.  The appellant also has its own suite of policies and procedures in relation to managing and working with asbestos at the refinery site.  Part of the management of asbestos at the refinery involves the training of employees and contractors by an 'asbestos awareness' program, which covers a range of topics including the nature and risks of asbestos; personal protective equipment; who can lawfully remove/remediate asbestos and what to do if asbestos is discovered on the site.

10      The body with day to day management of asbestos at the refinery is the Asbestos Sub‑Committee.  One of the members of the sub-committee is Mr Andrew Obal, the refinery's health and safety manager.  There are other representatives of the appellant on the sub‑committee, together with a representative of Cape Australia and two employee representatives from the two main unions on the site.  The committee meets regularly to generally discuss asbestos-containing material incidents on the refinery site, update the various registers, discuss the progress of remediation or removal works and discuss planning and budgetary issues.

Asbestos-containing materials at the refinery - how they become a hazard

11      The Tribunal heard evidence from Dr Glossop, an expert called by the State mining engineer.  Dr Glossop is highly qualified in the management and control of asbestos hazards in workplaces.

12      It is common ground there is no safe level of exposure to respirable asbestos fibres. 

13      Dr Glossop testified that the principal diseases caused by asbestos are caused by respirable asbestos fibres that are inhaled deep into a person's lungs.  A respirable asbestos fibre, which is the most dangerous form of asbestos, has a diameter of less than 3µm, a length greater than 5 µm, and a length to width aspect ratio of greater than 3:1.

14      Dr Glossop's evidence was that:

(a)          respiratory diseases mesothelioma and asbestosis are caused by asbestos fibres lodged in a person's lungs;

(b)          amphibole asbestos (crocidolite, amosite, actinolite, tremolite and anthophyllite) have much greater potential to cause all of the asbestos diseases (as amphibole remains in the lung) than serpentine asbestos (chrysotile) (as serpentine asbestos can be dissolved in the lung over time as short as a year);

(c) the level of hazard that arises from asbestos is directly related to the extent to which airborne respirable asbestos fibres occur;

(d) there are two broad categories of asbestos‑containing materials:

(i) friable asbestos-containing materials are those which are asbestos fibres or fibrils that can be broken up and crushed by hand.  Examples of this type of asbestos is lagging insulation, some kinds of insulation board and sprayed limpet asbestos used for fire rating purposes;

(ii) non-friable asbestos is asbestos that is normally contained in something else such as asbestos cement, adhesives, embedded in gaskets and vinyl floor tiles.  The hazard level of non-friable asbestos is generally low, except in cases where the material is subject to aggressive treatment such as cutting or grinding with power tools, or drilling holes through products containing asbestos;

(e) because of the different hazards involved, friable asbestos may only be removed by an unrestricted licensed removalist.  Non-friable asbestos can be removed by a person who has a restricted licence to remove;

(f) friable asbestos-containing materials which acts as a binder to the asbestos may deteriorate over time resulting from heat, moisture, vibration and other chemicals, which makes the material more fragile and increases the risk of release of a larger number of asbestos fibres when the material is disturbed.  This includes the deterioration of protective coatings resulting from sunlight, which exposes the friable asbestos under the coating;

(g) research statistics reveal that the highest incident rate of mesothelioma occurred between 2010 and 2012 amongst trades people;

(h) tradespeople undertaking maintenance work on plant and equipment that involves asbestos-containing material are exposed to respirable asbestos fibres through the disturbance of the material.  The level of exposure is much higher in the case of friable asbestos-containing materials than non-friable asbestos-containing materials; and

(i) non-friable asbestos-containing materials can deteriorate over time.  For example, asbestos cement sheets used in roofing can be worn away by acid rain, frost and lichen which can leave bare asbestos fibres protruding from the sheeting by up to three to four millimetres.  On occasions, fibres can break away completely from the sheeting.

15      Most of the asbestos-containing material at the Pinjarra refinery is non-friable.  What remains of the friable material has either been or is planned to be contained by being encased in a metal wrap or other type of containment, in accordance with accepted and approved practices.

The risks created by maintenance work at the Pinjarra refinery

16      The appellant called Mr Obal to give evidence before the Tribunal about the steps to manage risks in relation to asbestos-containing materials where maintenance, repair and cleaning work is undertaken at the refinery.  Mr Obal testified that for:

(a) work planned in advance, asbestos-containing material is identified in the work to be performed and is arranged so as to minimise the risk of exposure to hazards;

(b) unplanned work, a job safety analysis is required, which will identify the hazards associated with the performance of the work, including asbestos-containing materials or suspected asbestos-containing materials; and

(c) work involving contractors, a different process applies.  The contractor concerned and an employee employed by the appellant must both sign an authority to proceed form which requires each to identify on the form whether any asbestos-containing material may be encountered on the work in question.  If so, they are required to review the asbestos register to confirm whether any asbestos-containing material will be present and, if so, to take steps to control the risk.  This may involve engaging Cape Australia to remediate or remove the asbestos‑containing material, as the case requires.  Once these steps have been undertaken, and the work is to proceed, it is undertaken with the oversight by contractor supervision, not the appellant.

Relevant circumstances which led to the issue of the prohibition notice

17      Inspector Cullen is a Senior Investigator with the Department of Mines, Industry Regulation and Safety.  Inspector Cullen holds a Bachelor of Science in Environmental Health, a Postgraduate Diploma in Occupational Health and Safety, and a Masters in Business Administration, in addition to other health and safety qualifications.

18      In 2014, Inspector Cullen was responsible for occupational health and safety regulation of complex processing plant, which included the appellant's three alumina refineries.  In October 2014, an incident occurred at the Pinjarra refinery involving black pipe lagging that was said to contain asbestos material.  The pipe lagging was attached to a very extensive network of piping and was directly adjacent to work being undertaken by a contractor to the appellant, Transfield Services (Australia) Pty Ltd, and a sub-contractor.  The work that was being carried out was for a replacement of a biological oxalate destruction line (BOD line).  It was alleged that up to 12 people may have been exposed to friable asbestos in a degraded condition. 

19      A prohibition notice was issued on 21 October 2014, stopping the work on the BOD line project.  The notice was lifted on 14 November 2014 after an inspector was satisfied that the work could safely proceed.  Improvement notices were also issued in relation to these works.  Inspectors from the Mines Inspectorate then conducted an investigation as a result of complaints that some employees had been exposed to asbestos.  Following the incident, remedial steps were taken by the appellant that included recladding the entire BOD line, not just the affected area.  This was a serious incident.  Degraded and broken pipe lagging exposing asbestos insulation, some of it in friable condition, close to employees of the appellant and contractors, resulted in a serious risk of exposure to respirable asbestos fibres over a lengthy period.

20      Not long after the BOD line incident, on 19 December 2014, Inspector Cullen investigated a further incident of potential exposure to respirable asbestos fibres at the Pinjarra refinery.  This resulted from an incident report, initiated from the appellant, and concerned the work of another employee of Transfield.

21      Between 16 September 2014 and 24 November 2014, the employee of Transfield engaged in oxy‑acetylene gas cutting work of steel walkway platforms, coated in Coro-Kote, an asbestos‑containing material, in Building 45 at the refinery.  As a result of an investigation into this incident, corrective actions were recommended in the investigation report in relation to contractor management.

22      Sometime later, in about September 2015, Inspector Cullen obtained a copy of the injury-free events log for the Pinjarra refinery.  The log covered the period from July to November 2014.  During this period, some 21 asbestos related events were listed.  Most events were recorded as events of a 'marginal' degree of severity, but one was recorded as a 'critical event'.  However, none of the incidents were reportable asbestos-containing material events that the appellant was required to report to the Mines Inspectorate.  Many of these entries were based on self‑reporting by individuals of what they believed or suspected to be asbestos-containing materials and did not necessarily reflect the presence of asbestos-containing materials as a matter of fact.

