Posted By Dave Daniel I think that you will find most modern equipment includes filters. All electrical equipment produces some ozone and there is a theoretical risk, but I've only come across significant levels in welding (TIG welding produces significant levels from the arc) Dave Daniel - H&S Consultant

Posted By Robert Woods Keighley Worksafe produce a leaflet on photocopier safety it says that best practice is that phtocopiers are sited at least three metres from workers in a well ventilated area. For a free Copy give them a ring on 01535 664462

Posted By Rob Todd To Jay Joshi, I'm afraid I must entirely disagree with you in respect of safe distances. If something, whether it is a substance, noise or piece of equipment is at a safe distance then it is by definition safe. The reason safe distance isn't in the heirarchy of measures under COSHH is that it is common sense that if there is no hazard by distance, there is no need to take further action. Remember anyway, where there is an OES and the OES is not exceeded, there is no hazard, as opposed to an MEL which has no safe level. We do of course wish to make life healthier for staff and as such we will attempt to bring levels of anything unnatural down to the lowest level but in recent tests I had carried out in an office with both photocopiers and laser printers - levels recorded were a twentieth of the OES for 03. With regards Rob

Posted By Mark Preston In defence of Jay... You can use safe distance to control the risk from radiation because it behaves predictably (inverse square law). You can use distance to prevent the risk of injury from moving parts - providing you can be absolutely confident that they will only move in a predictable manner (and you can control the movement of people in the vicinity). But you can't reliably predict the movement of gases or airborne particulates, and these are the hazards we are talking about. Even if (big if) you knew the rate of generation of the gas, and applied Graham's law to detemine its rate of diffusion, in the real world you could still be out by an order of magnitude because of the other variables - not least those that Jay mentions. That's why control by distance isn't an option under COSHH and why setting a safe distance from a gas is not just over simplistic - it's scientifically flawed. As for Richard's argument - with sufficient wind speed, I'd sooner be 10 metres upwind of a toxic gas than 100 metres downwind ;)

Posted By Jane Blunt Dear all There is another factor to take into account with ozone. It has a tendency to decompose, back into oxygen. This takes place readily on surfaces, or particles of dust, so at a distance from the source, there is a chance that not only has it been dispersed but that it may have decomposed altogether, Regards Jane