Millions of people are exposed to secondhand smoke every day. People living in multi unit housing are some of the most exposed. The only way to fully protect people from secondhand smoke at Scientists Warn Against Breathing in Secondhand Vape 'Smoke' Newsweek Secondhand Smoke and Electronic Cigarette Aerosol Resources US EPA Secondhand Vape Exposure: Effects, Who's at Risk, and More Exposure to secondhand vaping fumes among teens raises concerns UPI.com Avoiding Tobacco Smoke and E Cigarette Aerosol Is a Key Part of Asthma Management Asthma and Allergy Foundation of America