23      A further incident arose in July 2016.  Inspector Cullen received a report from the appellant that an incident had occurred at the substation 1, concerning the removal of old switchgear equipment.  Switchgear work had been undertaken by a contractor, UGL Operations and Maintenance Pty Ltd.  An employee of the appellant subsequently reported seeing broken pieces of fibre board material on the floor of substation 1 on 16 July 2016.  It was suspected that the broken pieces of fibre board were asbestos-containing material.  The suspicion was that the fibre board had broken off decommissioned electrical switch gear that had been stored in the substation.  The switchgear fibre board contained both chrysotile and amosite asbestos in a non-friable form.

24      The switchgear substation 1 incident again highlighted problems with contractor management, supervision and control in relation to the identification and safe management of asbestos-containing materials at the Pinjarra refinery, despite changes being made to work practices following the Coro-Kote incident.

25      Two further matters came to Inspector Cullen's attention in late 2016 and early 2017.

26      In late 2016, he received a complaint relating to work performed by an employee of a contractor using a high-pressure water jetting inside a vessel that Cape Australia had previously identified as potentially containing asbestos-containing material.  However, subsequent samples obtained from inside the vessel revealed there were no asbestos fibres present.

27      A second incident was reported to Inspector Cullen by Mr Obal on 3 February 2017.  On 2 February 2017, a contractor had cut the underside of a steel stiffener, which was known to possibly contain an asbestos‑containing material, Gilsomatic.  The asbestos-containing material had not been identified by the appellant before the work had commenced and was only discovered after the job had been completed.  In this instance, the contractor employee had been wearing a respirator.  Once the material was identified, Cape Australia removed the asbestos-containing material.  However, it was discovered that there had been overspray of the asbestos-containing material under the stiffener that had not been earlier identified which led to the incident.

28      From his review of the asbestos register, Inspector Cullen calculated that by area, there was approximately 42,794 square metres of asbestos-containing materials present on the refinery site.

29      From these incidents and a review of the appellant's asbestos register and from his own knowledge of the risks asbestos may pose from workplace exposure, Inspector Cullen formed the opinion that there was asbestos at the Pinjarra refinery that was dangerous, or likely to become dangerous, because:

(a) activities at the refinery, including but not limited to construction work, electrical maintenance and installation work, shutdown and general plant maintenance, refurbishment or replacement of parts and equipment, were likely to result in the disturbance or abrasion of asbestos;

(b) the appellant regularly engages contractors to do the work described in (a).  Some of the workers engaged in past incidents did not wear personal protective equipment, may never have worked with asbestos, may be unfamiliar with the appellant's procedures and were not aware of asbestos hazards;

(c) appropriate identification of the asbestos hazard, adequate risk assessments and suitable control measures were not in place (during incidents);

(d) the appellant is in control of its contractors, its procedures and the asbestos register;

(e) Cape Australia personnel were not present when contractors disturbed asbestos in the incidents he was aware of; and

(f) the injury free events log showed regular asbestos incidents over a significant period, in some cases being at least one event every few weeks.

30      As a result of forming this opinion, Inspector Cullen issued prohibition notice NP‑372‑223057 on 10 February 2017.

31      The terms of prohibition notice NP‑372‑223057 on its face recorded that on 21 October 2014, Inspector Cullen had formed the opinion under s 31AB of the Mines Safety and Inspection Act 1994 (WA) (MSI Act) that the appellant had contravened reg 7.28 of the Mines Safety and Inspection Regulations 1995 (WA) (MSI Regulations) in circumstances that make it likely that the contravention will continue or be repeated and the above matter or activity occasioning the contravention (hazardous materials containing materials at the mine) (the Pinjarra refinery)) constitutes or is likely to constitute a hazard to any person. 

32      The grounds of Inspector Cullen's opinion stated in prohibition notice NP‑372‑223057 were:

As a result of information obtained through investigations performed at the Mine, I am of the opinion that:

1. you have not taken all practicable steps to ensure that persons at the Mine have not been exposed to asbestos at the Mine, in circumstances that indicate that such exposure will continue or be repeated; and

2. further, and in any event, asbestos at the Mine is likely to become dangerous so as to constitute a hazard to persons working there.  In particular:

(a) Between July and October 2014, employees of Transfield Services (Australia) Pty Ltd and PASE Services Pty Ltd were exposed to damaged and/or degraded asbestos containing material at the Mine.

(b) Between 7 July and 16 July 2016 employees of United Group Limited employees were exposed to damaged asbestos containing material at the mine.

Exposure of any persons to damaged and/or degraded asbestos containing materials is likely to result in the inhalation of airborne respirable asbestos fibres leading to their risk of asbestos related diseases.

In accordance with section 31AC(2)(a) and/or section 31AD(2)(a), I require you to remedy the activity or matter.

33      The terms of the prohibition stated in NP‑372‑223057 were as follows:

To the Principal Employer/Manager, under section 31AE of the Act I require that the following prohibition(s) on mining operations be imposed

Pursuant to sections 31AC, 31AD and 31AE of the Act, I require you to remedy the matters referred to above by:

From the date of issue of this notice you are to refrain from permitting any person to be at any place within the Mine where they might be exposed to any asbestos that is being disturbed, abraded or otherwise contacted in any manner, except as follows:

1. Where less than 10 square metres of non-friable asbestos containing materials is removed by persons who have been verified as competent; or

2. Where non-friable asbestos containing materials are removed by licensed asbestos removalists; or

3. Where friable asbestos containing materials are removed by unrestricted licensed asbestos removalists; or

4. Where a sample of any asbestos containing material is removed by a competent expert for the purposes of testing;

5. By express exemption of the State Mining Engineer; or

6. Where, despite all practicable measures having been taken to ascertain whether asbestos was present at a particular place, the presence of asbestos at that place could not reasonably have been ascertained.

Review of probation notice NP‑372‑223057 by the State mining engineer

34      After the issue of prohibition notice NP‑372‑223057, the appellant made an application for a review of the prohibition notice to the State mining engineer.  The State mining engineer held a review and found that Inspector Cullen could not rely on a contravention of reg 7.28 of the MSI Regulations and, therefore, his opinion in this regard was insufficient to invoke s 31AB(a) of the MSI Act.

35      The State mining engineer, however, concluded that there were reasonable grounds for Inspector Cullen to issue prohibition notice NP‑372‑223057 pursuant to s 31AD(2)(b) and s 31AE of the MSI Act.  The State mining engineer held:

(a)          Inspector Cullen accurately stated the ground for his opinion that asbestos which is damaged and/or degraded is likely to result in the inhalation of airborne respirable asbestos fibres, leading to disease;

(b)          for the purposes of s 31AD(2)(a), the removal of the relevant hazard was achieved by keeping persons at a safe distance from respirable asbestos fibres release from asbestos-containing materials; and

(c)          there is no need in every case (where a prohibition notice is issued) for an immediate hazard to exist.  Section 31AB(b) contemplates there may be a situation justifying the issuance of a prohibition notice when a future potential hazard arises.

Relevant provisions of the legislative scheme – prohibition notices

36      Section 31AB of the MSI Act specifies the pre-conditions for the issue of a prohibition notice.  These are, an inspector must form an opinion either that:

(a) a contravention of any provision of this Act –

(i) is occurring at a mine; or

(ii) has occurred at a mine in circumstances that make it likely that the contravention will continue or be repeated,

and any matter or activity occasioning the contravention constitutes or is likely to constitute a hazard to any person; or

(b) a mine, or any plant, mining practice or hazardous substance at or related to a mine –

(i) is dangerous; or

(ii) is likely to become dangerous,

so as to constitute a hazard to any person.

37      In this appeal, the respondent relies upon the pre-conditions in s 31AB(b) as the threshold for issuing prohibition notice NP‑372‑223057.  Consequently, any opinion by Inspector Cullen formed pursuant to s 31AB(a) is irrelevant to the disposition of the matters raised in this appeal.

38      Section 31AC prescribes, among other matters, the content and directions that must be given in a prohibition notice issued on grounds prescribed in s 31AB(a) (due to a breach of the MSI Act).

