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[2025] NSWSC 766
General information, not legal advice.
Supreme Court of NSW
2025-07-17
Hamill J (as Duty Judge)
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Source: NSW Caselaw (www.caselaw.nsw.gov.au). Converted to plain text by ZoeLaw. Not the official version.
Medium Neutral Citation: Anthea Hammon v ASKO APPLIANCES (AUST.) PTY. LTD. [2025] NSWSC 766
Hearing dates: 9 July 2025
Date of orders: 17 July 2025
Decision date: 17 July 2025
Jurisdiction: Common Law
Before: Hamill J (as Duty Judge)
Decision: (1) The plaintiffs are granted leave to rely on the report of Marty Denham dated 30 June 2025 (“the report”) subject to the following conditions:
(i) The plaintiffs may not rely on the facts and opinions in part 10 of the report.
(ii) The plaintiffs are to make an election to avoid relying on multiple experts on the same issue, and are not permitted to rely on the evidence of both Marty Denham and John Gardner to respond to the opinions of Colin Grantham stated in his report of 5 October 2023 at paragraphs [45], [46] and [47].
(iii) For the sake of clarity, if the plaintiffs elect to rely on the opinions of Marty Denham, the plaintiffs are not to rely on the opinions expressed by John Gardner in his report of 6 May 2025 on the same issue, that is the opinions stated in paragraphs [72]-[76] and [130].
(iv) Conditions (i)-(iii) do not prohibit the plaintiffs from relying on the evidence and opinions of John Gardner more generally.
(2) Subject to the contents of paragraph [42] of this judgment, the plaintiffs are to pay the defendant’s costs of and incidental to the notice of motion.
(3) Confirm the matter is listed before Chen J for status review on 25 July 2025.
(4) Subject to any contrary order that may be made by Chen J at the status review on 25 July 2025, Marty Denham may participate in the expert conclave foreshadowed in orders 6, 7, 8 and 9 of the case management directions made by Chen J on 15 November 2024.
(5) The Court is to be advised of any application to be made at the status review before Chen J on or before 22 July 2025.
(6) Any notice of motion and evidence in support of such application is to be filed and served on or before 23 July 2025.
(7) Written submissions in support of, or opposing, such an application are to be filed and served on or before 24 July 2025.
Catchwords: CIVIL LAW – plaintiffs seek leave to rely on expert evidence in reply – where both parties failed to comply with case management orders – where plaintiffs’ delinquency in obtaining report most egregious – whether evidence properly categorised as evidence in reply – contest between experts relating to cause of house fire – whether fire caused by electrical fault in appliance or lightning strike – case management – whether plaintiffs bound to retain original expert to provide evidence in reply – multiplicity of experts – fairness to defendant – imminence of hearing date and expert conclave – where part of expert report raises new issues – where part of report responsive to defendant’s expert’s opinion – avoiding multiplicity of experts on same issue – conditional grant of leave – plaintiffs put to election as to the expert upon which they rely – spirited submissions
Legislation Cited: Competition and Consumer Act 2010 (Cth), Sch 2 – Australian Consumer Law, ss 9, 54
Cases Cited: Aon Risk Services Australia Ltd v Australian National University (2009) 239 CLR 175; [2009] HCA 27
Queensland v JL Holdings Pty Ltd (1997) 189 CLR 146; [1997] HCA 1
Texts Cited: Practice Note SC CL 1
Category: Procedural rulings
Parties: Anthea Patricia Hammon (First Plaintiff)
Ian Jay (Second Plaintiff)
ASKO APPLIANCES (AUST.) PTY. LTD. (Defendant)
Representation: Counsel:
S Ahmed (Plaintiffs)
D Kelly (Defendant)
Solicitors:
Ligeti Partners Lawyers (Plaintiffs)
Gillis Delaney Lawyers (Defendant)
File Number(s): 2023/00059965
Publication restriction: N/A
In the midst of a formidable duty list last week, the plaintiffs (Anthea Hammon and Ian Jay) made an application for leave to rely on an expert report by Marty Denham, an electrical compliance consultant, dated 30 June 2025. The plaintiffs seek leave to rely on that report in a 5-day hearing listed to commence on 11 August 2025. The defendant (Asko Appliances Pty Ltd) objects to the use of the report on two main bases. First, the relevant report purports to be evidence in reply whereas it is not properly so categorised. Secondly, the report was filed and served in breach of case management orders made by Chen J on 15 November 2024 and creates unfairness to the defendant which will not be in a position to respond to the evidence. In opposing the grant of leave, the defendant also raised the likelihood that the hearing date will need to be vacated if leave is granted and questioned whether Mr Denham is an appropriate expert to include in an expert conclave. It also raised the timing of the briefing of a new expert, particularly as it related to the conduct of a mediation and the proximity of an expert conclave.
Explaining the factual background to the current dispute is relatively simple. The first plaintiff purchased a clothes dryer from the defendant in March 2015 and installed it in the home owned by her and the second plaintiff. On 10 January 2021 a fire caused extensive damage to the plaintiffs’ house. The plaintiffs allege that the cause of the fire was an electrical fault in the clothes dryer. The statement of claim alleges the plaintiffs suffered loss and damage amounting to a little less than $1,300,000. It seems that the case will be contested largely on the basis of conflicting expert evidence. The defendant denies that the fire was caused by any fault in the product it sold to the first plaintiff. It is unnecessary for present purposes to dwell on the legal and statutory bases of the plaintiffs’ cause of action, but it is succinctly put in the plaintiffs’ written submissions on the present application:
“15. There are two bases in which the plaintiffs seek damages against the defendant. First, a breach of a guarantee that goods are of acceptable quality pursuant to section 54 of the ACL. Secondly, damages arising from the dryer having a safety defect causing loss and damage.”
