Workers will be able to sue employers who fail to create a smoke-free environment. Environmental health inspectors will also have the power to prosecute them.
But prisons, psychiatric hospitals, pubs and clubs, where smoking is regarded as part of the culture, will be exempt, under the Government's White Paper on Smoking and Health, to be published next month.
The proposals also permit smoking in outdoor workplaces, such as farms and construction sites.
Sources close to the Department of Health say that smoking at work is a key target in the government drive to reduce tobacco-related deaths.
But Tessa Jowell, the Minister for Public Health, is sensitive to accusations of nannying, and has stopped short of banning smoking altogether throughout office buildings. Employers would be allowed designate special rooms and places such as stairwells for smokers to use.
She also plans to put the proposals out to consultation, to enable businesses and smokers to comment.
The White Paper will propose segregating smoking and non-smoking areas in pubs and clubs and installing ventilation systems. It will also suggest free Nicorette gum and patches free for the poorest in society.
At the moment Health and Safety codes of practice on smoking at work are vague. They say: "effective and suitable provision should be made to ensure that every enclosed workplace is ventilated by a sufficient quantity of fresh or purified air."
The revised codes would explicitly ban cigarette smoking where people work in enclosed places.
"Enforced passive smoking is a real invasion of civil liberties. Making non-smokers spend their working day in smoke-filled rooms is completely unfair," said Clive Bates, Director of Action on Smoking and Health, which has been lobbying for change for 25 years. "If it's true that the Government plans to stop smoking in the workplace, it's great news."
As well as clamping down on passive smoking, the White Paper will lay out plans for advertising and sponsorship bans, ways of preventing young people from starting smoking and helping addicts to stop.
Publication of the White Paper has been delayed until the beginning of December because of the sensitivity of its contents.Reuse content