Michael Dunn's employers have not accepted liability

Michael Dunn was reportedly paid up to �50,000 in an out of court settlement by Napoleon's Casino in Leicester Square, central London, where he worked as an inspector for 14 years.

Mr Dunn, who does not smoke and was a marathon runner until he developed asthma, said that constantly breathing in cigarette and cigar smoke on the gaming floor led to him getting the condition.

After a three-and-a-half year legal battle, backed by the GMB Union, Mr Dunn has settled out of court with the casino owners agreeing to pay him a five figure sum.

I think it will certainly push forward the strength of the campaign for ultimately smoke-free legislation Amanda Sandford from ASH

The payout comes with the conditions that he is not allowed to speak about the case and his employers have not accepted liability.

Amanda Sandford, from the anti-smoking group Action on Smoking and Health (ASH), told BBC London this case could set a precedent.

"I think it will certainly push forward the strength of the campaign for ultimately smoke-free legislation," she said.

"But in the short-term I think that we'll see far more of these cases where people have been harmed by the effects of passive smoking will be seeking compensation."

A second case is already under way against Napoleon's Casino.