“1. Order by 29 November 2024, the parties to exchange categories of documents for discovery.
2. Order by 14 February 2025, the parties to provide their list of documents for discovery.
3. Order by 21 February 2025, the parties to electronically provide their discovered documents.
4. Order the Plaintiff to serve any evidence in reply by 14 March 2025.
5. Order the parties to participate in mediation by 11 April 2025, with such mediation to be conducted in accordance with Part 4 of the CPA and rr 20.1-20.7 of the Uniform Civil Procedure Rules 2005 (NSW).
6. Order that the parties agree upon composition of conclaves, as well as organise dates for those conclaves to occur by 18 April 2025, 5pm.
7. Order that letters of instruction (including material to be provided) to those expert conclaves, be exchanged by 13 May 2025, 5pm, and agreed upon by 20 May 2025, 5pm.
8. Order that experts are to confer and engage in conclaves by 28 June 2025, 5pm, with joint reports to be provided within 48 hours of the conclave occurring.
9. Matter listed for hearing for 5 days commencing on 11 August 2025.
10. The usual order for hearing in Annexure A to Practice Note SC CL 1 is made. Order (c) in the usual order for hearing in Annexure A to Practice Note SC CL 1 is extended to apply to all expert evidence.
11. Grant liberty to apply on 48 hours’ notice.
12. Matter listed for further status review before Chen J on 25 July 2025.”
For present purposes the critical dates in those directions were:
The plaintiffs were required to serve any evidence in reply by 14 March 2025.
The parties were to attend mediation by 11 April 2025.
The parties were to agree upon the composition of, and dates for, an expert conclave by 18 April 2025.
The conclave was to be held by 28 June 2025 with joint reports to be provided within 48 hours.
By the time Chen J made the case management orders referred to in paragraphs [3]-[4], the defendant had served expert reports from Dr Colin Grantham dated 5 October 2023 and 6 September 2024. [1] The report of 5 October 2023 was served on the plaintiffs on 10 October 2023. The second report was served on 6 September 2024, the day it was signed.
The plaintiffs filed and served expert reports in reply as follows:
Report of John Gardner dated 6 May 2025.
Report of Belinda Jones dated 7 May 2025.
The authors of those reports were the same experts whose reports formed part of the plaintiffs’ evidence to which Dr Grantham’s reports responded. Those reports in reply were served close to two months outside of the period stipulated by Chen J in the directions made on 15 November 2024. Even so, the defendant takes no objection to reliance on those reports and has no objection to Mr Gardner and Ms Jones participating in the conclave.
The immediate dispute, which provoked forceful, feisty and (in the context of the forum, that is the duty list) quite lengthy submissions by counsel for both sides, arose because of the service of an expert report of Mr Marty Denham dated 30 June 2025. That report was served more than three months after the evidence in reply was directed to be served and two days after the date by which the conclave was supposed to have taken place.
“In relation to the conclave, the representatives of both sides did not engage with each other in relation to organising a conclave, and I can proffer no good reason on my side of the table as to why that occurred, and I obviously wouldn’t speak for my friend’s instructing solicitors as to why that has not occurred.
But there was no attempt, there was no communication, as far as I am aware, for any of either my instructing solicitors or my friend’s instructing solicitors to liaise with each other to have the experts conclave, and that was, I think, something that should have happened in accordance with the orders perhaps a few weeks ago.”
I did not understand counsel for the defendant to gainsay the proposition that there was fault on both sides in terms of non-compliance with the time limits for the directions relating to arranging the mediation (which occurred on 16 May 2025, more than a month after the date contemplated in order 5) or the exchange of letters of instructions of the experts who were expected to participate in the conclave.
However, the most egregious delinquency was on the part of the plaintiffs who did not engage Mr Denham until 10 June 2025, that is after the mediation failed to resolve the disputes between the parties. As to that, the plaintiffs’ solicitor said in his affidavit in support of the current motion:
“8. On 16 May 2025, I became aware of the need for the plaintiffs to adduce further expert evidence in reply which addressed:
(a) [45] to [47] of Dr Grantham’s report dated 5 October 2023, being the laboratory experiments conducted by Dr Grantham in relation to the effect of voltage magnitude on a capacitor; and
(b) whether a lightning strike could have caused the capacitor in the Asko Dryer to belatedly fail.”
It will be noted, as was stressed at the hearing, that 16 May 2025 was the date of the mediation. One of the defendant’s complaints is that the plaintiffs are attempting to patch up their case by reference to matters raised in the mediation or, as it was put in argument by Mr Kelly, using the mediation as a form of “advice on evidence”. Mr Ahmed submitted it was “slightly unfair” to say that the plaintiffs used the mediation as a means of “flushing out any problems in this case and then patching [them] up”. He explained that, as the hearing date approached, the plaintiffs had looked to the evidence adduced in the case to determine whether there was a sufficient response to each aspect of the defendant’s evidence. While that may be accepted, the coincidence of the date nominated by the solicitor in his affidavit and the date of the mediation is conspicuous.
The defendant’s position at the hearing was that the plaintiffs have been aware of the contents of Dr Grantham’s report for over 18 months, and that the decision to obtain a report from Mr Denham after the mediation on 16 May 2025 was not adequately explained and was inconsistent with principles of good faith negotiations. Mr Kelly argued:
“… there is a notable lack of any explanation for anything, for any reason, for the decision to get a report from Mr Denham. Why that took 25 days for a letter of instruction to go, but I will come back to that, because the letter of instruction to Mr Denham goes 25 days after the solicitor formed that view, with no notice to the defendant, no notice to the Court.
But, your Honour, it becomes a very – it sets a very dangerous precedent if parties think they can turn up to mediations, expect their opponents to either come to the table and effectively treat it as an advice on, to then go off in secret and qualify another expert, and this is to deal with material they have had by then well over 18 months.”