39      Section 31AD(1) prescribes the formalities as to whom a prohibition notice is to be issued to when an inspector forms the opinion prescribed in s 31AB(b). 

40      It is common ground that the appellant is a person to whom prohibition notice NP‑372‑223057 could be issued.

41      Section 31AD(2) prescribes the requirements to which a prohibition notice must conform.  Section 31AD(2) provides:

The notice is to –

(a) require the person referred to in subsection (1)(a) to remove the hazard or likely hazard; and

(b) in accordance with section 31AE, impose requirements to be complied with by the principal employer or the manager until an inspector is satisfied that the hazard or likely hazard has been removed.

42      The requirements (referred to in s 31AD(2)(b)) to be complied with until the principal employer or an inspector is satisfied that the hazard or likely hazard has been removed are prescribed in s 31AE as follows:

In exercise of the powers conferred by sections 31AC(2)(b) and 31AD(2)(b) an inspector may require the principal employer or the manager –

(a) to stop work at the mine or any specified part of the mine; or

(b) to refrain from doing any specified thing at or in relation to the mine; or

(c) to remove all persons from the mine or any specified part of the mine; or

(d) to take any combination of steps under paragraphs (a), (b) and (c),

except to the extent that provision is made in the prohibition notice either with or without conditions or restrictions for –

(e) any specified work, practice or activity to be carried out or any specified thing to be done at the mine; or

(f) any person to be at the mine or the part concerned.

43      Section 31AF prescribes the formalities of a prohibition notice as follows:

A prohibition notice under this Subdivision must –

(a) state the opinion of the inspector in terms of section 31AB(a) or (b), as the case may require; and

(b) state reasonable grounds for that opinion; and

(c) specify –

(i) where section 31AB(a) applies, the provision of this Act; or

(ii) where section 31AB(b) applies, the mine, or the plant, mining practice or hazardous substance,

in respect of which that opinion is held; and

(d) contain a brief summary of the right to have the notice reviewed under Subdivision 7.

44      A failure to comply with a prohibition notice constitutes an offence (s 31AG).

The decision of the Tribunal on review

45      After considering the expert evidence given by Dr Glossop, the extent of asbestos-containing materials and systems of management of asbestos-containing materials at the Pinjarra refinery, together with facts relied upon to issue probation notice NP‑372‑223057, Kenner SC (sitting as the Tribunal) stated that there were four issues that required determination.  These were:

(a) How should the relevant provisions of the MSI Act regarding the issuance of prohibition notices be interpreted?

(b) Whether, in the context of (a), the opinion formed by Inspector Cullen that asbestos-containing materials at the refinery are dangerous or likely to become dangerous, so as to constitute a hazard to any person, was based on reasonable grounds on the evidence?

(c) Whether the prohibition notice otherwise complied with the requirements of the MSI Act?

(d) Subject to (a) to (c), whether the prohibition notice was adequately framed and if not, should it be modified and if so how?

46      The Senior Commissioner made the following findings which are relevant to the issues raised in this appeal:

(a) The terms of s 31AD(2) of the MSI Act require a prohibition notice to satisfy both subparagraphs (a) and (b).  That is, a notice issued by an inspector must first require the removal of the relevant hazard or likely hazard.  Second, the notice must impose such of the requirements of s 31AE as may be relevant to the circumstances of the case.

(b) As a matter of construction, the language of s 31AD(2) where it is specified that the notice 'is to', imposes an obligation on an inspector to take the steps in s 31AE to address the particular hazard to which the notice relates.  This provision is not discretionary, it is mandatory.

(c) The composite phrase 'is likely to become dangerous' in s 31AB(b)(ii) should be construed by applying the reasoning in Boughey v R (1986) 65 ALR 609 to be taken to mean 'a substantial or real and not remote chance that a hazardous substance will become fraught with danger, or risk, be perilous, hazardous or unsafe'.

(d) From the terms of s 31AB, the pre-condition to the exercise of the power to issue a prohibition notice is the formation of the required opinion, reasonably based.  If an inspector has formed such an opinion, on reasonable grounds, then, under s 31AC and s 31AB, the inspector may, but is not required to, issue a prohibition notice.  If a prohibition notice is to be issued, there are requirements that it must meet, as set out in s 31AF.

(e) The purpose of a prohibition notice is in substance directed towards the removing of a relevant hazard or a likely hazard in the workplace.  When viewed in this light, and given a broad and flexible operation, s 31AD(2)(a) and (b), when read with s 31AE, support the terms of a prohibition notice that directs an employer to ensure that persons are removed from an area of a workplace to remove the risk of exposure to a hazard (in this case, asbestos; specifically, the emission of respirable asbestos fibres from asbestos‑containing materials).  This constitutes the relevant 'removal of the hazard or likely hazard' of which s 31AD(2)(a) speaks.  To achieve this objective, one or a combination of the measures in s 31AE(a) to (c) may be required to be imposed.

(f) There is nothing in the language of s 31AD or s 31AE, when construed broadly, that suggests a time limit applies.  It may well be, as the State mining engineer accepted in argument, that prohibition notice NP‑372‑223057 stays in place until all asbestos is removed from the refinery.  This does not detract from the main purpose and effect of these provisions which is to enable a prohibition notice, as an enforcement measure, to be deployed to eliminate the risk of exposure to a likely hazard.

(g) If the appellant's view of the need for the physical removal of a hazard, that being one that is essentially the removal of a transient but tangible object or substance, were to prevail, some major hazards in the mining industry may not be able to be adequately addressed (such as the removal of water from an underground mine).  A control measure and the legitimate use of a prohibition notice, is the removal of employees or other persons from the areas of the mine from the highest risk of exposure to these hazards.

(h) The use of the word 'might' in the prohibition notice is neither inappropriate nor inconsistent with the statutory scheme.  'Might' means no more than and is conformable with the notion that there is something more than a mere possibility of an occurrence, in terms of a real or substantial chance.  There is little difference in meaning between 'may' and 'might' in this context.

(i) There is nothing in the relevant provisions of the statute that require that any risk be imminent.  The language of s 31AB(b) is the 'likelihood', in terms of it being more probable than not, of a substance becoming a hazard.

(j) Prohibition notice NP‑372‑223057 is not vague and ambiguous.  It contains a clear statement of the hazard and the opinion Inspector Cullen formed.  The statement in the grounds, as to the consequences of exposure to damaged and degraded asbestos, is an accurate representation of the known risk of asbestos fibres likely being released in those circumstances.  Prohibition notice NP‑372‑223057 clearly states the requirement that persons not be at any place at the mine where they might, because of the prohibited activity, be exposed to asbestos.  There are then specified the exceptions from the prohibition that can be categorised into safe removal of asbestos by qualified persons, testing for the presence of asbestos, where the presence of asbestos could not reasonably be anticipated and providing for an exemption on the basis that the State mining engineer is satisfied any asbestos-containing material is not hazardous.

47      Senior Commissioner Kenner then turned to the question whether prohibition notice NP‑372‑223057 was adequately framed.  The Senior Commissioner found the contention made by the appellant that (on Dr Glossop's evidence) mere 'contact' with asbestos cannot pose a hazard, should be accepted, as it is damage, deterioration and disturbance that can render asbestos hazardous.  Accordingly, Kenner SC found that the reference to 'contact' in prohibition notice NP‑372‑223057 should be removed and the prohibition notice should be modified accordingly.  Senior Commissioner Kenner also found that the reference in exception 4 to 'competent expert' should be modified to 'competent person', to be consistent with the meaning of that term in the 'Code'.

