Air pollution regulators are asking Bay Area residents to refrain from burning wood fires on Thanksgiving Day to protect air quality.

However, the request is voluntary, because air pollution is not expected to get quite bad enough to warrant a Spare the Air alert, said Bay Area Air Quality Management District officials.

"To protect our families and neighbors from the hazards of wood smoke, please refrain from using fireplaces or wood stoves," Jack Broadbent, the district's executive officer said in a written release.

Cold stagnant air this week trapped smoke and other fine particles near the ground, resulting in Spare the Air alerts issued Monday and Tuesday to ban wood fires.

Health experts say smoke from wood fires can aggravate asthma, bronchitis and emphysema and even trigger heart attacks.   (Bay Area Air Quality Management
Health experts say smoke from wood fires can aggravate asthma, bronchitis and emphysema and even trigger heart attacks. (Bay Area Air Quality Management District)

While the air quality has improved since then, the Bay Area continues to have elevated pollution concentrations, Broadbent said.

The agency regulates air pollution in seven Bay Area counties, except for southern Solano and Sonoma counties.

Contact Denis Cuff at 925-943-8267. Follow him at Twitter.com/deniscuff