High court reiterates burden of proof on claimant to prove negligent exposure to asbestos, and clarifies meaning of “substantial dust” as set out in Factories Acts.

The case

The deceased was exposed to asbestos while working in the defendant’s joinery workshop manufacturing fire doors from 1973 to 1977. As a result of his occupational exposure to asbestos he developed mesothelioma and died in August 2015, aged 60.

It was alleged that the exposure was negligent and in breach of the Asbestos Regulations 1969 and section 63 of the Factories Act 1961.

The defendant’s witnesses (including the joinery shop manager) could not recall asbestos being used in the manufacture of any item in the joinery shop.  At the relevant time two types of fire door were produced, half hour fire doors containing no asbestos and one hour fire doors containing an asbestos sheet underneath the plywood facing. The defendant’s witnesses could not exclude the possibility that one hour fire doors were made occasionally within the joinery shop.

The dispute hinged on whether exposure limits set out in the 1970 Factory Inspectorate Technical Data Note (TDN13) had been exceeded, and whether the amount of dust given off by the process was “substantial” within the definition set out in section 63 of the 1961 Act.

The decision

The court considered previous decisions including Williams v University of Birmingham [2011] EWCA Civ 1242 and Robert Prescott v. University of St Andrews [2016] CSOH 3. These authorities held that in order to succeed in establishing common law negligence a claimant must establish, on the balance of probabilities, the actual level of asbestos dust to which he was exposed.

Although the court found that the deceased did occasionally make the fire door containing asbestos, there was no breach of the common law duty of care. The risk of mesothelioma was known when TDN13 was published and notwithstanding the risk, those exposure limits were set by the HSE.  A responsible and reasonable employer would interpret TDN13 to mean that exposure below those limits was an acceptable risk.  There was an extraction system in place in the defendant’s premises and the deceased only occasionally manufactured the fire door containing asbestos. Any exposure would, on balance, have been below the TDN13 limits.

Section 63 of the 1961 Act sets out that:-

“In every factory in which… there is given off any dust…as to be likely to be injurious or offensive to the persons employed, or any substantial quantity of dust of any kind, all practicable measures shall be taken to protect the persons employed against inhalation of the dust or fume or other impurity and to prevent its accumulation in any workroom….”

The Court held that there was no breach of statutory duty.  It was not foreseeable, in terms of the common law, that the level of asbestos dust to which the deceased was exposed would have been injurious. “Substantial” is more than “not negligible”, and there was no evidence that such quantities of dust had been given off as a result of the process involved.

Points for defendants

This is an important judgment for asbestos litigators, further developing the case law on negligent exposure levels and the standard of evidence required to prove that negligent exposure took place. 
The case reinforces the Court of Appeal’s decision in Williams v University of Birmingham and the recent Scottish decision of Prescott v University of St Andrews
The judge recognised that:

“[T]his will be an unwelcome and difficult decision for the Claimant…. Where any exposure many years ago to asbestos fibres may be established, the law does not require the defendant company to prove that it was not reasonably foreseeable that such an exposure level was likely to cause asbestos-related injury: it is for the Claimant to prove both that the defendant company was negligent, and that its breach of duty caused a material increase in the risk that the victim would develop mesothelioma. That is a particularly difficult burden of proof to discharge, where the case for the Claimant is handicapped by the passage of time and such evidence as is available cannot clearly demonstrate failure to conform with the requirements of TDN13.”

The case also provides helpful clarification on the interpretation of “substantial dust”.  It is clear from this decision that intermittent, occasional, low level dust exposure will not be sufficient to establish breach in terms of the Factories Acts.