Sonoma County supervisors unanimously approved a resolution Tuesday that will ban smoking inside apartments and condominiums in the county's jurisdiction.
The ordinance was part of a larger anti-smoking package that seeks to bring the county in line with cities like Sebastopol that have strict smoking prohibitions.
A vote on a proposal that would have banned smoking on county property and unenclosed areas such as restaurant and bar patios was delayed until October to give food and beverage businesses more time to brace for the change.
"This is a major step forward in protecting the health of all residents and visitors to Sonoma County," Mark Netherda, the county interim public health officer, said after the vote.
The ordinance will prohibit smoking in any existing multi-unit residence beginning in 16 months. It will ban smoking in new units, as well as those rented for residential use for the first time, in 8 months.