48      Consequently, the effect of the decision of the Tribunal was to modify prohibition notice NP‑372‑223057 as follows:

From the date of issue of this notice you are to refrain from permitting any person to be at any place within the Mine where they might be exposed to any asbestos that is being disturbed, abraded or otherwise contacted in any manner that is or has been damaged and/or disturbed and/or has deteriorated in any manner, except as follows:

1. Where less than 10 square metres of non-friable asbestos containing materials is removed by persons who have been verified as competent; or

2. Where non-friable asbestos containing materials are removed by licensed asbestos removalists; or

3. Where friable asbestos containing materials are removed by unrestricted licensed asbestos removalists; or

4. Where a sample of any asbestos containing material is removed by a competent expert competent person for the purposes of testing;

5. By express exemption of the State Mining Engineer; or

6. Where, despite all practicable measures having been taken to ascertain whether asbestos was present at a particular place, the presence of asbestos at that place could not reasonably have been ascertained.

(See the order made by the Tribunal:  [2018] WAIRC 00269; (2018) 98 WAIG 392).

Appellant's amended grounds of appeal

49      The point made in ground 1 of the appeal is the appellant contends that the Tribunal erred in affirming prohibition notice NP‑372‑223057, as the prohibition notice was invalid as it failed to comply with s 31AD(2)(a) and (b) of the MSI Act, in that it:

(a) did not require the appellant to remove any hazard or likely hazard specified in the prohibition notice;

(b) did not impose on the appellant any requirement to be complied with until an inspector was satisfied that the hazard or likely hazard specified in the prohibition notice had been removed; and

(c) is by reason of (b) specified to endure indefinitely and/or imposes a permanent restriction on the appellant and, as such, is beyond power.

50      If the appellant is successful in ground 1 of the appeal, its remaining grounds of appeal fall necessarily away.

51      In ground 2, the appellant contends that the Tribunal erred in finding that prohibition notice NP‑372‑223057 was not vague and ambiguous.  It says the prohibition notice failed to specify unambiguously and with sufficient clarity, the matters required to be specified in a prohibition notice by operation of s 31AE(a), (b) and (c).

52      In grounds 3 and 5, the appellant contends that prohibition notice NP‑372‑223057, in so far as it is expressed to apply when persons 'might' be exposed to asbestos-containing material, offends s 31AB(b) because the use of the word 'might' implies that the prohibition notice was not grounded in either an opinion or conclusion that asbestos-containing material is either dangerous, or likely to become dangerous, so as to constitute a hazard to any person.

53      In appeal grounds 4 and 6, the appellant asserts that the modification of prohibition notice NP‑372‑223057, by including a reference to possible exposure to asbestos that has 'deteriorated in any manner', fundamentally altered the ambit and reach of the prohibition notice without providing substantive reasons as to why that modification was in the circumstances appropriate.

54      In ground 7, the appellant asserts that the Tribunal denied it procedural fairness by failing to afford it the opportunity of being heard in relation to the modification made to prohibition notice NP‑372‑223057 in circumstances where the modifications significantly and fundamentally altered the nature and extend of the appellant's obligations with respect to the prohibition notice.

Did the Tribunal err in finding that prohibition notice NP‑372‑223057 complied with the requirements of the MSI Act?

(a) Ground 1 of the appeal

55      As the respondent points out in this matter, the jurisdictional threshold to issue a probation notice pursuant to the power conferred to do so in s 31AB(b) of the MSI Act, was whether or not asbestos‑containing materials at the Pinjarra refinery constitute a hazardous substance, or a likely hazard, that may result in harm to the health of a person.

56      It is apparent from Kenner SC's reasons for decision, and from the express terms of prohibition notice NP‑372‑223057, that Inspector Cullen had formed an opinion under s 31AB(b) that a hazardous substance at the mine (specifically asbestos) is likely to become dangerous so as to constitute a hazard to persons working there. 

57      It is clear that Inspector Cullen formed the view that the 'hazard or likely hazard' was the emission of respirable fibres from damaged, disturbed or deteriorated asbestos‑containing materials and Kenner SC concurred [101].

58      Having decided that Inspector Cullen had properly formed that opinion, the Tribunal was then required to consider whether the prohibition notice conformed with s 31AD(2).

59      Senior Commissioner Kenner correctly found that a notice issued by an inspector under s 31AB(b) must impose steps on a person that must be complied with.  These are, a notice must (by operation of s 31AD(2)) first require the removal of the relevant hazard or likely hazard, and second impose such of the requirements of s 31AE as may be relevant to the circumstances of the case [88] - [89].

60      The Senior Commissioner appeared to have accepted that a prohibition notice must state the matters specified in s 31AF.

61      The Senior Commissioner properly accepted that a hazard arises from asbestos if asbestos‑containing materials have deteriorated or have been disturbed, which gives rise to the likelihood of airborne asbestos fibres being released into the air [107].

62      The respondent argues Kenner SC correctly found that the removal of the hazard was (as contemplated by s 31AD(2)(a)) to occur by the removal of persons from locations where the asbestos is likely to become dangerous; that is, removal from areas where asbestos is being damaged and/or disturbed and/or has deteriorated in any manner.  Thus, it is said by removing persons from these areas, that the hazard is removed as the hazard is the exposure of persons to respirable airborne fibres.

63      The respondent says that the prohibition notice permits persons to be in parts of the refinery where there is asbestos (as they are able to do so now) until such time that the asbestos has deteriorated or when it is likely that works will damage or disturb the asbestos which could cause the release of fibres.  In practical terms, it is said that workers are able to work in areas containing asbestos‑containing materials that are in good condition, but says that if there is a potential for work to damage or disturb asbestos‑containing materials, further controls should be in place to ensure no damage occurs to ensure the prohibition notice is not breached.

64      The respondent also says that if it is intended that a worker is to go into an area that contains asbestos‑containing materials that are damaged, disturbed or deteriorated in any manner, then the exceptions to the notice are enlivened and that it must only be one of those persons listed in the exceptions that is to carry out the work to remove the hazard, or likely hazard.  The respondent says, on the evidence, this course of action would be desirable.

65      The difficulty with the contentions put on behalf of the respondent is simply that prohibition notice NP‑372‑223057 does not have this effect.

66      The difficulty with the respondent's arguments are that prohibition notice NP‑372‑223057 does not create the regime the respondent says it does.

67      Prohibition notice NP‑372‑223057 does not put in place a regime to remove the hazard or likely hazard.  A direction to prohibit persons from being in a place in the refinery where they might be exposed to damaged, disturbed or deteriorated asbestos-containing material could be said to be a regime to avoid exposure to a hazard or likely hazard that could be properly characterised as requirements to be complied with within the meaning of s 31AE, but is not a regime authorised by s 31AD(2)(a) and (b).  This is because a regime to avoid is not a regime to remove.  Nor is it a regime that is to be in place until an inspector is satisfied that the hazard or likely hazard has been removed.

68      As the appellant points out, in order to comply with s 31AD(2)(a), prohibition notice NP‑372‑223057 must require the appellant to remove asbestos‑containing materials that are damaged and/or disturbed and/or has deteriorated.

69      However, prohibition notice NP‑372‑223057 does not require the appellant to remove the hazard or likely hazard.  Instead, the prohibition notice requires the appellant to 'refrain from permitting any person to be at any place within the Mine where they might be exposed to any asbestos'.

70      Clearly, a prohibition notice may direct an employer to remove persons from an area of a workplace for the purpose of removing the risk of exposure to a hazard (s 31AE(c)).  However, the terms of prohibition notice NP‑372‑223057, when properly construed, wrongly conflate the removal of the persons from a part of the mine (which can only be a requirement to be complied with until the removal is complete) with the removal of a hazard or likely hazard.

71      The power to impose a requirement to remove persons from the mine or any specified part of the mine can only be authorised pursuant to s 31AD(2)(b) for the period of time that it takes to remove the hazard or likely hazard.  However, where a notice does not require the removal of a hazard or likely hazard, it is not open to impose any of the requirements specified in s 31AE.

72      In the absence of any direction in prohibition notice NP‑372‑223057 to remove the hazard or likely hazard, the requirement to refrain from permitting any person to be at any place within the mine is ongoing and is not imposed for a limited time (for the hazard or likely hazard to be removed).

