This month has seen another de minimis success for insurers in the case of Harbison.[i]
The 63 year old claimant was employed by the defendant over 29 years between 1975 and 2006 as a production operative in a car plant and alleged NIHL from exposure to excessive noise. The issues in this case were:
The defendant admitted breach of duty and accepted the claimant’s evidence without cross-examination. There was no oral evidence given at the trial which was allocated to the fast-track. The defendant had no medical expert evidence to rely upon. The medical evidence was restricted to the written evidence of the claimant’s expert only, Mr Sharma.
The claimant underwent two audiograms for the purposes of the claim. The first was carried out on 10 May, 2014 as part of Mr Sharma’s medical report who diagnosed NIHL with a bilateral qualifying notch at 4kHz using the ‘CLB Guidelines’ 2000.
Following a request by the defendant, another audiogram was carried out on 24 September, 2015. However, at the time of that test, the claimant’s left ear was occluded with wax and so the left ear results from that test were deemed unreliable. In the right ear the 4 kHz notch found in the 2014 audiogram had disappeared and the hearing threshold improved from 40dB to 20dB. To continue supporting a diagnosis of NIHL Mr Sharma now relied upon a bulge of 8.6dB at 6 kHz. This fell short of the threshold of 10dB required to meet the R3a requirement in the CLB Guidelines. However, when he looked at the results for the right ear from the two audiograms he found that the bulge at 6 kHz averaged 12 dB and so was sufficient to meet the reduced threshold requirement of 7dB when averaging (see section 7.5 of the CLB Guidelines) and so maintained his diagnosis of NIHL. He also used the averaged results of both audiograms of the right ear over 1, 2 and 3 kHz to find an additional binaural hearing loss due to noise of 1dB over those frequencies.
The defendant submitted that averaging of the audiograms was inappropriate as the hearing thresholds between the two differed by 20dB which was significantly more than the margin of acceptable audiometric variability of 10dB. The later 2015 audiogram demonstrated a significant improvement in thresholds which was not consistent with NIHL.
However, HHJ Carmel Wall stated:
‘In considering the strength of this argument I have regard to the fact that Mr Sharma was not challenged as to the appropriateness of averaging the two audiogram results; and that he had justified this method by reference to the CLB guidelines. His approach was thus a recognised mainstream approach to multiple audiograms designed to improve reliability of outcome. In those circumstances I conclude that I should be slow to reject his approach where there is no expert evidence to suggest that he was wrong to take that approach in this case’.
The judge found that when averaging the results at 6 kHz this satisfied the CLB requirement and so the claimant had proved the diagnosis of NIHL. We discuss the topic of averaging multiple audiograms in greater detail in our feature article below.
De Minimis?
The judge then turned to consider whether or not the NIHL was compensable. Based on averaging the two audiograms, when measured across 1, 2 and 3 kHz the claimant’s NIHL was 1dB. Mr Sharma’s opinion was that when looking across these frequencies there would generally be no noticeable subjective effect or material disability from that level of NIHL. The judge concluded that when the claimant’s hearing was considered across 1, 2 and 3 kHz, he was not ‘appreciably worse off’ due to NIHL.
In relation to the loss at 4kHz on the first audiogram, which showed that that the claimant had a measured additional hearing loss after age adjustment of 19dB in his right ear and 29dB in his left, the claimant argued that Mr Sharma’s responses to the Part 35 questions supported the inference that the claimant was appreciably worse off as a consequence of this loss. However, the judge rejected this and accepted the defendant’s argument that Mr Sharma had suggested the possibility that hearing loss at high frequency could be subjectively noticeable or have a material effect but that that this fell short of discharging the claimant’s burden of showing that he was appreciably worse off as a consequence.
As such it was concluded that:
‘[…] on the evidence before me the claimant does have mild hearing impairment. However he has not discharged the burden of showing that on the balance of probabilities the NIHL hearing loss that is additional to the effect of age has made him appreciably worse off. I am not satisfied the injury caused by NIHL is compensable.
The outcome in this case differs from another 1st instance decision of Briggs v RHM Frozen Food Limited,[ii] where there was again little or no NIHL at 1-3 kHz but a loss of up to 15dB at 4 kHz. That loss was found to be compensable. So why the different outcome to Harbison? In Briggs one of the factors that told in favour of compensation was the claimant’s accelerated need for hearing aids-an issue not advanced in Harbison. Additionally, in Harbison the judge indicated that in order to prove that loss at 4kHz had caused the claimant some disability, the audiogram alone would not be enough and that the claimant and his expert had failed to adduce any evidence that the claimant was ‘appreciably worse off’ as result of such loss - a failing on the claimant’s part not to provide written or oral evidence to this effect.
The raft of 1st instance NIHL judgements on de minimis seen over the last few years are very fact-specific, but outcomes often seem determined on the absence of evidence presented by either of the parties. As we have previously cautioned do not run cases without your own expert evidence.
Further details about previous de minimis decisions and how to run a successful de minimis defence can be found in edition 133 of BC Disease News here.