There is no dispute around the harmful effects of smoking tobacco or the problems associated with secondhand smoke.
Battery-powered e-cigarettes that turn liquid nicotine into vapor emit no smoke. Research has yet to conclude secondhand inhalation from vape equipment has ill effects that should be the basis of public vaping bans.
A German study that looked at whether e-cigarettes cause "passive vaping" found virtually no quantifiable levels of the 20 volatile organic compounds present in cigarette smoke.
The German Cancer Research Center, however, did detect the minute presence of metals and carcinogenic chemicals in the vapors. So further study is warranted.
Part of the problem for e-cigarettes is that the user may appear to be smoking, which is why cities are enacting regulations similar to tobacco.
Colorado already bans e-cig sales to anyone 18 or younger. And the federal government would be wise to ban marketing to teens, including flavors and colorful packaging aimed at youngsters.
Private businesses should be allowed to prohibit vaping and the practice should be banned from government facilities. The U.S. Department of Transportation banned vaping in 2011. Amtrak also has prohibited it.
But bars, restaurants, bingo halls, concert venues and bowling alleys should be allowed, for the time being, to permit the practice if they want, unless further research proves the activity dangerous to the non-vaping public.