Yes, we have had our share of static charge problems in winter, so we have tried to adopt a policy of 'self grounding'. We had one user who had a particular ability to generate a lot of voltage, don't know if it was footware or genetics, but the same thing eventually happened - spark hit the rollers and we were down (SX50). When it came back up we found a 68000 board had failed, so the ESD killed some DRAM... ouch. I have tried through the years to get some ESD dissipative flooring solution like they use in semiconductor Fab rooms, but for reasons we don't need to get into, those efforts failed. Both Cameca and JEOL seem to have maximum humidity level requirements, but not minimum. Unofficially, I hear now that 40 to 60% relative humidity is a good target range. I would still be interested in input regarding everyone's lab environment, and experiences.