Posted By 9-Ship I have quite a bit of DSEAR experience. I guess the obvious solution would be to investigate if it is possible for your man to take his hearing aid off while in the Zone 1 area. Second, can some one else do the work who doesn't wear an hearing aid. Also can work be carried out to the equipment/system etc to re-rate as a Zone 2 or even better to re-classify as non-hazardous area i.e. better containment, enclosed systems for handling the HFLs. Can u be a bit more specific about the scenario/situation?

Posted By holmezy Wayne, in normal circumstances, the designated zone (0,1 or 2 gas, 20,21 or 22 dust) will determine what type of electrical equipment is permitted to be used in the area, however, some consideration has to be given to assess the potential for other equipment to generate a spark, and for that spark to have enough energy to cause ignition. I would consider that a hearing aid with 1 to 1.5v (that is probably intrinsically safe by design, if not by intention) would not constitute a risk of spark or ignition. The battery is also in permanent contact with the poles so there would be no gap for any such spark to arc across nor is the dropping of the ear piece likely to generate a spark, even if the battery was dislodged. Body of the aid is usually plastic so not likely to spark on impact. Not a great risk in my view, however, I suppose it depends on the concentration of dust or gas, flammability levels, extraction, current control measures and proximity of the blokes head to the cloud or gas pocket? You could always fit the wearer with an earthing strap or equi-potentially bond him! Holmezy got to stop my dogs getting at next doors chickens before I can have a beer tonite!!