73      For these reasons, we are satisfied that ground 1 of the appeal is made out.

(b) Ground 2 of the appeal

74      Ground 2 of the appeal asserts that the terms of prohibition notice NP‑372‑223057, as ultimately endorsed and modified by the Tribunal, failed to comply with s 31AE(a), (b) and (c), in that on its face it fails to specify unambiguously and with sufficient clarity the matters specified in the steps or requirements to be taken in those subsections (until the inspector is satisfied the hazard or likely hazard has been removed).

75      We agree that the words used in s 31AD and s 31AE, and the context in which they appear in the MSI Act, confer power to issue a prohibition notice that must be certain in its terms as a condition of its valid exercise. 

76      This intention arises from the stated objects in s 3(1)(a), (b) and (c) of the MSI Act which provide (among other objects):

(a) to promote, and secure the safety and health of persons engaged in mining operations; and

(b) to assist employers and employees to identify and reduce hazards relating to mines, mining operations, work systems and plant at mines; and

(c) to protect employees against the risks associated with mines, mining operations, work systems at mines, and plant and hazardous substances at mines by eliminating those risks, or imposing effective controls in order to minimize them; and

77      This intention also arises from s 31AF and the fact that a person issued with a prohibition notice commits an offence if the person does not comply with the notice, or such of the provisions of the notice as are applicable to the person (s 31AG).

78      The requirement to specify the matters in s 31AF(c) can only be construed in this context as a requirement to unambiguously identify and make these matters clear (see the discussion in a different statutory context in Re Lawrence; Ex parte Goldbar Holdings Pty Ltd (1994) 11 WAR 549, 554, 566 (Malcom CJ); applied by Allanson J in Bio-Organics Pty Ltd v The Chief Executive Officer, Department of Water and Environment Regulation [2018] WASC 236 [31] - [34]).

79      Thus, on its face a prohibition notice issued pursuant to s 31AB(b) (when read with s 31AF(c)) must unambiguously identify and make clear the mine, or the plant, mining practice or hazardous substance (that is dangerous or likely to become dangerous). 

80      When s 31AF is read together with s 31AD and s 31AE, and within its context and legislative purpose, a prohibition notice must unambiguously identify and make clear what is to be done to remove the hazard and the requirements that are to be complied with until the inspector is satisfied the hazard or likely hazard has been removed.

81      Prohibition notice NP‑372‑223057 purports to require persons to refrain from being in specified areas of the Pinjarra refinery, namely those areas where they 'might be exposed to any asbestos that is or has been damaged and/or disturbed and/or has deteriorated in any manner'.

82      As the appellant points out, the part (or parts) of the refinery that are the subject of the requirement are defined by reference to:

(a) whether a person 'might' be exposed to asbestos, without any guidance about what 'might be exposed' means, and what state the asbestos is in;

(b) the condition that the asbestos is in or, at some undefined time in the past, 'has been' in; and

(c) whether the asbestos is or has been damaged and/or disturbed and/or has deteriorated in any manner.

83      We agree the use of the word 'might' in prohibition notice NP‑372‑223057 raises ambiguity, as it raises a concept going to a vague possibility that a person may be exposed to respirable asbestos fibres.  We explain our reasoning in this regard in our reasons that follow, in respect of grounds 3 and 5.

84      We also agree the words 'has been' could also give rise to ambiguity as it is impossible to suggest prohibition notice NP‑372‑223057 itself specifies a part of the mine or a hazardous substance by reference to something that has been, and not what the state of the asbestos-containing material is at the relevant time (that is, the time at which the work by the employees and contractors takes place or is to take place). 

85      Therefore, while the prohibition notice itself does not identify in precise terms the particular asbestos‑containing materials, the state or condition of it or where on the refinery site the material is located, the appellant's own records make this information available to the appellant (subject to the ambiguities regarding the use of 'might' and 'has been').

86      Is this sufficient bearing in mind that the imposition of a prohibition notice places the appellant in jeopardy of prosecution and penalty if it breaches the prohibition notice?

87      In our view, it is not sufficient in that context.  The person in receipt of a prohibition notice is entitled to know, with a high degree of specificity, what it is prohibited from doing.  The lack of specificity may make uncertain the outcome of any prosecution for breach.  This lack of specificity, as well as reliance on the appellant's own records by the respondent for the purposes of being satisfied of compliance with a view to lifting the prohibition notice, or for a prosecution in the case that it alleges a breach, is also problematic (although the latter is not the concern of this appeal).

88      The manner in which the prohibition notice has been written is to, in effect, say to the appellant that it is prohibited from allowing persons to work, without actually specifying the terms of the prohibition and a required rectification.  It leaves it to the appellant to work out what this means and to manage it.  On one hand, this seems to be a perfectly reasonable and sensible approach, particularly as the site is large, the amount of asbestos‑containing materials is significant and the appellant has detailed records.  However, the regime set out in the MSI Act is one of inspection by a regulatory body which has the power to both direct improvement (which it did not do in this case, but which it could have done with a view to achieving the same result) and prohibit activity or access until rectification, with the capacity to prosecute for breach, with penalties.

89      In our view, in such a scheme a prohibition notice ought to specify, in particular what the recipient is prohibited from doing, rather than give a vague direction and require the recipient to work it out for themselves.

90      The prohibition notice in this case did not meet those requirements.

91      The appellant also argues that the words 'damaged and/or disturbed and/or has deteriorated in any manner' are not clear.  It asks the question; does it mean microscopically deteriorated and to what extent exactly does it mean in terms of the appellant being required to identify itself what part of the mine it is required to ensure people are not permitted to go to?

92      However, we do not agree that ambiguity arises in this respect.

93      As counsel for the respondent points out, the appellant has developed an extensive manual to determine whether any of the asbestos‑containing materials in the Pinjarra refinery is degraded or is deteriorating. 

94      The evidence before the Tribunal established that the appellant has a comprehensive knowledge of not only the types of asbestos contained at the Pinjarra refinery but also the location of the asbestos and has a clear system of work in place for identifying and determining whether asbestos‑containing material has degraded or deteriorated in any manner.

95      The appellant's 'Inspection and Risk Evaluation Manual for Materials Containing Hazardous Fibres at Pinjarra Refinery' contains a classification scale of degraded and deteriorating asbestos-containing materials, together with photographs and detailed descriptions for each particular type of asbestos that is located, or has been located, in the Pinjarra refinery (AB 18.57, pp 630 - 693).

96      The respondent also points out that whether asbestos is or has been damaged, disturbed or deteriorated in any manner was explained in evidence by the appellant's witness, Mr Obal, as follows:

(a) The Inspection and Risk Evaluation Manual for Materials Containing Hazardous Fibres at Pinjarra Refinery is a document which provides guidance on making an assessment about the condition of those materials.  The assessment is visual, looking at the level of deterioration and damage.  There are broadly three categories (fair, good and poor) (ts 131).

(b) 'Fair' is something that in the future may become a problem so it warrants monitoring to make sure it does not deteriorate further.  'Poor' is even more deterioration than 'fair'.  'Good' means there is no signs of any deterioration (ts 132).

(c) In the strategic management plan asbestos is referred to as being in fair condition which Mr Obal says is deteriorating condition that has potential to become hazardous.  Where the condition is noted as 'fair' and the action is 'remove' this is because it is deteriorating (ts 134).

(d) The Inspection and Risk Evaluation Manual for Materials Containing Hazardous Fibres and a risk matrix explains and enables classification of some asbestos-containing material in terms of its condition.  Then, based on the potential for exposure, it provides a priority for action (ts 193).

97      In ground 2 of the appeal, the appellant also argues that the particularised exceptions to the direction given in prohibition notice NP‑372‑223057 are not identified, nor made unambiguously clear.  In particular, the appellant contends that it is not clear what 'removed' means or 'removed by persons who have been verified as competent' in point 1 and it is not clear in point 4 who a 'competent person' is for the 'purpose of testing', or what type of 'testing' is being referred to. 

