FISA has recently been requested advice on blood alcohol levels for chainsaw operators - below is some guidance:
The Government's guidance on sensible drinking, published in December 1995 lists the following as examples of specific situations when the best advice is to not drink at all:
If the operator needs to drive to work, he will need to be below the legal drink/drive limit. Even at blood alcohol levels lower than the legal drink/drive limit, alcohol reduces physical co-ordination and reaction speeds.
If you knowingly allow an employee under the influence of excess alcohol to continue working and this places the employee or others at risk, you could be prosecuted. Similarly, your employees are require to take reasonable care of themselves and others who could be affected by what they do.
An agreed alcohol policy can help detail to employees how they should behave to ensure that their alcohol consumption does not have a detrimental effect on their work.
A good leaflet to have a look at is on the HSE.gov.uk website - INDG240.