The Trades Union Congress (TUC) is aiming to train 15,000 safety reps, in a bid to make the workplace a healthier and environment.
Together with unionlearn, the TUC is also publishing a new guide to occupational health, as part of a campaign to help the estimated two million employees who fall sick every year because of work.
The TUC workbook says that 175 million working days were lost as a result of sickness absence in 2006, costing firms £650 per poorly employee.
TUC general secretary Brendan Barber said: "Workplaces where there are union safety reps tend to be both safer and healthier places. But the UK is currently facing an epidemic of occupational ill health. Many people are ill and in pain as a result of lifting injuries, slips and trips, stress and noise-induced hearing loss suffered either at, or caused by, their work.
"Using this workbook, union reps can learn about all the aspects of occupational health. Then they can use it to encourage their employers to do much more to make employees feel they are getting a decent level of support from work when they are ill and again when they are on the road towards a full recovery."