Moreover, the defendant argued that there was no explanation for the delay between the decision on 16 May 2025 to obtain an additional report and the letter of instruction to Mr Denham which was dated some 25 days later.
I accept there is force in the defendant’s position on these matters. Further, as Mr Kelly submitted, more recent authorities emphasise the need for courts to deal efficiently and expeditiously with civil suits, such as the present one, and to insist on parties complying with the relevant rules of court and case management orders made to ensure such efficiency.
Previously the High Court had taken the position exemplified in Queensland v JL Holdings Pty Ltd (1997) 189 CLR 146 at 155; [1997] HCA 1 that justice between the parties is the “paramount consideration” and that, while case management is a relevant concern, it should not be allowed to “prevail over the injustice of shutting the applicants out from raising an arguable [case], thus precluding the determination of an issue between the parties”. However, in Aon Risk Services Australia Ltd v Australian National University (2009) 239 CLR 175; [2009] HCA 27 (“Aon Risk Services v ANU*”*) the Court took a different approach. For example, French CJ said at [30]:
“It might be thought a truism that ‘case management principles’ should not supplant the objective of doing justice between the parties according to law. Accepting that proposition, JL Holdings cannot be taken as authority for the view that waste of public resources and undue delay, with the concomitant strain and uncertainty imposed on litigants, should not be taken into account in the exercise of interlocutory discretions of the kind conferred by r 502. Also to be considered is the potential for loss of public confidence in the legal system which arises where a court is seen to accede to applications made without adequate explanation or justification, whether they be for adjournment, for amendments giving rise to adjournment, or for vacation of fixed trial dates resulting in the resetting of interlocutory processes.”
“[111] An application for leave to amend a pleading should not be approached on the basis that a party is entitled to raise an arguable claim, subject to payment of costs by way of compensation. There is no such entitlement. All matters relevant to the exercise of the power to permit amendment should be weighed. The fact of substantial delay and wasted costs, the concerns of case management, will assume importance on an application for leave to amend. Statements in JL Holdings which suggest only a limited application for case management do not rest upon a principle which has been carefully worked out in a significant succession of cases. On the contrary, the statements are not consonant with this Court’s earlier recognition of the effects of delay, not only upon the parties to the proceedings in question, but upon the court and other litigants. Such statements should not be applied in the future.
…
[114] Rule 21 of the Court Procedures Rules recognises the purposes of case management by the courts. It recognises that delay and costs are undesirable and that delay has deleterious effects, not only upon the party to the proceedings in question, but to other litigants. The Rule’s objectives, as to the timely disposal of cases and the limitation of cost, were to be applied in considering ANU’s application for amendment. It was significant that the effect of its delay in applying would be that a trial was lost and litigation substantially recommenced. It would impact upon other litigants seeking a resolution of their cases. What was a ‘just resolution’ of ANU’s claim required serious consideration of these matters, and not merely whether it had an arguable claim to put forward. A just resolution of its claim necessarily had to have regard to the position of Aon in defending it. An assumption that costs will always be a sufficient compensation for the prejudice caused by amendment is not reflected in r 21. Critically, the matters relevant to a just resolution of ANU’s claim required ANU to provide some explanation for its delay in seeking the amendment if the discretion under r 502(1) was to be exercised in its favour and to the disadvantage of Aon. None was provided.”
Mr Ahmed submitted that the purpose of obtaining a report from Mr Denham was to reply directly to three specific paragraphs of Dr Grantham’s report dated 5 October 2023. Those paragraphs were [45], [46] and [47] and related to a component of the dryer called “metallised film capacitors” in relation to which Dr Grantham conducted experiments “many years ago”. Dr Grantham said these capacitors “are particularly susceptible to high voltage surges.” Based on evidence that there was an electrical storm in the area relatively shortly before the fire, Dr Grantham posited that the fire was not caused by any defect in the capacitor but as a result of a voltage surge caused by, or incidental to, the electrical storm.
The relevant part of the report is as follows:
“[45] Based on my experience metallised film capacitors are particularly susceptible to high voltage surges. Many years ago I carried out laboratory experiments at the University of NSW to investigate the effect of voltage magnitude on the subject type of capacitor (i.e. metallised film). I carried out endurance tests on about 20 new capacitors in the voltage range 240V+6% (i.e. the nominal maximum voltage range in Australia).
[46] As I slowly increased the voltage from 240V to 254.4V I could clearly hear the capacitors crackling due to their ability to ‘self-clear’. After the 254.4V was reached the self-clearing sound stopped and the 20 or so capacitors continued to operate normally and without incident.
[47] After several weeks of testing, without incident, I opened the aluminium case of some of the capacitors to examine the metallised film and could see numerous approximately 1mm diameter holes in the aluminium foil. The numerous number of self-clearing holes for the relatively small amount of voltage increase used in my tests indicates how this type of capacitor can be affected by voltage surges. The large capacitance value for a relatively small volume and their inherent self-clearing ability is one of the reasons such capacitors are used extensively throughout the world.”
This evidence has a capacity to undermine the plaintiffs’ case that there was a manufacturing defect in the capacitor of the dryer, which would constitute a “safety defect” under s 9 of the Competition and Consumer Act 2010 (Cth), Sch 2 – Australian Consumer Law (“ACL”), making the defendant liable for the fire (see ACL s 54). The defendant disputes that the fire started in the dryer but says that, even if the fire did emanate from the dryer due to a failure of the capacitor, such a failure was caused by a lightning strike rather than as a result of any mechanical fault.
In parts 8 and 9 of his report, Mr Denham provides an explanation of the way in which capacitors operate and the causes of failure in such components. In part 10 he goes on to discuss relevant safety standards and in part 11 he deals with what he calls “the issue at hand”, namely whether any failure of the capacitor was caused by a lightning event.
