By Nick Triggle
BBC News health reporter
The partial smoking ban in England may open the floodgates for bar workers to sue their employers if they develop smoking-related illnesses, experts say.
England is due to get a partial smoke ban in 2007
The Health Bill presented to parliament last week bans smoking in workplaces because of the risk of passive smoking, but exempts certain pubs and bars.
Solicitors and campaigners warned smoking lawsuits could become as common as asbestos claims with a ban in force.
But the pub industry said it was not concerned at the moment.
A number of employees have already made claims against companies after becoming ill from second-hand smoke.
But no case has gone the full distance and set a legal precedent as most have been settled out-of-court.
One of the most famous cases was the casino worker Michael Dunn who reportedly received £50,000 after developing asthma. Under the terms of the settlement his employers did not accept liability.
Solicitors have said cases are hard to pursue as it has to be proved the illness was caused by being at work rather than exposure at home or in social situations.
But Ian Willmore, of anti-smoking group Action on Smoking and Health, said the proposed ban would give employees the impetus to go to court.
"The ban is being introduced because passive smoking causes harm. Employers can no longer say they were not aware of the risks.
"There will be a lot of cases."
John Hall, a disease specialist at Thompsons Solicitors, which represented Mr Dunn, said he would expect to see more claims in the future.
"It has been hard to prove in the past, but it just takes one case to set a precedent. That could happen and in 10 or 20 years it could be like asbestos claims."
More than 3,000 people die each year from asbestos-related diseases - a figure which is on the rise. Within 30 years it is estimated pay outs could top £20bn.
Mr Hall said passive smoking claims can be pursued under the Health and Safety at Work Act, which charges employers with a duty to protect their staff from avoidable risks.
Others believe human rights legislation may also be used.
The smoking ban which has been proposed prohibits smoking in all workplaces, except in private members clubs and non-food pubs.
It caused controversy when it was published last week, with the health lobby and many backbench Labour MPs saying the government should have gone further.
The Department of Health said it did not believe it would prompt more claims because measures would be taken to protect workers in smoking pubs.
And Mark Hastings, of the British Beer and Pub Association, said the industry was not concerned that there would be lawsuits.
"Pubs will conform to the law so why should they be at risk?"
However, he accepted that if a precedent was set the situation would change.