Hitchcock v Lake Macquarie City Council
[2021] NSWPICMP 16
•11 March 2021
| DETERMINATION OF APPEAL PANEL | |
| CITATION: | Hitchcock v Lake Macquarie City Council [2021] NSWPICMP 16 |
| APPELLANT: | John Hitchcock |
| RESPONDENT: | Lake Macquarie City Council |
| APPEAL PANEL: | Ms Catherine McDonald Dr Henley Harrison Dr Paul Niall |
| DATE OF DECISION: | 11 March 2021 |
| CATCHWORDS: | WORKERS COMPENSATION- Industrial deafness; worker had worked as a boilermaker for nearly 40 years; AMS said that the noise to which he was exposed was neither suitable nor sufficient to include the loss at low frequencies in the assessment – which is an error in the context of the history; Held- AMS made deduction for asymmetrical hearing loss which was less than would require investigation; MAC revoked. |
STATEMENT OF REASONS FOR DECISION OF THE APPEAL PANEL IN RELATION TO A MEDICAL DISPUTE
BACKGROUND TO THE APPLICATION TO APPEAL
On 30 November 2020 John Hitchcock lodged an Application to Appeal Against the Decision of Approved Medical Specialist. The medical dispute was assessed by Dr Sylvester Fernandes, as an Approved Medical Specialist (AMS) under the legislation in force at the date of the assessment, who issued a Medical Assessment Certificate (MAC) on 20 November 2020.
Mr Hitchcock relies on the following grounds of appeal under s 327(3) of the Workplace Injury Management and Workers Compensation Act 1998 (1998 Act):
· the assessment was made on the basis of incorrect criteria,
· the MAC contains a demonstrable error.
The Registrar was satisfied that, on the face of the application, at least one ground of appeal has been made out, being that the AMS made a demonstrable error. The Appeal Panel has conducted a review of the original medical assessment but limited to the ground of appeal on which the appeal is made.
The Workers Compensation Medical Dispute Assessment Guidelines set out the practice and procedure in relation to the medical appeal process under s 328 of the 1998 Act. An Appeal Panel determines its own procedures in accordance with those guidelines.
The assessment of permanent impairment is conducted in accordance with the NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed 1 April 2016 (the Guidelines) and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5th ed (AMA 5).
This is a majority decision of the Appeal Panel.
RELEVANT FACTUAL BACKGROUND
Mr Hitchcock has been employed by Lake Macquarie Council (the Council) as a boilermaker since about 2007. He has worked as a boilermaker for about 38 years. The Council does not dispute that it employs Mr Hitchcock in noisy employment. The Council referred Mr Hitchcock for audiometric monitoring under the supervision of Dr B Raffan over the course of his employment and in 2016 Dr Raffan gave Mr Hitchcock copies of his audiograms and recommended that he seek legal advice about a claim and medical advice about management of his condition.
Mr Hitchcock made a claim for permanent impairment compensation and for the cost of hearing aids on 9 May 2020, supported by a report of Dr P Dhasmana dated 11 February 2020. Dr Dhasmana undertook an audiogram which showed that Mr Hitchcock had bilateral high frequency sensorineural hearing loss and which he considered was consistent with a diagnosis of industrial deafness. Dr Dhasmana assessed 23.4% hearing loss. Though he did not mention the issue in his report, his audiogram shows that he included the results at all frequencies from 500 Hz to 4,000 Hz in that assessment. He included a loading of 3% for severe tinnitus and deduced 0.4% for presbycusis, resulting in an assessment of 26% binaural hearing loss or 13% whole person impairment (WPI). Dr Dhasmana considered that Mr Hitchcock required hearing aids as a result of that loss.
The Council referred Mr Hitchcock to Dr K Howison who reported on 15 July 2020. Dr Howison said that he considered the cumulative noise emission levels to which Mr Hitchcock had been exposed and said that all frequencies have been damaged by unacceptable noise levels so that he used the results of all levels in his assessment. Dr Howison assessed 17.5% binaural hearing impairment. He deducted 0.6% for presbycusis (Mr Hitchcock having had a birthday since Dr Dhasmana’s assessment) and allowed 3% for severe tinnitus resulting in 19.9% binaural hearing loss or 10% permanent impairment. Dr Howison also recommended hearing aids.
