First off, I am not only a non-smoker but also an asthmatic...
Being near people smoking (or heavy smog or Microwaved popcorn or any of a number of other reasons for smoke particles in the air) makes me physically ill...We are not just talking bothered or irritated here...my bronchial passage linings swell up and the passages constrict--sometimes to the point of virtual closure...I wheeze and gasp and have trouble breathing...I usually have to physically leave the room or use my inhaler...but most often BOTH...and most smokers are so insensitive and unaware...they think it's their god-given right...
That said, Celebrity, Princess and virtually every other cruise line (save Carnival's Paradise which is strictly smoke-free) have about the same rules nowadays: No smoking in the Dining Rooms or Showroom, rest of the ship split 50/50 down the middle...
The problem to watch out for is that the smoke itself doesn't quite no where that halfway mark is...so it doesn't stop at the line...Unfortunately, neither do some of the smokers...
The bigger difference in the amount of smoke comes with the itinerary, not the line...
European itineraries draw more Europeans and they tend to smoke a lot more than we do...
Want the least smoking (other than the Paradise)? Do a Mexican Riviera cruise out of LA or San Diego...Those cruises have large numbers of Californians...And California has by far the lowest per capita consumption of tobacco products of any state...as well as a longstanding history of no smoking laws for bars, restaurants, workplaces, etc.
We did the Mexican Riviera out of San Diego on the Grandeur last year and I don't recall seeing a single person lighting up anywhere the whole length of the cruise (and trust me, I would have noticed)
