The revelation comes from research into a problem linked to sickness which affects more than half a million British workers.
The executive, which last week began a crackdown on employers who unnecessarily subject their workers to stress, has employed research teams at three universities to investigate the issue. They have found that modern practices designed to create a more pleasant and efficient working environment are compounding stress levels.
The executive's director-general Jenny Bacon said: "One of the things that is coming through is that less-conventional modes of employment like part-time work, working from home and multiple contract employment are all pretty stressful situations.
"If you have got people working from home, communication becomes much more difficult and the workers suffer from increased vulnerability."
She said the introduction of noisier open-plan offices and greater use of team-working had also led to increased tension. "If you are suddenly putting people who are used to being autocrats into positions where they are a team player, they are likely to be stressed."
Last week Unison, the public service union, complained that modern "hot- desking" practices, designed to encourage flexibility by moving employees from one available work-station to another, were causing stress.
Staff in call centres, where workers field telephone enquiries from customers, said they had no personal space in the office. "The technology may be state of the art but you feel like a slave," said one.
The executive is considering a code of practice on stress, giving it stronger legal backing to force employers to accept changes or face prosecution.
A code, which the Confederation of British Industry regards as unnecessary and out of proportion to the scale of the problem, would require the backing of health and safety commissioners and Deputy Prime Minister John Prescott.
Health and safety inspectors are on the look-out for evidence of extreme stress, and firms could be prosecuted for cases in which employees are so stressed they become ill.
But firms are more likely to be served with improvement notices under the Health and Safety at Work Act, and will be prosecuted if they fail to remedy stressful conditions.
A research team from the University of Nottingham's Department of Psychology has reported that stress can contribute to asthma, heart disease, arthritis, migraine, peptic ulcers and diabetes. They found that unlike in Sweden and America, where stress is taken more seriously, British bosses tended to blame personality and family problems.
The few stress-management initiatives that had been introduced were designed to help workers "cope" with their stress rather than control its sources in the workplace.
Kathy Parkes, from the Department of Experimental Psychology at Oxford University, who has reviewed the effectiveness of measures to tackle stress, said: "The findings so far are mostly but not entirely discouraging."
There was no evidence to suggest that stress-management consultants had improved conditions, she said. The few measures that were effective included flexi-time, more staff meetings with management and compressed working weeks of four 10-hour days.
Although much of the blame for stress is levelled against the practice of cutting staff numbers, the University of Shef-field's Institute of Work Psychology has found this may be one modern working practice which reduces stress.
If the firm is well-managed, remaining workers have a clearer role and a bigger part in the decision-making process.
Some of Britain's largest employers, wary of the cost of high rates of absenteeism and the possibility of over-stressed staff taking civil action, are taking the issue seriously. BP and Mobil have agreed to allow health and safety inspectors to study how changes in management have put pressure on their workers.
Last week the Health and Safety Executive issued new official guidelines outlining companies' responsibilities in protecting staff from stress.
Ms Bacon said it was vital to bring about a change in attitude among bosses, particularly of smaller and medium-sized firms.
"We have got to get employers to appreciate that it's okay to say you are stressed," she said. "It should not be the kind of thing that employees feel they must cover up."Reuse content