To understand the arguments and my conclusions it is useful to set out the relevant part of the report in full despite its length:
“8. General Information about Motor Capacitors
8.1 Motor capacitors are widely used in conjunction with single-phase induction motors used in many motor-driven electrical appliances such as fans, air conditioners, washing machines, clothes dryers and the like.
8.2 Normally such motors have a main winding and an auxiliary winding. The capacitor is used to alter the ‘phase’ of the current that flows through the auxiliary winding so that the instant of peak current in the auxiliary winding differs from that in the main winding. This phase difference gives the motor direction of movement/spin and increases both the starting torque and the power of the motor.
8.3 A capacitor is a device that stores electrical charge and generally consists of two electrodes or plates (metal surfaces) of a certain area (depending on the required capacitance), separated by an insulator (dielectric).
8.4 In the case of a typical ‘self-healing, metallised polypropylene capacitor’ (MPP capacitor) an electrode is an extremely thin layer of metal attached to a polypropylene film (the dielectric) by vapour evaporation. The metal is usually aluminium, although some zinc may be used in an alloyed form. The metal layer is extremely thin (10 to 50 nanometres) and fragile and therefore vulnerable to contaminants such as water vapour that can cause corrosion. The polypropylene film is typically around eight micrometres in thickness.
8.5 As explained by (Brown - Electrical and Thermal Modelling of Low Power, Metallised Polypropylene Capacitors – RMIT University - 2007) the capacitor is constructed of two long strips of the metallised polypropylene film with clear edges on opposite sides, spiral wound onto an insulating mandrel to form a coil, as shown in Figure 8.1 below. After the two strips are co–wound, a plasma arc is used to spray a zinc coating on each end of the cylinder (Shaw, Cichanowski, Newcomb, & Yializis, 1982) (Borgetti, Nucci, Pasini, Pirani, & Rialdi, 1995). The zinc coating has a thickness of around 400-500μm and is known as ‘schooping’. The schooping selectively connects to the edge of one strip (Shaw, Cichanowski, & Yializis, A changing capacitor technology – failure mechanisms and design innovations, 1981). The clear edge and offset prevent simultaneous connection of the other strip to the same end, as shown in Figure 8.2 below. Wires are then soldered to each schooping to provide external connections to the capacitor. Passing one of these wires back through the mandrel is not only convenient, but reduces overall inductance (Ropa & Glaize, 1994) (Joubert, Rojat, & Beroul, 1995).
Figure 8.1 – Standard spiral-winding construction of cylindrical capacitors (Brown 2007)
Figure 8.2 – Diagrammatic cross-section of a cylindrical metallised capacitor winding (Brown 2007)
Figure 8.3 – View of example capacitor coil with outer layers of metallised film peeled back
8.6 (Brown, A Dominant Mechanism for Thin Film Power Capacitors Going High or Self- Destructing, 2006) explains that the metal layer of the electrode is thin to allow ‘self-healing’ of momentary breakdowns of the insulating property of the dielectric films. In this process, discharge current through the short removes conducting metal film around the breach thereby isolating the failed area and allowing the capacitor to continue operating with very small change in performance. A typical clearing gap in the metallization is shown in Figure 8.4 below.
Figure 8.4 – Electron micrograph of clearing site on metallised capacitor film (Brown 2007)
8.7 MPP capacitors provide high volumetric capacitor density, low cost, excellent frequency characteristics and a unique ability to recover from point failures in the dielectric film (self-heal). These properties and especially the self-healing capability make the MPP capacitor the capacitor of choice around the world for low power applications (Brown 2007).
9. Motor Capacitor Failures
9.1 Metallised polypropylene capacitors have a generic weakness that is not well understood, that is, failure of the self-healing process leading to a catastrophic failure (Brown 2007).
9.2 It is well known amongst electrical engineers that self-healing, metallised polypropylene capacitors can fail. The failures range from a simple loss of capacitance with no change to the physical appearance, through to bulging or localised melting of the capacitor, and in severe cases, catastrophic combustion and destruction of the capacitor.
9.3 According to (Brown, Electrical and Thermal Modelling of Low Power, Metallised Polypropylene Capacitors, 2007) capacitor failure can be broadly classified into three types: soft, disconnection and catastrophic. Soft failure can be characterised by gradual reduction in capacitance or increase in dissipation factor or both, without obvious outward signs of degradation (Sarjeant, Capacitor fundamentals, 1989). Disconnection failure can be characterised by destruction of the electrical continuity of the capacitor. A typical example might be where a soldered connection detaches from the schooping. Typical catastrophic failure of capacitors involves on–going electrically–supported progressive melting of the polypropylene, often characterized by polypropylene exudates from the capacitor body and eventual melting of the outer case. In extreme cases copious quantities of smoke are generated and the capacitor may catch fire.
9.4 In general, considering the hundreds of millions of such capacitors in use around the world, the rate of failure resulting in ignition of fire is typically quite low at around 0.001%.
9.5 In my opinion, catastrophic capacitor failure is best described as a ‘severe internal dielectric breakdown and thermal runaway event’.
9.6 As discussed in Section 8.6 above, small electrical breakdowns between the electrodes through the dielectric normally ‘self-heal’ (aka ‘self clear’). In other words, if a hole develops in the dielectric a short-circuit can occur between the electrodes thereby creating an electrical arc that clears the aluminium electrode (metallisation layer) from around the hole by vaporising it. This interrupts and ceases the short-circuit arc within a fraction of a second. The brief, localised heating and small amount of gases produced normally do no further harm, therein the breakdown ‘self-heals’.
9.7 Point failures in the polypropylene dielectric may be due to manufacturing defects such as pinholes, foreign particles or microflaws in the semi-crystalline structure of the polymer (Reed & Cichanowski, 1994).
