Would you tell a man he can't smoke in his own house?
In Oregon you can't smoke in any workplace or public building (Bars are exempt). this includes home offices if clients come to your office. unless you have a separate entrance to your office area this can be interpreted to mean your whole house.
as a non-smoker/anti-smoker (if you want to smoke at my house you can go sit on the porch with the dogs) I think this has gone way too far.
I spend most of my work days in paper-mills (not exactly a paragon of air quality), most are completely non-smoking properties now, including outside areas and in your car in the parking lot.
even the ones that allow smoking only allow it outside.
I spend most of my work day in the boiler-house, where they burn the toxic chemicals used in the pulping process (where you get that lovely smell from). and while we are their we are welding, grinding, and burning making huge amounts of smoke, that if compared to whats in a cigarette would make the smoker look like quite a light-weight. but guys aren't allowed to smoke while they do it.
personally I'd rather breath a little second hand smoke than spend my 12 hour day in a place where 20 out of the 50 guys are on a nicotine jones.
plus you get the added benefit of guys switching to chewing to get their nicotine (IMO chewing tobacco is the "Gross Nat'l Product"). I'd rather deal with a little extra smoke and a few butts laying around, than an increase in guys spitting all over the place.