98      We do not agree.

99      These terms and procedures are explained at length in the 'How to Manage and Control Asbestos in the Workplace Code of Practice' (Tab 18.50, pp 439 - 506 (AB)) and the 'Code of Practice for the Safe Removal of Asbestos' (2nd ed) [NOHSC: 2002 (2005)] (Tab 18.51, pp 507 ‑ 593 (AB)).  Both codes are well known to the appellant, its employees and agents who are responsible for the removal and testing of asbestos‑containing material.  In these circumstances, a contention that the exceptions are not specified with sufficient certainty cannot be made out.

100   In addition, reg 9.32 of the MSI Regulations provides:

9.32. Removal of asbestos

Each responsible person at a mine must ensure that if any asbestos removal work is carried out at the mine — 

(a) the work is carried out in accordance with the procedures specified in the 'Code of Practice for the Safe Removal of Asbestos' 2nd Edition [NOHSC:2002 (2005)] declared by the NOHSC and published in April 2005; and

(b) the district inspector is notified in writing before the work commences.

Penalty: See regulation 17.1.

101   Notwithstanding the findings made in [91] - [100], we are satisfied that, in part, ground 2 of the appeal has been made out.

(c) Grounds 3 and 5 of the appeal

102   The appellant's contention in appeal grounds 3 and 5 is that prohibition notice NP‑372‑223057, which is expressed to apply when persons 'might' be exposed to asbestos‑containing materials, offends s 31AB(b), essentially because the word 'might' implies that the prohibition notice was not grounded in either an opinion or conclusion that asbestos‑containing materials are either dangerous, or likely to become dangerous, so as to constitute a hazard to any person.

103   In determining the meaning of 'might' in prohibition notice NP‑372‑223057, Kenner SC was referred (by the appellant's counsel at first instance) to a decision of the Victorian Civil and Administrative Tribunal in Gray Bruni Constructions Pty Ltd v Victorian WorkCover Authority [2006] VCAT 1969; (2006) 25 VAR 11 when it considered an application to review a prohibition notice under s 112(b) of the Occupational Health and Safety Act 2004 (Vic).  Under the Victorian Act, an inspector was empowered to issue a prohibition notice if they believed that 'an activity may occur at a workplace that, if it occurs, will involve an immediate risk to the health or safety of a person'.  In Gray Bruni Constructions, MacNamara ADP found that 'may' in this context means 'something more than mere possibility of occurrence must be made out' [82].

104   Whilst Kenner SC had regard to the decision in Gray Bruni Constructions, the Senior Commissioner made a finding that the legislation under consideration in that matter was materially different to the MSI Act, and thus such comparisons were of limited value.

105   Senior Commissioner Kenner also found that the use of the word 'might' in prohibition notice NP‑372‑223057 was not inappropriate or inconsistent with the MSI Act statutory scheme.  The Senior Commissioner went on to find that the word 'might' meant something more than a mere possibility of an occurrence, in terms of a real or substantial chance and that there was little difference in meaning between 'may' and 'might' in this context.

106   With respect to the Senior Commissioner, we do not agree with this analysis.

107   Section 31AB(b) and s 31AD authorises the issue of the prohibition notice to require the removal of a hazard or likely hazard, not the removal of something that 'might' result in a person being exposed to a hazard or likely hazard, or to remove something that 'might' be a hazard.

108   The word 'might' does not mean the same as 'likely'.  The word 'might' points to a lower threshold than 'likely'.

109   The statutory requirement in s 31AB(b) is not only to identify the hazard in the prohibition notice, but to identify the opinion that is required to be held by the inspector.  In the words of Franklyn J in Wormald Security Australia Pty Ltd v Rohan (1994) 74 WAIG 2, 3:

[T]here must exist some evidence on which to base the opinion and that evidence must go further than to establish only a possibility … the evidence must show that there exists something more than the bare possibility that injury or harm of that nature will occur from the activity in question.

110   The Macquarie Dictionary online defines the word 'might' as the past tense of 'may' and states that when the word 'might' is used as a verb it is a word that can be used to express strong uncertainty, or is used to express tentative suggestions.

111   However, it should be noted in F v National Crime Authority (1998) 154 ALR 471, 481 - 482, O'Loughlin J (in a very different statutory context to the MSI Act) observed that the words 'may' and 'might' are not necessarily interchangeable.  'Might' in some contexts may require a lower level of proof than 'may'.  His Honour relevantly said:

Both 'may' and 'might' are commonly used when referring to a possibility, or an opportunity and in that sense, they do not impose the same degree of capability as 'will' and 'would'.  Something that 'may or might' happen is less likely to occur than something that 'will or would' happen.  But within the field of possibilities 'may' could suggest a possibility that is more likely to occur than one which 'might' only occur.  Applying these dictionary definitions to the various expressions, it appears that there is an ascending order.  An answer that 'might' tend to incriminate is at the lowest level – meaning that the risk of incrimination need only be a low level possibility to entitle a witness to refuse to answer the question.  If however, the test is premised on the statement that the question 'may' tend to incriminate, the risk attendant on the witness having to answer the question could be marginally greater.  But if the witness must answer a question unless the answer 'will' or 'would' tend to incriminate, one is elevated from possibilities – perhaps into the world of probabilities; there would be a far greater compulsion on the witness to answer in those cases where he or she could only be excused where an answer 'will' or 'would' tend to incriminate.

The practical differences that flow from the use of 'may' as distinct from 'might' are, in my opinion, slight.  Indeed, there is a case for suggesting that some use the two words interchangeably.  An example of that proposition appears in Pyneboard Pty Ltd v Trade Practices Commission (1983) 152 CLR 328; 45 ALR 609.  The relevant legislation that was then under consideration contained that phrase 'may tend to incriminate' yet the editor of the headnote to the case incorrectly stated that the statute did not excuse a person from furnishing information 'on the ground that the information or document might tend to incriminate the person…'.  Likewise, in their joint judgment (at CLR 337), Mason ACJ, Wilson and Dawson JJ, in the course of making a general observation about the construction of the relevant section used the phrase 'might tend to expose the party…'

112   The same interchangeable use of 'may' and 'might' is to be found in the speeches in the House of Lords in Rank Film Distributors Ltd v Video Information Centre [1982] AC 380.

113   Irrespective of whether there is any difference between the words 'may' and 'might', reliance upon the word 'might' in prohibition notice NP‑372‑223057 gives rise to a prohibition against a bare possibility that an exposure to airborne respirable asbestos 'might' occur and an ensuring bare possibility the exposure 'might' give rise to an injury or harm.  Such a prohibition in these terms is simply not sufficient to enliven the power to issue a prohibition notice pursuant to s 31AB.

114   Whilst the evidence before the Tribunal made it absolutely clear that the danger to a person's health from respirable fibres of asbestos cannot be understated, s 31AB(b) requires an inspector to form a requisite opinion that a hazardous substance is dangerous or is likely to become dangerous so as to constitute a hazard to any person, and by the use of the word 'likely' requires a higher degree of probability than conveyed by the word 'might' so as to invoke the power to issue a prohibition notice. 

115   As the appellant points out, it is the imposition of the word 'likely' that ensures that the power to issue a prohibition notice is not enlivened on the strength of remote or hypothetical possibilities. 

116   The accepted meaning of the word 'likely' in Boughey v R (1986) 161 CLR 10 is to convey a notion of substantial chance that is real and not remote, regardless of whether it is less or more than 50 per cent.

117   For these reasons, grounds 3 and 5 are made out.

(d) Grounds 4 and 6 of the appeal

118   For the reasons we have given in respect of ground 2, we do not find it necessary to consider grounds 4 and 6 of the appeal.

(e) Ground 7 of the appeal

119   Turning to ground 7, we do not accept that the Tribunal denied the appellant procedural fairness.  The appellant was squarely provided with the opportunity of making submissions on any proposed amendments or modifications to prohibition notice NP‑372‑223057.  During the course of the hearing, Kenner SC raised the issue of potential modifications with the parties and invited each of them to make submissions as to modifications (ts 103).

120   Senior Commissioner Kenner informed the parties that it would be helpful for him to hear from both parties as to an alternative submission (about what modifications should be made to the notice) in the event that a finding was made (for whatever reason) that the notice should remain in place but be modified. 

