Spare the Air Alerts that ban the burning of wood will be in effect through Saturday in the Bay Area because of a forecast for high levels of pollution, regional air quality officials said.

The Bay Area Air District had previously issued an alert for Thursday and extended it through Saturday because of cold temperatures and offshore winds that have led to high levels of pollution in the region.

On Spare the Air days, it is illegal for residents and businesses to use their fireplaces, wood stoves, pellet stoves, outdoor fire pits, or other wood-burning devices. There are exemptions, such as for homes without permanently installed heating, according to the air district.

People found to have violated the wood burning ban will be encouraged to take a wood smoke awareness course if it is their first offense. Violators who don’t take the course will receive a $100 ticket, and subsequent violations will lead to higher fines.

Wood smoke exposure has been linked to respiratory illnesses and an increased risk of heart attacks and some types of cancer, and is particularly harmful for children, older adults, and those with pre-existing respiratory conditions, air district officials said.

Dan McMenamin is the managing editor at Bay City News, directing daily news coverage of the 12-county greater Bay Area. He has worked for BCN since 2008 and has been managing editor since 2014 after previously serving as BCN’s San Francisco bureau reporter. A UC Davis graduate, he came to BCN after working for a newspaper and nonprofit in the Davis area. He handles staffing, including coaching of our interns, day-to-day coverage decisions and management of the newswire.