9.8 According to (Borgetti, Nucci, Pasini, Pirani, & Rialdi, 1995) defects in metal polypropylene films comprising the dielectric of self-healing capacitors can result in weak spots.
9.9 According to (Brown, Electrical and Thermal Modelling of Low Power, Metallised Polypropylene Capacitors, 2007) composition of the polypropylene is critical to the reliability and performance of the capacitor. The finished film may include residues of polymerization catalysts, stabilisers or anti-oxidants and slip agents (Al-Malaika, 1999) (Bramoulle, Marret, Michalczyk, & Rubin De Cervens, 2001). In addition, the polymer is a mix of crystallised and amorphous regions and the surface topography is marked by spherulites, fibrils, lamella and micro-cavities lifted by gas inclusions (Renz, 1982).
9.10 Brown further explains that the effectiveness of self–clearing is affected by the nature of the products formed from ablated polymer. These products are preferably non–conducting solids or gases. Gaseous products, other than hydrogen, are usually hydrocarbon gases such as propane, or carbon monoxide. The presence of oxygen included as part of the polymer chain or diffused in the polymer matrix, is thus important to the success of self–clearing with some polymers (Picci & Rabuffi, 2002). If gaseous products are not formed, products of ablated polymer can condense as carbon around the breakdown site. This carbon compromises the electrical isolation formed by the clearing event (Reed & Cichanowski, 1994).
9.11 A ‘severe internal dielectric breakdown and thermal runaway event’ occurs when multiple breakdowns transpire within close proximity and time within the capacitor such that abnormally high localised heating occurs that further degrades the dielectric, thereby accelerating the breakdowns and heating. Flammable gases produced by the severe heating of the polypropylene film cause the capacitor to rupture, at times explosively. Often the capacitor will ignite. If sufficient oxygen is present, the polypropylene dielectric will combust readily.
9.12 (ERA Technology, 2013) (Failure in Metalized Polypropylene Capacitors) also describes how the energy dissipated in the breakdown appears as heat and the temperature rises locally. The plastic film at the breakdown point is carbonised with the release of gas. If a series of breakdowns occur close together within the capacitor or closely spaced in time, the capacitor may not be able to dissipate the heat generated in the breakdown events. The temperature then rises locally with each breakdown and the gas accumulates. If sufficient breakdowns occur, the temperature rises high enough to melt the plastic film. Then larger breakdowns can occur and significant amounts of gas are generated. The gas can blow out the side of the case or blow the case off entirely. Under extreme conditions, the gas mixture can ignite.
9.13 According to (Bond) (A New Mitigation Strategy for Failure in Metalized Polypropylene Capacitors), when capacitors undergo many self-heal cycles in the same area, a hot spot is created which decreases the breakdown voltage of the dielectric resulting in the possibility of thermal runaway, catastrophic failure and ignition of the dielectric.
9.14 Poor quality or inferior dielectric films have been known to fail prematurely leading to catastrophic failure of capacitors. According to (Galperin & White, 1985) (Capacitor Film Surface Assessment Studies), breakdown voltages can be related to film surface defects and dielectric strength has been found to decrease with non-conformity of film orientation, increased film thickness variation (which generates local heating) and variations in chemical composition.
9.15 According to (Brown - Electrical and Thermal Modelling of Low Power, Metallised Polypropylene Capacitors – RMIT University - 2007) the gossamer–like thinness of the film makes winding of capacitors difficult, especially with respect to creasing. Creasing of the polymer film within a capacitor roll is highly undesirable as it typically results in mechanical abrasion of the thin metal on the top of the crease leading to electrical discontinuity. The uneven pressure across the thickness of adjacent layers can also result in degraded insulation resistance. Winding tension has to be carefully controlled and profiled according to winding diameter, to obtain a tight winding. Higher interlayer pressure in the inner windings compared to the outer windings is inescapable because of the cumulative effect of the overlaying layers and the smaller radii of the inner layers.
9.16 (Brown 2007) further explains that clearing discharges in the outer layers tend to involve more energy and are shorter in duration than in the inner layers (El-Husseini, Venet, Rojat, & Fathallah, 2001) (Reed & Cichanowski, 1994). Inner layer discharges are more dangerous than outer layer discharges because the energy must be largely absorbed by the polypropylene. In addition, the gaseous discharge products, which have lower dielectric breakdown characteristics than polypropylene, tend to remain trapped between the layers (Shaw, Cichanowski, Newcomb, & Yializis, 1982) (Sarjeant, Capacitor fundamentals, 1989). The deliberate thinness of the metallic film means that capacitors rarely short to an impedance low enough to cause an external electrical fuse to blow (Nagamani & Ganga, 1992). The high impedance breakdown can easily result in sustained online failure resulting in ongoing heat generation, melting of the polypropylene and eventual combustion of the capacitor materials. This catastrophic failure mode is a generic problem with metallised polypropylene capacitors.
9.17 ‘Severe internal dielectric breakdown and thermal runaway events’ can cause the polymer exudates to simply breach the capacitor casing as shown in Figure 9.1 below, or fail more violently with open combustion as evident from the state of the capacitor as shown in Figure 9.2 below.
Figure 9.1 – View of typical melted polymer exudate from failed capacitor
Figure 9.2 – View of typical ruptured and charred failed capacitor
9.18 According to (Brown, Electrical and Thermal Modelling of Low Power, Metallised Polypropylene Capacitors, 2007) the triggers for such catastrophic failures are not well understood and may have many different origins. Triggers for failure may include excessive voltages or currents particularly in the form of transients. These can destroy the dielectric or result in electrical disconnection of the schooping from the metal films (Borgetti, Nucci, Pasini, Pirani, & Rialdi, 1995) (Nucci, Pirani, & Rinaldi, 1991) (Picci & Rabuffi, 2002) (Xin, Fuchang, Zonggan, & Nanyan, 2000). Intrinsic weaknesses in the dielectric due to catalyst clumping or anti-oxidants may also be involved in some failures (Reed & Cichanowski, 1994).
