Two families have won groundbreaking claims to compensation after loved ones died from cancer following exposure to "low level" asbestos.
The Supreme Court ruled today in favour of the relatives of Dianne Willmore and Enid Costello, who both fell victim to malignant mesothelioma.
The ruling is expected to pave the way for similar claims from many other cancer sufferers exposed to "low levels" of asbestos.
Mrs Willmore, from North Wales, died in October 2009, aged 49, the day after a judge said she was entitled to £240,000 compensation.
The award, made against Knowsley Council for negligently exposing her to asbestos fibres, was frozen while appeals took place.
The mother-of-two contracted the cancer after apparently being exposed to asbestos dust while a pupil at Bowring School in Huyton, in the 1970s. She later moved to Wrexham.
Mrs Costello also fell victim to mesothelioma and died in January 2006, aged 74.
Her daughter, Karen Sienkiewicz, initially lost a county court claim to compensation, made on behalf of her late mother's estate, but won in the appeal court.
Mrs Costello was said to have breathed in dust containing asbestos when she was a secretary at a packaging factory in Ellesmere Port.
The compensation claim was against her former employer Greif (UK) Ltd.
The Court of Appeal ruled compensation should be paid in both cases, but Knowsley Council and Greif UK fought the rulings in the Supreme Court, the highest court in the land.
Today seven Supreme Court justices unanimously dismissed their appeals.
Knowsley and Greif had argued they could only be held liable if it could be proved they were responsible for causing exposure to asbestos that had at least "doubled the risk" of mesothelioma.
Rejecting the argument, the Supreme Court ruled there was no requirement for a claimant to show a doubling of risk.
Whether exposure was too insignificant to be taken into account was a matter for the trial judge on the facts of each particular case.
Later lawyers specialising in asbestos cases welcomed the ruling - handed down by Lord Phillips (Supreme Court president), Lord Rodger, Lady Hale, Lord Brown, Lord Mance, Lord Kerr and Lord Dyson.
Adrian Budgen, partner and head of Irwin Mitchell's national asbestos disease litigation team, said cases like Dianne Willmore's, involving schools and public buildings, "sadly are not uncommon".
Mr Budgen said: "This ruling is a positive step towards proper acknowledgement of the risks that asbestos can pose in schools and other public buildings, even if the amount of fibres which pupils, teachers and others come into contact with is relatively small.
"The risks posed by the toxic fibres have been shown to be far greater in children's lungs rather than those which are fully-developed, meaning school pupils are more susceptible to the dangers of asbestos.
"We hope that this ruling - and its implications over what 'low-level' exposure can lead to - will lead to a step change in how the hazardous material's presence in schools is viewed and hopefully lead to its eventual removal from all sites."
Ruth Davies, solicitor for Dianne Willmore's husband Barre, said her client was "absolutely delighted" with the ruling.
The case was particularly important as it was the first asbestos exposure case involving a pupil.
Ms Davies said Barre "knows how pleased Dianne was, knowing on her deathbed that her family would be provided for".
"He was relieved that she was unaware of this appeal. The compensation won't bring Dianne back but will provide some solace."
Ms Davies described the failed appeals as "another attack on asbestos disease victims. The defendants were trying to change the law that has been working perfectly well for many years so that fewer people who are dying can get properly compensated".
Norman Jones, solicitor for Enid Costello's family, said: "The dangers connected with asbestos exposure and the risks of mesothelioma have been known to employers since the early Sixties when the Sunday Times made public the hazards of being exposed to asbestos in the workplace.
"Employers were left in no doubt of the consequences of exposing their workforce to asbestos after reading this article.
"It would be manifestly unfair if the law had been changed to deny victims of one of the worst fatal industrial diseases from receiving fair compensation."
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