Personally i dont smoke in home, haven't for years, but just how harmful is second hand smoke, especially when you say they dont smoke infront of them whilst they are there. if its the smell, then will you not take them into a chip shop or a fish market, just to put this political correctness into some perspective one little burp by Mt Etna has already put more than 10,000 times the CO2 into the atmosphere than mankind has in our ENTIRE time on earth yet were spending billions on reducing our CO2 emissions?