I'm not sure on the details but just throwing out what I've seen in NY. Smoke shops around here seem to allow smoking indoors, I assume there are special provisions for that type of business.

There is also a bar around here that has a separate smoking room. They have a large air filtration system hanging from the ceiling in there, not sure if thats why they can get away with it. There is even a little door in the wall where they can serve drinks to you while you're in there.