We have a workshop that may or may not fall under the DSEAR Regulations, therefore we are trying to determine this and if so what zones we are likely to have. In addition to looking at the substances we have, the activities we undertake and the existing controls we are also considering atmospheric testing to establish actual concentrations on site. However my particular question relates to the benefits of this. As I see it the results will either tell us; 1) At the time of testing the atmosphere was explosive (fine, then we know and move forward) or 2) At the time of testing the atmosphere was NOT explosive. However I am unsure what the advantage of this would be as depending on our inventory / processes (spray painting) it could always be said there was the potential for an explosive atmosphere to develop and as I understand DSEAR (which may be wrong) we would still fall under the regulations. Therefore regardless of the Atmospheric Testing results (positive or negative: if I can use such a phrase) it seems to me our actions will have to be the same. Am I correct? If so there appears limited point in testing. Or could we use the results as evidence that the workshop does not come under the DSEAR Regulations. Finally; if my understanding of atmospheric testing is wrong please feel free to advise on the different types, what they are designed for and what benefit the offer. Sorry if this is a rambling thread but I am struggling with this one (despite have read a mountain of publication on DSEAR) Cheers

Leslie: From work in the Motor Industry years ago I can report that if you use an explosimeter inside a zoned area you are unlikely to find any concentration of flammable vapours. The "traditional" standards set distance parameters which include two sets of belts and braces. We found you needed to put the sensor right above a pool of solvent on the floor to get a reading. Your best bet is to go for "traditional" zoning distances based on BS or other standards as previously advised. Bear in mind that these days less and less paints have low flashpoint solvents and there is a strong move to water-based products for environmental reasons.