SF6 Gas Insulated Substations I suspect. But please don't post the same question on multiple forums. It is against the rules. I'd recommend that you red-flag one of these and ask the moderator to delete it.
Thanks for the jokes (being snippy in the morning is a common problem amongst engineering types), the tips (I am a newbie on this forum and obviously never read the fine print, my bad and duplication has been deleted on one forum). So now that this is out of the way, if anyone in engineering land has dealt with Gas-Insulated-Switchgear in arc flash evaluations, I would be grateful for any comments or your experiences with it.