The MAC is discussed in detail below. The AMS said that Mr Hitchcock suffered asymmetric hearing loss and equated the noise-induced component of the greater loss in the right ear with that in the left. He said that the history of noise exposure was not sufficient to include the losses below 1500Hz in his assessment.
The AMS said that Mr Hitchcock suffered non-occupational hearing loss in the lower frequencies, age-related hearing loss (presbycusis) and additional loss on the right side.
The AMS assessed 18.6% binaural hearing loss and deducted 0.6% for presbycusis. He allowed 2% for severe tinnitus, resulting in a final assessment of 16.9% binaural hearing loss or 9% WPI.
PRELIMINARY REVIEW
The Appeal Panel conducted a preliminary review of the original medical assessment in the absence of the parties and in accordance with the Workers compensation medical dispute assessment guidelines.
As a result of that preliminary review, the Appeal Panel determined that it was not necessary for the worker to undergo a further medical examination because Mr Hitchcock did not argue that the audiogram relied on was inadequate and there is sufficient information in the file to determine the appeal.
EVIDENCE
The Appeal Panel has before it all the documents that were sent to the AMS for the original medical assessment and has taken them into account in making this determination.
The parts of the medical certificate given by the AMS that are relevant to the appeal are set out, where relevant, in the body of this decision.
SUBMISSIONS
Both parties made written submissions. They are not repeated in full, but have been considered by the Appeal Panel.
In summary, Mr Hitchcock, through his solicitor Mr Dougall, submitted that the AMS took an inadequate or incomplete history of the noise to which he was exposed at work, which was a demonstrable error. He said that the AMS relied on a chart recording his employment recording details of a range of factors which are not set out in the Guidelines, suggesting that the AMS relied on his own methodology.
Mr Hitchcock submitted that the AMS applied incorrect criteria in failing to include the frequencies below 1.5Hz in his assessment and with respect to the application of s 323 of the 1998 Act. He said that the AMS appeared to assume that hearing loss must be proved to be work related before it can be included in the assessment and submitted that “if hearing loss is only ‘possibly’ work related if should, on the balance of probabilities be accepted as work related.”
In reply, the Council submitted that Mr Hitchcock had not shown how the history taking by the AMS was inadequate or how a more detailed history would have led to a different outcome. It said that the AMS performed a proper assessment and took a thorough history.
The Council cited examples of Appeal Panel decisions which considered whether loss in the lower frequencies should be included in the assessment of noise-induced hearing loss and said that the inclusion of those frequencies depended on the facts of the individual case. It submitted that in this case the flat line profile of the audiogram was inconsistent with noise induced hearing loss and the AMS provided his reasons for not including those frequencies. The Council submitted that the AMS was not required to adopt the conclusions of the independent medical examiners qualified for the parties.
With respect to s323, the Council submitted that it was reasonable and sufficient for the AMS to adopt a one-tenth deduction.
The Appeal Panel notes that the AMS did not make a one-tenth deduction.
FINDINGS AND REASONS
The procedures on appeal are contained in s 328 of the 1998 Act. The appeal is to be by way of review of the original medical assessment but the review is limited to the grounds of appeal on which the appeal is made
In Campbelltown City Council v Vegan[1] the Court of Appeal held that the Appeal Panel is obliged to give reasons. Where there are disputes of fact it may be necessary to refer to evidence or other material on which findings are based, but the extent to which this is necessary will vary from case to case. Where more than one conclusion is open, it will be necessary to explain why one conclusion is preferred. On the other hand, the reasons need not be extensive or provide a detailed explanation of the criteria applied by the medical professionals in reaching a professional judgement.
[1] [2006] NSWCA 284.
The MAC
It must be said that the language and the style of the MAC make it difficult to follow. The formatting of some of the quotes, which appear below, has been altered to be consistent with this decision.
