29 June, 2020
Claims brought as a result of a claimant developing mesothelioma are often brought many years after the alleged exposure to asbestos due to the long latency period of the disease. It can be anything from 10 years to several decades after exposure before symptoms manifest themselves. As a result, they are fraught with difficulties for both claimants and defendants.
One defence that can often be successfully deployed is that there was limited exposure, such that the legal requirements for establishing liability are not met.
In a mesothelioma case, the claimant has to prove, on the balance of probabilities, that the defendant owed a duty of care not to expose him to asbestos dust and the consequent risk of asbestos-related injury; that the defendant had breached that duty; that the breach caused a material increase in his risk of developing mesothelioma; and that he had suffered loss and damage as a result. ,A "material" increase in risk is one that is not so insignificant as to be disregarded as de minimis, and whether an increase was de minimis is a matter for the judge to determine on the facts.
In the recent case of Valerie Bannister (Executrix of the Estate of Dennis Charles Bannister, Deceased) v Freeemans  EWHC 1256 (QB) the High Court has given some general Obiter views on what constitutes a material increase in the risk of a claimant developing mesothelioma.
Mrs Bannister sought to establish that her husband died of malignant mesothelioma as a result of being negligently exposed to asbestos dust when his workplace was refurbished some 35 years previously whilst employed by the Defendant.
Mr Bannister died in 2019. He had been employed in the defendant's accounts department and did not work with asbestos. However, Mrs Bannister, on behalf of her husband, alleged that in the mid-1980s, the offices in which he worked were refurbished and, over the course of a weekend, partitions containing asbestos were removed and replaced. She claimed that when the deceased returned to work the following Monday, he was exposed to asbestos dust which had been left on his desk and on the floor and was not cleaned up for a few days.
The defendant accepted that they owed a duty to the deceased to reduce exposure to asbestos to the lowest level reasonably practicable and that it would have been in breach of that duty had there been visible residues of asbestos dust in the office after the works, the deceased alleged.
However, they denied that the deceased had been exposed to asbestos dust while in its employment. They also contended that asbestos is founds in the lungs of every adult, largely as a consequence of the past presence of asbestos in buildings, vehicles and in commerce.
In considering whether there had been exposure to asbestos dust the court found that there were inconsistencies in the claimant's evidence and in that of his witness, that there was no documentary evidence to either support or undermine the claimant's evidence as to exposure. The Court concluded that it was probable that works which produced asbestos dust were carried out at the material time. However, the claimant had not established, on the balance of probabilities, that the deceased had been exposed to such dust. Knowing that the office partitions contained asbestos, the defendant would probably have engaged reputable, specialist contractors who would have been aware of the risks and would not have allowed asbestos dust to remain in the offices. So his claim failed.
However, it is the obiter comments on what constitutes a "material increase" of developing mesothelioma that are a helpful reminder of the principles.
The Judge said that
Cases such as this are fact specific, and the judge has to decide if exposure has been sufficient to attract liability on a case by case basis.
There is no specific minimum dose that can be relied upon to establish a de minimus defence.
We understand that the Claimant is seeking to appeal this judgment.