9.19 Trapped charge on the surface or in the bulk of the polymer can trigger breakdown of the dielectric (Fukuma, Nagao, & Kosaki, 1991). Failure is also linked to hot spots within the capacitor body (Shaw, Cichanowski, Newcomb, & Yializis, 1982). Corrosion typically reduces the surface area of metallization and can increase the power loss in the capacitor by increasing the effective series resistance, thereby potentially increasing the temperature inside the capacitor during operation.
9.20 By way of summary, catastrophic failure (severe internal dielectric breakdown and thermal runaway) of metallised polypropylene capacitors can be caused by several mechanisms including:
1. Ingress of moisture (leading to atmospheric corrosion of metallisation)
2. High operating temperature (leading to multiple dielectric breakdowns close in space and time)
3. Overvoltage and transients (causing multiple dielectric breakdowns close in space and time)
4. Defective manufacturing processes of the dielectric film, metallisation or coil (leading to electrochemical corrosion of metallisation or multiple dielectric breakdowns close in space and time)
Failure mechanisms ‘1’ to ‘3’ above relate to defective manufacture of the appliance in which the capacitor is fitted and mechanism 4 relates to defective manufacture of the capacitor itself, as discussed further in Section 10.8 below.
10. Compliance with Product Standard
10.1 All the above discussed mechanisms that can lead to catastrophic failure of a capacitor are addressed in the product safety standards.
10.2 At the Time of Purchase of the Dryer, the relevant product safety standard for ‘tumble dryers’ was AS/NZS 60335.2.11:2009 titled ‘Household and similar electrical appliances – Safety - Part 2: Particular requirements for tumble dryers’ (AS/NZS 60335.2.11).
10.3 The scope of AS/NZS 60335.2.11 states ‘The objective of this Standard is to provide manufacturers, designers, regulatory authorities, testing laboratories and similar organizations with safety requirements designed to give the user protection against hazards that might occur during normal operation and abnormal operation of the appliance and which may be used as the basis for approval for sale or for connection to the electricity supply mains in Australia and New Zealand.’
10.4 AS/NZS 60335.2.11 is an adoption with national modifications and contains the full text of the international standard IEC60335-2-11 and has been varied to take account of Australian and New Zealand conditions.
10.5 The scope of AS/NZS 60335.2.11 further states that ‘it is to be used in conjunction with the latest edition of AS/NZS60335.1, Household and similar electrical appliances – Safety - Part 1: general requirements.’
10.6 At the Time of Purchase, the applicable Part 1 standard was AS/NZS 60335.1:2011 (AS/NZS 60335.1).
10.7 Therefore, AS/NZS 60335.2.11 together with AS/NZS 60335.1 formed the relevant product standard (the Product Standard) for ‘tumble dryers’.
10.8 The Product Standard sets various construction and testing requirements to ensure the product is safe. This includes a range of requirements for motor capacitors, including requirements targeted at the mechanisms of capacitor failure discussed in Section 9.20 herein, as follows:
1. Requirements to ensure the capacitor is not subject to water.
2. Requirements to ensure the capacitor is not subject to temperatures exceeding the rated temperature limit of the capacitor.
3. Requirements to account for common electricity supply overvoltages and transients (a form of momentary overvoltage).
4. Requirements for the capacitor itself to be adequately designed for safety.
10.9 In respect to the above-mentioned adequate design of capacitors, the Product Standard requires motor capacitors to comply with a specific motor capacitor standard IEC60252-1 titled ‘AC motor capacitors - Part 1 – General - Performance, testing and rating - safety requirements - guidance for installation and operation’ (the Capacitor Standard).
10.10 Considering the above, in the event that catastrophic failure of a capacitor in a clothes dryer caused a fire, the likely root cause would be defective manufacture.
10.11 Notwithstanding, Grantham has proffered that the likely failure of the Capacitor was the consequence of the Lightning Event and not due to a manufacturing defect. I discuss the possible involvement of the Lightning Event below.
11. Lightning Event
11.1 With the above understanding of motor capacitors and motor capacitor failures, I can now address the issue at hand.
11.2 There is no doubt that lightning creates extremely high voltages, however, voltage from lightning strikes does not normally affect building electrical circuits. This is largely due to the design of the electricity supply reticulation system which includes various types of lightning (overvoltage) arresters and diverters. It is possible however, although rare, for lightning to strike the local electricity supply reticulation and cause a momentary overvoltage surge to enter a building and cause electrical damage to the electrical circuits. I have seen damage from such events on several occasions as part of my work.
11.3 In the event, that an overvoltage surge from lightning happens to impact the electrical circuits of a building, the level of overvoltage surge and resultant damage is normally minor due to the majority of the voltage and current from the lightning being disbursed to ‘earth’ through numerous other paths.
11.4 In the subject case, the level of overvoltage surge from the Lightning Event is indicated by the damage found following the event. It is understood that the Lightning Event caused two circuitbreakers in the ‘electrical distribution sub-board’ of the Property to ‘trip’. This indicates that overvoltage from the Lightning Event caused a momentary overcurrent on two of the several sub-circuits of the Property. The operation of the circuit-breakers itself likely limited the overcurrent and damage to the downstream circuits.
11.5 In paragraphs 38 to 48 of the Affidavit of Hammon, Hammon explains the effects of the Lightning Event. Hammon says the two circuit-breakers had ‘tripped’ but the sub-board otherwise appeared normal. Upon resetting the circuit-breakers, power was immediately restored to the Property. Also, the internet stopped working due to a fault with the NBN ‘network termination device’. Apart from this, all the appliances in the Property continue to work normally.
