Hello HR Zone, 

"E Cigs" are electronic cigarettes. Basically, they look like cigarettes but work by heating a solution that contains nicotine. This produces an odourless vapour which is inhaled. The user inhales this and gets their nicotine hit. When they exhale, you see a "vapour" which looks like smoke. In fact, the units look just like real cigarettes and the tips even glow when the user inhales.

 
As far as I can tell, there are no obvious health and safety implications as there is no flame, and the vapour that is released is not "smoke" – more like steam. I also believe this is not covered by the smoking ban, as you are not inhaling any tobacco products. There are reasons for and against allowing this in the workplace, but I wondered whether anyone else had encountered this, and if so, how they dealt with it. 

Thanks in advance for your help,

Charlie