Electronic cigarette signage

Electronic cigarette usage does not have regulated safety sign design yet as they are such a new item.

Working with safety sign development, I have had to create an icon to be used for these items when certain establishments would like the option of prohibiting or permitting the use of these within public areas. There is a concern not to make it look like a battery as it contains polarization symbols to reflect it's electric power. Also, as these use liquid vapour, there isn't actually any smoke created at the tip of the cigarette, just within the users mouth, so that raises another concern which is, should there be smoke/vapour illustration at the tip to coincide with the item being a cigarette and retaining a connection to standard cigarette signage.