11.6 The above description of the effects of the Lightning Event indicates to me that the overvoltage surge was minor. The only damage realised by the household following the event was failure of the electronic NBN device. Electronics are particularly vulnerable to overvoltage surges. I have experienced such an overvoltage surge from lightning at my home and the only damage that occurred was failure of electronics of the internet router and an audio amplifier. If anything is going to fail from a lightning overvoltage surge, it is normally electronic devices.
11.7 As already discussed, I have never encountered a motor capacitor failing due to an overvoltage surge from lightning. Motor capacitors are not electronic and are normally sufficiently robust (in accordance with the Capacitor Standard) to withstand overvoltage events, including as already discussed, the ability to ‘self-heal’ from overvoltage breakdowns.
11.8 In the event that there was widespread catastrophic damage to electrical circuits and appliances in the Property, I would consider that damage to the Capacitor was possible. However, in my view, the level of damage experienced from the Lightning Event (as described by Hammon) indicates that it is unlikely that the Capacitor was damaged by the event.
11.9 Furthermore, it is understood that the Dryer continued to successfully operate without issue during the several weeks between the Lightning Event and the Fire. In the event that the Lightning Event damaged the Capacitor as proffered by Grantham, the Capacitor would have failed contemporaneously with the event, not several weeks later.
11.10 It is apparent that the control electronics of the Dryer were not damaged because the appliance continued to operate successfully for several weeks. The control electronics would have been far more susceptible to damage from an overvoltage surge than the Capacitor, therefore, the Lightning Event could not have affected the capacitor without affecting the control electronics.
11.11 Also, when a clothes dryer is not operating, the motor and its capacitor is disconnected electrically from the supply circuit by the internal switching components (relays). Therefore, if the Dryer was not operating at the time of the Lightning Event, damage to the Capacitor from the event can be entirely discounted. In respect to this, I made enquiries with my instructing solicitors, and I was advised that it is not known whether the Dryer was operating or not at the time of the Lightning Event. Nevertheless, the chances of the Dryer operating at the time of the Lightning Event should be taken into account given that it is an appliance that does not run continuously and is only operated a few times per week.”
“In the event that the Lightning Event did damage the Capacitor sufficiently to cause it to catastrophically fail, that is, to cause a breakdown of its dielectric film sufficient to override its ‘self-healing’ properties, the catastrophic failure of the Capacitor would have occurred at that time (if the appliance was operating at the time) or during the next operation of the appliance. This did not occur; therefore, the Capacitor could not have been damaged by the Lightning Event.”
This is highly probative evidence relating to the opinions expressed in paragraphs [45]-[47] of Dr Grantham’s report dated 5 October 2023 and is responsive to those opinions. Putting to one side part 10 which, as the defendant submits, seems to amount to a recasting of the plaintiffs’ case, the evidence in parts 8, 9 and 11 of the report is evidence in reply to the evidence in Dr Grantham’s report.
Mr Kelly submits that such evidence does not constitute reply evidence as envisaged by Chen J in his case management orders in November last year:
“It was never envisaged that, all of a sudden, a month before a mediation (sic), a party can serve a report from an entire new expert, saying, we are responding to some part of one of your reports, and this now comes into the mix”.
“[72] Dr. Grantham presents an argument in his paras 45 to 47 that a lightning strike on 28 December 2020 could have caused the motor capacitor in the Dryer to fail and case the fire on 10 January 2021.
[73] His argument is based on experiments that he conducted at UNSW on metallised film capacitors, of the type that was installed in the Dryer, in which the application of increasingly high voltages led to the eventual failure of the capacitors under test.
[74] In my opinion, if there had been a lightning strike that produced a high voltage ‘spike’ on the power circuit to which the Dryer was connected, it is highly unlikely to have initiated the eventual failure of the capacitor for the following reasons:
(a) Firstly, if the voltage spike was high enough to damage the capacitor connected to the motor, it would also have been high enough to have damaged the small electronic components in the control panel of the Dryer. If this had occurred the Dryer in my opinion would not have worked immediately aner the power was restored.
(b) Secondly, the Dryer was fitted with ‘power line filter’ at the point where the power cord was connected inside the Dryer cabinet. - See Photograph 1 on page 61 of the Affidavit of David Dokl copied below with power line filter circled.
[75] The power line filter (also known as a ‘Electromagnetic and Radio Frequency Interference Filter’ or abbreviated to EMI/RFI filter) is intended to prevent electrical ‘noise’, or radio frequency interference generated by the motor in the Dryer, from being fed back into the household wiring and causing interference in television sets, radios, and audio systems. A power line filter will also absorb spurious voltage spikes imposed on the electrical supply to the property by external sources, including those produced by lightning strikes.
[76] In my opinion, the power line filter would have absorbed or suppressed any voltage spike caused by a lightning strike that might have otherwise initiated failure of the motor capacitor in the Dryer.
…
[130] In para 45, Dr. Grantham discusses his experiments with metalised film capacitors, to suggest that lightning on 28 December 2020 might have initiated eventual failure of the capacitor and the fire on 10 January 2021. I disagree for the reason (Reason 5) in paras 72 to 76 above.”
“The Court is concerned about the number of experts often expected to give evidence particularly in personal injury cases. The practice of having a large number of experts qualified, both medical and otherwise, whose opinions may be overlapping and whose reports either are not used or are of little assistance to the Court when tendered, is costly, time-consuming and productive of delay.”
I do not accept the extremity of the defendant’s submission which bordered on suggesting that, in presenting evidence in reply, a party is bound to rely on the same experts who prepared its original reports. As Mr Ahmed submitted, again ignoring the contents of part 10 of his report, Mr Denham’s report is focused on the issue of capacitors and the relevance of lightning strikes, a matter raised by Dr Grantham and which appears to assume great significance in the way the defendant intends to conduct its case. I also accept the plaintiffs’ contention that Mr Gardner “doesn’t deal with capacitors to the same depth as Dr Grantham does” and that Mr Gardner may not have the same extent of relevant expertise that Mr Denham does as an “electrical safety consultant”.
