Posted By alan noble The smoke free legislation allows you to smoke as soon as you are in the open air. However many employers including the Health Service have introduced smoking policies which state a distance you must be away from their buildings before you can smoke (I have seen signs stating 15 metres.) There seems no logical reason for the distance of 6 metres or 15 metres , down wind or otherwise. Sounds like a 'comfort distance' i.e. a distance by which employers believe will minimise the chance of tobacco smoke entering premises to the discomfort of their non-smoking employees. I don't think anyone will have gone to the expense to carrying out specific tests. Too many variables like number of smokers, distance..and yes,the prevailing wind direction. As far as the HSE (and IOSH)are concerned and their preceived lack of involvement, it should be remembered that smoke free legislation was brought in under public health legislation (not H&S)which is why Scotland could go it alone before the rest of the UK. Consideration can be given as much as to whether environmental tobacco smoke is 'prejudicial to health or a nuisance' under EPA 1990 as to whether there is a risk under H&S.