Mackenzie v Alcoa Manufacturing (GB) Ltd

An employer’s duty to investigate workplace noise does not arise automatically upon publication of guidance. A reasonable period must be allowed for the employer to understand the guidance, obtain specialist advice and act upon it. On the evidence, that duty arose in 1970. Where a defendant’s breach of that duty makes proof of noise exposure difficult, the court should assess the claimant’s evidence benevolently and the defendant’s evidence critically. Expert evidence explaining why historic exposure cannot now be established does not make the absence of surveys irrelevant. A trial judge must also address a material legal submission and give reasons for accepting or rejecting it.

The claimant brought a claim for noise-induced hearing loss arising from work at the respondent’s aluminium-processing factory between approximately 1963 and 1976. The County Court dismissed the claim, finding that the claimant had not proved tortious exposure to excessive noise. The claimant appealed on grounds concerning the respondent’s failure to produce noise surveys, the approach required where that failure impeded proof, and the applicable noise threshold for a peripatetic worker from 1972 onwards.

The appeal also challenged the trial judge’s failure to address expressly the claimant’s submission concerning exposure at or above 90 dB(A). The High Court considered when the duty to conduct surveys arose, the evidential consequences of failing to conduct or produce them, and whether the matter should be remitted.

1. The appeal was allowed on Grounds 1–4. The issue raised by Ground 5 was not determined because the conclusions on Grounds 1–3 were sufficient to dispose of the appeal.

2. The court held that the guidance published in 1963 did not establish a duty to conduct a noise assessment during the period immediately following publication, because the claimant could not show that several of the listed indicators of a noise problem were present. The 1968 edition changed the position. A reasonable period was required for an employer to understand the guidance, obtain specialist advice and act on it. Applying the approach recognised in Baker v Quantum Clothing Group Ltd [2011] UKSC 17, the operative duty to conduct noise surveys arose from 1970.

3. The trial judge was wrong to distinguish Keefe v The Isle of Man Steam Packet Company Ltd [2010] EWCA Civ 683. Where the defendant should have obtained noise surveys but produced none, and gave no evidence explaining their absence, it could not rely on the present inability to establish that exposure was excessive. The claimant’s evidence should be judged benevolently and the defendant’s evidence critically. The expert evidence did not provide positive evidence of the claimant’s actual exposure; it instead demonstrated why the historic exposure could not now be established, which reinforced the significance of the missing surveys.

4. The claimant’s evidence, read benevolently, supported exposure to tortiously high noise levels. The trial judge therefore ought to have reached that conclusion rather than accepting the expert evidence as determinative.

5. The trial judge also failed to address a discrete and material submission concerning the distinction between an average daily noise dose and exposure at or above 90 dB(A). In accordance with English v Emery Reimbold [2002] EWCA Civ 605, the judge was required to explain why that submission was rejected or why the respondent’s case was preferred.

6. The case was remitted to the County Court for assessment of damages.

• High Court (Queen’s Bench Division): Appeal from the County Court allowed on Grounds 1–4. The case was remitted to the County Court for assessment of damages.
• County Court at Swansea: The claim against both defendants was dismissed on 15 November 2017.