Though the AMS did not set out a detailed history, he accepted that the noise to which Mr Hitchcock has been exposed was the cause of noise induced hearing loss:
“Source of hazardous steady- state, fluctuating, intermittent and impact noise at such employment (i.e. on balance of probabilities these employments have the necessary ‘incidents, tendencies and characteristics’ so as to give rise to a real risk of a person suffering noise induced hearing loss there from): trucks, grinding, hammering”
The AMS tabulated Mr Hitchcock’s history of noise exposure, noting the duration, the hours worked per week, whether it was noisy (in terms of whether employees one metre apart have to shout to be heard), whether the noise was continuous or impact noise, the working distance from the source of the noise and whether hearing protection was required. We do not agree with Mr Hitchcock’s submission that the factors relied on are inconsistent with the Guidelines.
The AMS undertook an examination and set out his findings and summarised the results of an audiogram. He said:
“Audiogram on 18/11/2020
Testing: He responded well to the subjective aspects of the audiogram carried out in accordance with the Workcover Guides Chap 9.8 p 43. An accurate hearing test was achieved, for there was very good intratest reliability.”The AMS summarised the injuries and diagnoses in the following way:
“(Key: bass: <1 KHz; midrange: 1 – 2 KHz; treble: > 2 KHz)
1. Noise induced hearing loss in the upper middle and treble frequencies and
2. an excess loss of uncertain origin (non occupational*) in the bass and lower middle
frequencies and
3. age related hearing loss and
4. an additional excess loss of unknown origin (non noise induced) on the right side.*There are many possible causes of non-occupational hearing loss. The validity of the finding of a nonoccupational contribution to a hearing loss is not conditional on the identification of the medical aetiology thereof, be that identification precise or otherwise. Nor is it necessarily clinically difficult to assess that a component or all of a hearing loss (including where it may be of uncertain medical aetiology or deafness due to an unknown cause or causes) is non-occupational. This depends on the circumstances of the particular case.
Also, in hearing loss cases the deduction is not for pre-existing conditions, but it is for hearing loss not due to noisy employment. It can usually be calculated exactly and the 10% deduction used in other compensation claims is not often needed. Thus, in this case, there is no necessity to explain the cause of the low tone hearing.”
The AMS gave reasons for his assessment:
“Mr. Hitchcock has an asymmetric hearing loss, with the right side being worse than the left side.
Noise induced hearing loss is essentially symmetric, as in most occupational environments, the ears are exposed to similar sound levels bilaterally, even when the apparent noise source comes from one side.
In the instant case, the right ear is hence equated to the left. As a result, the hearing loss on the left side has been taken into consideration for the calculation of noise induced hearing loss on the right side. He has been instructed to seek further attention for the elucidation of the causative element in the excess hearing loss which is not noise induced. (See also Dobie RA, Does Occupational Noise Cause Asymmetric Hearing Loss? Ear Hear 2014 Sep-Oct; 35(5):577; See also Pereira v Siemens Limited [2016] NSWWCCMA 9 (Pereira) and The UGL Rail Services Pty Ltd v Attard [2016] NSWSC 911.)”
Neither of the cases to which the AMS referred deal with asymmetric hearing loss.
The AMS said:
“The frequencies below 1.5 KHz are not included in the calculation because:
1. The historical noise exposure is not ‘suitable or sufficient’ to cause a noise induced hearing loss at these frequencies because the cumulative immission levels are not high
enough to involve these frequenciesHence after consideration of the nature and duration (immission levels) of occupational noise exposure and the nature and extent of all the hearing losses, including those at 0.5, 1 and 1.5 KHz, the hearing losses at 1.5, 2, 3 and 4 KHz are caused by his occupational noise exposure.
Shone v Country Energy (2007) NSW WCC MA 18 is perennially implored as authority for inclusion of the lower frequencies, in an effort to ascribe to Shone a ‘regulatory science’ status. It is important to understand that it is not possible to impart the ‘bright-line’ of certainty of law to an essentially fluid subject (that is a function of several
variables) requiring a clinical judgement (See also ‘Richardson’ [2013] NSW WCC MA 56) and fundamentally requires each case to be judged on its merits.In making that assessment I have taken account of the following matters:-
1.Type and duration of noise exposure (immission levels)
2.Type of hearing impairment
3.Mode of onset and progression
4.Shape of audiogram
5.Presence of a dip or ‘bulge’ around 4 kHz
6.Clinical picture
7.No competing diagnoses and complications”
The AMS said that Dr Dhasmana obtained asymmetric loss but “did not provide cogent reasons for not considering the same in his calculations of WPI.” He said:
“Dr K . Howison pretermits the asymmetric hearing loss that he obtained by quoting on p 7 of his report, ‘… as recommended by AAO-HNS (Otolaryngol Head and Neck Surg. 1995; 113: 179-180.’
