Re: In public...
In my experience it doesn't really matter if it's legal to smoke a narghile in public. I got hassled by police when I did it and even threatened by mouth breathing defenders of public morality that thought I was some sort of dupe fiend out to wreck the neighborhood. What matters is the sort of cops yuo have locally and what sort of people notice you doing it.
You should note that on a lot of campuses narghiles are banned it really doesn't matter if they are legally able to be smoked in public or not. Basically, if don't smoke on your own property do so a friend's place and save yourself the hassle.