121   In response, counsel on behalf of the appellant informed Kenner SC that in the event that the Tribunal was minded to issue a prohibition notice in revised form, that it (first) be put in that form and the parties then be asked to comment on it.  The Senior Commissioner said in response, 'All right.  Well perhaps you can have a think about that but I think it would be helpful to the Tribunal'.

122   The respondent later proposed in a set of reply submissions the modifications were ultimately adopted by the Tribunal.

123   Whilst there was no substantive debate regarding the appropriateness or otherwise of the proposed modifications that were ultimately adopted by the Tribunal, we do not accept the appellant's contention that it was not in a position to make submissions regarding the modifications.  After having received the reply submissions from the respondent, the appellant could have sought an opportunity to make a submission about the proposed modifications (as Kenner SC had indicated to the appellant's that it would be helpful to receive submissions in respect of any proposed modifications) but it failed to do so.

The orders that should be made

124   For these reasons, we are of the opinion that grounds 1, 2, 3 and 5 of the grounds of appeal have been made out.

125   We would make orders to uphold the appeal and vary the decision of the Tribunal by revoking the decision of the State mining engineer.  We would also make an order cancelling prohibition notice NP‑372‑223057.

MATTHEWS C:

126   On 10 February 2017 an inspector of mines appointed under the Mines Safety and Inspection Act 1994 issued the appellant with a prohibition notice under that Act.

127   A prohibition notice may be issued pursuant to section 31AB Mines Safety and Inspection Act 1994 if an inspector is of the opinion that a contravention of the Mines Safety and Inspection Act 1994 is or has occurred and any matter or activity occasioning the contravention constitutes or is likely to constitute a hazard to any person or a mine, plant, mining practice or hazardous substance at a mine is dangerous or likely to become dangerous so as to constitute a hazard to any person.

128   Reading the prohibition notice it seems to have been issued primarily because the inspector was of the opinion that the appellant had contravened a provision of the Mines Safety and Inspection Act 1994 and the circumstances of the contravention were such that the inspector was of the opinion it was likely the contravention would be repeated.

129   Again, from my reading of the prohibition notice, it seems to have been issued because the inspector was of the opinion that employees of contractors engaged to do work at the mine by the appellant had been exposed to damaged or degraded asbestos and that the appellant had not taken all practicable steps to ensure this would not again occur.

130   Section 31AC(2)(b) Mines Safety and Inspection Act 1994 requires a prohibition notice to impose requirements to be complied with by the person in control of the mine until an inspector is satisfied that the problematic matter or activity raised by the prohibition notice has been remedied.

131   The prohibition notice prohibited the appellant from "permitting any person to be at any place within the mine where they might be exposed to any asbestos that is being disturbed, abraded or otherwise contacted in any manner."  The prohibition notice then goes on to set out exceptions to this prohibition as follows:

1. Where less than 10 square metres of non-friable asbestos containing materials is removed by persons who have been verified as competent; or

2. Where non-friable asbestos containing materials are removed by licensed asbestos removalists; or

3. Where friable asbestos containing materials are removed by unrestricted licensed asbestos removalists; or

4. Where a sample of any asbestos containing material is removed by a competent expert for the purposes of testing;

5. By express exemption of the State Mining Engineer; or

6. Where, despite all practicable measures having been taken to ascertain whether asbestos was present at a particular place, the presence of asbestos at that place could not reasonably have been ascertained.

132   It is clear to me that the "exceptions" are an attempt by the inspector to devise a safe system of work for the appellant.  It may be that the exceptions are an attempt to utilise section 31AE(e) and (f) Mines Safety and Inspection Act 1994 but they clearly go beyond this.

133   "Exception 6" is illustrative of my point.  It says, I think, that the prohibition notice will not be breached if "all practicable measures" have been taken to find out if asbestos was at a place before a person was permitted to be at the place.  That is a clear reference to system of work issues and could not be brought with section 31AE(e) or (f) Mines Safety and Inspection Act 1994.

134   I consider that the inspector has, in effect, attempted to devise a standing system of work in the prohibition notice.

135   Although the wording of the prohibition is a bit loose, the object of the prohibition notice, drawing at the moment solely upon the parts I have emphasised, seems to have been to make sure no one went near damaged or degraded asbestos until the appellant had developed practicable steps to ensure that persons at the mine were not exposed to asbestos fibres.

136   Although I skip ahead here to what took place at the appeal, I am reinforced in my view that this is essentially what the matter is about by the written submissions of the respondent at [53] as follows:

In practical terms … if workers are going into an area containing [asbestos] and that [asbestos] is in good condition, they are permitted to work.  If there is the potential for work to damage or disturb this [asbestos], then further controls should be in place to ensure no damage actually occurs and therefore the Prohibition Notice is not breached.  This may occur in a number of ways, such as training, supervision, specific documented processes, and/or restricting certain power tools onsite.  The controls employed may change depending on the type and location of the asbestos and therefore have been left for the Appellant to determine what is appropriate depending on the particular circumstances.

137   I also refer to written submissions of the respondent at [54] that:

If it is intended that a worker is going into an area that contains [asbestos] that is damaged, disturbed or deteriorated in any manner then the exceptions in the Notice are enlivened and it must be one of those persons listed in the exceptions that does the work - a competent person if less than 10sqm; a licensed asbestos removalist (licence requirements depending on type of asbestos - friable or non-friable); or an exemption is applied for to the State Mining Engineer.

138   My interpretation of the above is that the respondent is submitting that the prohibition notice is about ensuring the appellant has a system of work in place to minimise the risk of persons inhaling asbestos fibres.  The respondent says that the appellant may develop its own system of work in one situation (that is where there is a potential for work to damage or disturb asbestos in good condition) but that in relation to another situation (where asbestos is already damaged, disturbed or deteriorated) the appellant must follow the system of work set out in the prohibition notice.

139   The respondent then is, in my view, seeking to have the prohibition notice upheld and continue in force so that he may impose a certain system of work upon the appellant into the indeterminate future deal with a problem identified by one of his inspectors in 2017.

140   In my view, such an approach does not conform with the Mines Safety and Inspection Act 1994.

141   If the circumstance that gives rise to a prohibition notice is a failure to take practicable steps, then the prohibition notice can only invoke the extraordinary powers under section 31AE until such time as that failure is remedied.

142   The remedy is not for the inspector or anyone else to devise and impose a safe system of work upon the person in control of a mine.

143   The statutory responsibility is upon an employer to, so far as is practicable, provide and maintain a working environment in which the employer's employees are not exposed to hazards.

144   While the respondent may stop an activity at a mine where there is danger in the conduct of such an activity, in a case where the activity is dangerous because of an alleged failure on the part of the person in control of the mine to take practicable steps to minimise risks, it is not for the respondent to devise and impose a system of work upon the person in control of a mine to reduce or minimise the risks associated with the activity.  The respondent should stop the activity with the obligation being upon the person in control of the mine to then satisfy the respondent that it has developed and instituted a safe system of work, that is a system of work which, as practicably as possible, minimises the risks.  At that point the prohibition notice would be lifted.

145   It would be, in my view, a dangerous development for the respondent to develop and impose a system of work upon persons in charge of mines in circumstance such as these.

146   In any event, I do not consider the Mines Safety and Inspection Act 1994 allows it.

147   In my view, it is clear that it is the persons in charge of mines who have to remedy matters and not the respondent.  Insofar as the prohibition notice prohibits a certain activity and then goes on to devise and impose a system of work, it is beyond power.

148   I find that [54] of the respondent's submissions reveal the problem with the prohibition notice.  A prohibition notice cannot direct a person in charge in charge of a mine to adopt a certain system of work in a "practicable steps" matter for all time.

149   I should make clear that I do not consider section 31AE(e) or (f) Mines Safety and Inspection Act 1994 allows an inspector to devise a standing or permanent system of work.  Those subsections are intended to be exceptions to prohibitions which will allow the person in charge of a mine to do work or have persons at the mine to remedy the problem at the mine identified in the prohibition notice.

