I didn't need this article to know that second hand smoke is not very dangerous. Smokers have to suck down two packs a day for decades before they ever develop cancer.
How does anyone figure that being exposed to a few whiffs of diluted cigarette smoke in the air is going to kill them?
Watch the reaction of some anti-smoking nazis to tobacco smoke.
They really do!
They believe that if something is dangerous, even the most minute amount contains enough risk that they should scream bloody murder. If driving 100 mph through a residential neighborhood is demonstrably dangerous, then driving one hundredth of a mile per hour also contains danger and must be eliminated.