This ad vericundium (appeal to authority) statement is essentially not in context here and if this is the reason provided for not equating then it is worth noting that the recommendation by this body is basically for the medical investigation of retrocochlear pathology and has no application in medicolegal cases of noise induced hearing loss. In other words, Dr. Howison is employing the statement noncontextually for a medicolegal purpose. Noise induced hearing loss being essentially symmetric, only an interaural difference of upto ± 5dB is acceptable within the bounds of behavioural threshold audiometry unless the circumstances of noise exposure vary situationally on the both sides . Also, Dr. K. Howison infers by this statement that if the pathology is not retrocochlear (implying an ‘acoustic neuroma’ tumour), than it must be a noise induced hearing loss, thus ignoring the possibility of all other non noise induced pathologies in the cochlea and the acoustic nerve.
These observations are mentioned for the benefit of the instructing parties. They have no impact on my assessment”.
With respect to the deduction under s 323 of the 1998 Act, the AMS said that Mr Hitchcock suffered from pre-existing abnormalities:
“1. an excess loss of uncertain origin (non occupational) in the lower frequencies and
2. age related hearing loss and
3. an additional excess loss of unknown origin (non noise induced) on the right side”
He explained that he did not make a deduction of one-tenth because:
“In hearing loss cases the deduction is not for pre-existing conditions, but it is for hearing loss not due to noisy employment. It can usually be calculated exactly and the 10% deduction used in other compensation claims is not often needed.”
That statement is incorrect. Section 323 of the 1998 Act applies only to previous injury or a pre-existing condition or abnormality. There is no exception in the legislation for hearing loss cases.
Presbycusis is not deducted under s 323 but because the Guidelines prescribe that the National Acoustic Laboratories Report No 118 January 1988 Improved Procedure for Determining Percentage Loss of Hearing, including the Presbycusis Correction Table is to be used[2]. Similarly, the Guidelines provide[3] that the AMS is to assess the non-work related component and record any deduction in the report.
Use of the lower frequencies
[2] Paragraphs 9.5, 9.9 and 9.10.
[3] Paragraph 9.4.
Noise-induced hearing loss was described in the Workers Compensation Act 1926 as “ ‘boilermakers deafness’ and any deafness of like origin”[4], acknowledging that boilermaking work is archetypically noisy.
[4] Section 7(4B).
There are a number of Appeal Panel decisions in which losses at the lower frequencies have been included in an assessment of hearing loss. Each Appeal Panel decision turns on its own facts and is not a precedent to be followed. They are examples of the application of relevant principles to the facts of the case.
Mr Hitchcock told the AMS that he had been exposed to loud industrial noise over the whole of his working life as a boilermaker. The AMS accepted that the noise was sufficient to cause hearing loss but he said that the noise was fluctuating and intermittent which is at odds with the evidence and suggests that the AMS has not properly considered the evidence.
The AMS noted the typical noise levels from grinders and hammering but that information does not match Mr Hitchcock’s own evidence. There is no evidence in the file measuring the noise levels to which Mr Hitchcock was exposed – but there is a concession that the work was noisy employment.
However, the AMS said that Mr Hitchcock’s historical noise exposure was not suitable or sufficient to cause noise induced hearing loss at the low frequencies because the cumulative immission levels – the amount of noise coming in to his ear – is insufficient. The AMS did not provide reasons for that opinion, though his assumption that the noise was intermittent may explain why he formed that view. It was an error for the AMS to say that the noise of boilermaking was not “suitable” to cause noise induced hearing loss at the low frequencies.
Mr Hitchcock commenced his apprenticeship as a boiler maker when he was 16 years old. At the date of his examination by the AMS, he had worked in the industry for more than 40 years. He said in his statement:
“This type of work is noisy and there is exposure to noise not only from the environment in which we work but also from specific plant and equipment, including grinders, saws and whilst welding. It is noisy work with a of banging and clanging of metal.”