150   The problems in this case emerged, in my view, because the prohibition notice inelegantly and unfortunately tried to invoke, or was found to have invoked, a part of the statutory regime wholly unsuited to dealing with the problem the circumstances giving rise to the prohibition notice revealed.

151   I have set out above that the Mines Safety and Inspection Act 1994 allows a prohibition notice to be issued by an inspector if he is of the opinion there is a hazardous substance at a mine that is dangerous or is likely to become dangerous so as to constitute a hazard to any person.

152   Although the prohibition notice cited a breach of the Mines Safety and Inspection Act 1994 as the ground for its issue, and goes on to specify the provision said to have been breached, it also made some references to a hazardous substance, being "damaged and/or degraded asbestos."

153   Under a subheading headed "Grounds", which is confusing in itself given the heading is also "Grounds", the inspector refers to "asbestos at the Mine [which] is likely to become dangerous" and then explains that "exposure of any persons to damaged and/or degraded asbestos containing materials is likely to result in the inhalation or airborne respirable fibres leading to the risk of asbestos related diseases."

154   There is then reference to "section 31AC(2)(a) and/or section 31AD(2)(a)."

155   I have already set out the "prohibition" section of the prohibition notice.

156   However, the prohibitions and exceptions thereto do not match up with the problem revealed by the circumstances giving rise to the prohibition notice and do not match up with section 31AB(b) Mines Safety and Inspection Act 1994 (the subsection referring to hazardous substances) or to section 31AD(2)(a) (the subparagraph allowing a prohibition notice to require a person in control of a mine to "remove the hazard or likely hazard.")

157   I say this because the prohibitions do not require the "removal of a hazardous substance."  The respondent I think tried to argue that removal of a hazardous substance and removal of a hazard or likely hazard are two different and discrete things.  They may be in some cases, I have an open mind on the question, but they are not where the hazardous substance is specified and the only way to make the mine safe, if it is to continue to operate, is to remove that hazardous substance.

158   In a circumstance where there is a hazardous substance at a mine site then section 31AB(b) Mines Safety and Inspection Act 1994 and section 31AD(2)(a) Mines Safety and Inspection Act 1994 provide that a prohibition notice is to be used to ensure removal of the hazardous substance and that section 31AE should be invoked to stop work, except for work associated with removal of the hazardous substance, until the hazardous substance is removed.

159   The prohibitions and exceptions in this matter did not require removal of the hazardous substance.

160   If the prohibitions in the prohibition notice did so they would simply say that work at the mine is to cease until all damaged and/or degraded asbestos has been removed with exceptions allowing work associated with its removal.

161   Instead, the prohibitions set up an ongoing system of work to be used by the appellant when work is required to be done at a "place within the Mine where [persons] might be exposed to any asbestos that is being disturbed, abraded or otherwise contacted in any manner".

162   That system may involve removal of the asbestos, but it will not necessarily do so as items 4, 5 and 6 make clear.

163   Insofar as the prohibition notice ever came to be interpreted as a proper invocation of section 31AB(b) and section 31AD(2) Mines Safety and Inspection Act 1994 error occurred.

164   The prohibition notice simply did not require removal of a hazardous substance.

165   I find as follows:

(1) the prohibition notice did not properly invoke section 31AB(b) and section 31AD(2) Mines Safety and Inspection Act 1994; and

(2) insofar as the prohibition notice did properly invoke section 31AB(a) and section 31AC(2) Mines Safety and Inspection Act 1994 it went well beyond what section 31AE Mines Safety and Inspection Act 1994 allows insofar as it imposed a system of work upon the appellant when all it could do was stop work until the appellant had devised a safe system of work for itself.

166   I would uphold appeal grounds 1 to 4 because they essentially capture what I have found to be the problems with the prohibition notice, being:

(1) The prohibition notice was not one properly within section 31AD(2) Mines Safety and Inspection Act 1994 (appeal grounds 1 and 3).

(2) The prohibition notice did not properly comply with section 31AE in that it imposed a system of work upon the appellant when it was for the appellant to ensure it complied with the "management standards" required under the Mines Safety and Inspection Act 1994 (appeal grounds 2 and 4).

167   I have not found it necessary to consider appeal grounds 5, 6 or 7.

168   I add that is a very unfortunate result, given the statutory scheme, that this matter remains alive some two years after the inspector had circumstances brought to his attention which he felt warranted the issue of a prohibition notice.

169   The State mining engineer seems to have given his decision on the appellant's application for review under section 31AY Mines Safety and Inspection Act 1994 in a timely fashion but the matter then took the best part of a year to work its way through the Occupational Safety and Health Tribunal process under section 31BA.

170   Not all of the reasons for that are known to me of course, but at least part of the explanation is that "it was common ground [between the parties] that the Tribunal should approach the present matter as a hearing de novo." (see [12] of reasons for decision, AB 80)

171   I disagree that a hearing de novo should occur under section 31BA. 

172   Section 31BB(2)(a) clearly provides that a review by the Occupational Safety and Health Tribunal "is to be in the nature of a rehearing."

173   The cases the parties apparently relied upon to come to their common position that the hearing should be a hearing de novo predate the insertion into the Mines Safety and Inspection Act 1994 of section 31BB and, in particular, its stipulation that a review by the Occupational Safety and Health Tribunal is to be in the nature of a rehearing.

174   Insofar as Wormald Security Australia Pty Ltd v Peter Rohan, Department of Occupational Health, Safety and Welfare (1994) 74 WAIG 2 is relied upon as support for the proposition that reviews should be by way of a hearing de novo that reliance is misplaced.  That decision was one made when the relevant provisions were quite different and, as I say, did not include section 31BB(2)(a) or its equivalent.

175   I am reinforced in my view by section 31BB(2)(b) Mines Safety and Inspection Act 1994 which exhorts the Occupational Safety and Health Tribunal to complete its work "as quickly as is practicable."

176   Although a hearing de novo can still be conducted as "quickly as is practicable" it is clear to me that if section 31BB(2)(a) and (b) Mines Safety and Inspection Act 1994 are read together Parliament did not intend reviews to be by way of a hearing de novo because this would take too long.

177   The hearing should have been in the nature of a rehearing.  Exactly what this means may be a matter for another day, but what may be said with confidence is that it does not mean a hearing de novo.

178   In this case it is appropriate, in my view, for the Full Bench to exercise power which will quash the prohibition notice but my strong view, at least, is that the matter should not have played out in the way it did. 

179   I do not know, of course, whether the "circumstances" described in the prohibition notice properly gave rise to the issue of a prohibition notice or not but let me assume there was something in the circumstances which did so.  From that point on it seems to me that the structure and scheme of the Mines Safety and Inspection Act 1994 is one which allows, indeed demands, the matter to be addressed practically and quickly.

180   On a review under section 31AZ Mines Safety and Inspection Act 1994 the State mining engineer may "differ the notice with such modification is the State mining engineer consider appropriate."

181   This is a power that Occupational Safety and Health Tribunal also has. 

182   Further, so long as no review by the State mining engineer or the Occupational Safety and Health Tribunal is pending, the State mining engineer can cancel a notice under section 31DE Mines Safety and Inspection Act 1994.  Although this occurs "on his or her own initiative" it seems to me there is no reason why the State mining engineer could not be prompted to consider the matter based on a submission that satisfied him or her that a problem had been fixed.

183   Accordingly there are several ways in which, if it be assumed there was a problem, that problem may be addressed, and everyone get on with their business, short of what was an appeal to the Full Bench at which, without there being any criticism whatsoever directed at the appellant for this, arguments were made which one would expect to hear on an application for judicial review before the Supreme Court. 

184   Of course, the Supreme Court may not have been interested in such arguments until the review process established by the Mines Safety and Inspection Act 1994 was exhausted but in my view this is all the more reason why that review process should be quick and geared to finding practical solutions to practical problems acceptable, insofar as is possible, to all parties.