There is a great amount of work available in the literature for breakdown and corona in uniform field gaps at power frequency (50/60 Hz) and dc. The general consensus is that the breakdown voltage increases with humidity [3, 4]. With an increase in the humidity, electron attachment increases. It also causes reduction on secondary emissions due to the absorption of photons by water molecules. Both of these factors increase the breakdown voltage with humidity [5]. In contrast, there is very little work reported on the breakdown characteristics at VLF/LF [1, 2].