If, in the context of the work Mr Hitchcock performed, the AMS considered that those immission levels were insufficient to cause noise induced hearing loss at the lower frequencies, he was required to explain why, rather than merely stating that they were not. His suggestion on page 4 that it is not necessary to explain the cause of the low tone loss constitutes a failure to give reasons for his opinion. Whilst it may not generally be necessary to provide a diagnosis for non-work related hearing loss, it was appropriate to provide an explanation why the loss at low frequencies was not included in the case of a worker who had spent almost 40 years as a boilermaker.
There is no evidentiary basis for the AMS’s statement that the cumulative immission levels at the lower frequencies were insufficient to cause noise induced hearing loss. While some of the noise is intermittent – such as hammering – and the noise is fluctuating, the kind of work which Mr Hitchcock undertook exposed him to almost constantly present loud noise. Based on the length of time Mr Hitchcock has worked as a boilermaker and the noise to which he was exposed, it was an error for the AMS not to include the lower frequencies in his assessment.
Section 323 deduction
The AMS made a deduction under s 323 of the 1998 Act in respect of asymmetrical loss because the loss in the right ear was greater than the left at 2000, 3000 and 4000 Hz.
The audiograms undertaken by Drs Dhasmana and Howison also show that asymmetry. Dr Dhasmana did not comment on it and did not make any deduction from his assessment in respect of it.
Dr Howison said that the difference was not symmetrical but the asymmetry was small and less than would require investigation.
While noise induced hearing loss is generally symmetrical, the results obtained by the AMS are within the range of test results that would not require a deduction for asymmetry. On another test, the asymmetry may not appear.
There is no medical reason in Mr Hitchcock’s history to explain the asymmetry.
The cases to which the AMS referred in the paragraph about asymmetric hearing loss are not relevant to the question of whether it should be excluded.
It would have been appropriate to include all of the losses in the assessment of hearing loss despite the asymmetry and the AMS was in error in failing to do so.
However, even when all of the hearing loss assessed is included, Mr Hitchcock’s hearing loss falls below the threshold for compensation.
For these reasons, the Appeal Panel has determined that the MAC issued on 20 November 2020 should be revoked, and a new MAC should be issued. The new certificate is attached to this statement of reasons.
APPEAL PANEL
MEDICAL ASSESSMENT CERTIFICATE
Injuries received after 1 January 2002
This Certificate is issued pursuant to s 328(5) of the Workplace Injury Management and Workers Compensation Act 1998.
The Appeal Panel revokes the Medical Assessment Certificate of Dr S Fernandes and issues this new Medical Assessment Certificate as to the matters set out in the Table below:
Table - calculation of whole person impairment (WPI) for industrial deafness as set out in the Table immediately below in accordance with Chapter 9 of the Guidelines for the Evaluation of Permanent Impairment and 1988 NAL Tables:-
| Notional date of injury | Frequency Hz | Left dB HL Air Bone | Right dB HL Air Bone | Total % BHI | Occupational % BHI |
| 8 June 2020 | 500 | 15 15 | 20 20 | 0.4 | 0.4 |
| 1000 | 20 20 | 20 20 | 0.8 | 0.8 | |
| 1500 | 20 20 | 20 20 | 0.6 | 0.6 | |
| 2000 | 25 25 | 45 45 | 2.5 | 2.5 | |
| 3000 | 60 55 | 70 65 | 6.5 | 6.3 | |
| 4000 | 70 70 | 85 70+ | 7.8 | 7.8 | |
| 18.6% | |||||
| TOTAL % BHI: 18.6% | |||||
| Less Pre-existing non-related loss: 0% | |||||
| Less Presbyacusis correction: (0.6%) 18% | |||||
| Add % of severe tinnitus: (2%) 20% | |||||
| Adjusted total % BHI: 20.0% | |||||
| Resultant total BHI of 20.0 % = 10 % whole person impairment (Table 9.1) | |||||
The above assessment is made in accordance with the Guidelines for the Evaluation of Permanent Impairment for injuries received after 1 January 2002
Catherine McDonald
Arbitrator
Dr Henley Harrison
Approved Medical Specialist
Dr Paul Niall
Approved Medical Specialist
11 March 2021
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