The percentage of U.S. homes with smoke-free rules increased from 43 percent in 1992-1993 to 83 percent in 2010-2011, according to a new study by the Centers for Disease Control and Prevention.

Over the same period, the study found that among households with no cigarette smokers, the national percentage of smoke-free home rules increased from 56.7 percent to 91.4 percent. The increase was even more dramatic among households with one or more adult smokers; the national percentage of smoke-free home rules increased nearly five-fold, from 9.6 percent to 46.1 percent.

However, the fact that less than half of all households with smokers have adopted smoke-free rules is still a concern, because nearly all nonsmokers who live with someone who smokes inside the home are exposed to secondhand smoke. The home is a major source of secondhand smoke exposure, especially for children. Exposure to secondhand smoke causes more than 41,000 deaths among nonsmoking adults each year, and causes respiratory problems and SIDS among children.

Read more from CDC.