Due to continued poor air quality around the Bay Area, Friday has been declared the third winter Spare the Air Day of the season.

The Bay Area Air Quality Management District announced today that air quality was expected to continue to be unhealthy, for the third consecutive day, and that wood burning, both indoors and outdoors, will be illegal all day Friday.

The alert bans the burning of wood, manufactured firelogs, or any other solid fuel.

The ban will be in effect in for Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, southern Sonoma and southwestern Solano counties, district officials said.

During winter months, wood smoke is the leading cause of air pollution in the Bay Area, according to district officials.

Wood smoke contains harmful pollutants, such as soot and carbon monoxide, and toxins such as dioxin, which has been linked to increased cancer rates in adults.

About one-third of the harmful soot in the winter air can be attributed to smoke from the 1.4 million fireplaces and wood stoves in the Bay Area, according to the district.

More information about the ban and on whether it is in effect can be found at www.sparetheair.org or by calling (877) 4NO-BURN (466-2876).

Those wishing to receive automatic phone calls when a Winter Spare the Air alert is issued can register for the alerts by calling (800) 430-1515.

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