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 Should I Be Concerned About Secondhand Vaping? Secondhand Smoke and Secondhand Vaping: Both Bad for Kids University Hospitals Secondhand Vape Exposure: Effects, Who's at Risk, and More Juul study shows secondhand vaping emissions are less toxic than cigarette smoke Secondhand Smoke and Electronic Cigarette Aerosols US EPA