Ultimately, the defendant submits that the proceedings have been carefully case managed, with the expectation that reply evidence would be served prior to the mediation, and that it is now unfair for the plaintiffs to attempt to effectively “recast their case”. This in turn leads to the issue of prejudice to the defendant.
In their written submissions, the plaintiffs submitted that the service of Mr Denham’s report did not cause any prejudice to the defendant on the basis that:
The content of Mr Denham’s report is within the expertise of Dr Grantham;
Conclaves have not yet occurred; and
There is sufficient time in which Dr Grantham could consider the report before a conclave is held, which would not jeopardise the hearing date.
Mr Ahmed expanded upon these points in oral argument, submitting that Dr Grantham is an expert in capacitors who has conducted experiments at the University of New South Wales, albeit many years ago, and was the one who introduced the topic in his report. While accepting that there had been a breach of the case management orders, counsel contended that Dr Grantham would have two weeks to respond to Mr Denham’s report in relation to “areas that he is very, very, very well versed in”, and concerning only “two specific narrow issues”.
Mr Kelly made a spirited submission that there was not a sufficient period of time in which Dr Grantham could be expected to consider Mr Denham’s report and undertake the necessary research to respond, noting that the report includes reference to something like 15-20 publications and canvasses issues about safety standards and product compliance that have not been raised previously. However, when pressed on this submission, Mr Kelly said:
“I’ve had a lot of cases in the past with Professor Grantham and with Mr Gardner, ironically. I’ve got no idea about his availability to respond to actually consider and deal with this report.”
It seemed that the reason Dr Grantham had not been consulted as to his capacity to deal with the issue is that the law partner with carriage of the matter is presently overseas. [2]
The defendant also submitted that Mr Denham has been introduced as a “new expert who has got very specific expertise in dealing with the effect of voltage overcharge and capacitors generally and also with product safety standards”. Consequently, the defendant submitted it will be necessary to retain a new expert to be briefed who is similarly qualified, as Mr Denham’s report covers “whole new areas, [and] it goes to the critical legal issue in between the parties”.
Balancing all relevant considerations, I have concluded that the plaintiffs should have leave to rely on the evidence of Mr Denham, with the exception of part 10 of the report. However, there must be certain conditions attached to that grant of leave. I am satisfied that Mr Denham’s report is important and relevant evidence in reply to the opinions posited by Dr Grantham in paragraphs [45]-[47] of his report. I am not satisfied on the material before me that Dr Grantham will not be in a position to respond to the opinions of Mr Denham and am not persuaded that he lacks the relevant expertise to deal with those opinions.
I have taken into account the failure of the plaintiff to serve the report within the time frames contemplated in the case management orders. However, the facts and circumstances are far removed from the circumstances of a case like Aon Risk Services v ANU. Both parties have taken a somewhat cavalier approach to the timeframes contemplated by Chen J.
I would not allow part 10 of the report because the facts and opinions in that part of the report appear to re-cast the plaintiffs’ case in a way that would create unfairness to the defendant at this late stage.
To avoid a multiplicity of experts providing opinions on the same subject, the grant of leave will be conditional upon the plaintiffs making an election as to whether to rely on the evidence of Mr Gardner or the evidence of Mr Denham on the issues raised by Dr Grantham in paragraphs [45]-[47] of his report.
Contrary to the defendant’s submission, I can see no reason why Mr Denham could not participate in the expert conclave which has been delayed by the failure of both parties to comply with the case management orders.
I will also make some case management directions calculated to focus the attention of the parties for the status review before Chen J on 25 July 2025.
While I have not heard the parties on the issue and while the plaintiffs have succeeded on the motion, it seems tolerably clear in the circumstances that the dictates of justice require that the plaintiffs should pay the costs of and incidental to the notice of motion. I will make such an order but allow the parties seven days to indicate whether it seeks to contest that a different order relating to costs should be made.
For the foregoing reasons, I make the following orders:
The plaintiffs are granted leave to rely on the report of Marty Denham dated 30 June 2025 (“the report”) subject to the following conditions:
(i) The plaintiffs may not rely on the facts and opinions in part 10 of the report. (ii) The plaintiffs are to make an election to avoid relying on multiple experts on the same issue, and are not permitted to rely on the evidence of both Marty Denham and John Gardner to respond to the opinions of Colin Grantham stated in his report of 5 October 2023 at paragraphs [45], [46] and [47]. (iii) For the sake of clarity, if the plaintiffs elect to rely on the opinions of Marty Denham, the plaintiffs are not to rely on the opinions expressed by John Gardner in his report of 6 May 2025 on the same issue, that is the opinions stated in paragraphs [72]-[76] and [130]. (iv) Conditions (i)-(iii) do not prohibit the plaintiffs from relying on the evidence and opinions of John Gardner more generally.
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The reports are signed under the hand of “Dr” Grantham. Dr Grantham’s curriculum vitae indicates that he is also currently an Adjunct Associate Professor at the University of New South Wales. When asked at the hearing whether his correct title was “Mr”, “Dr” or “Professor”, counsel for the defendant replied: “I think it is all of the above, he is an associate professor”. See Tcpt (9/7/25) at p 25. For consistency, I will refer to him as Dr Grantham in this judgment.
See Tcpt (9/7/25) at p 25 and the affidavit of Mr King sworn 8 July 2025.
Paragraph numbering corrected.
Anthea Hammon
ASKO APPLIANCES
(2009) 239 CLR 175
(1997) 189 CLR 146