OAKLAND (CBS SF) — The ninth, 10th and 11th Spare the Air alerts of the season were issued Thursday by the Bay Area Air Quality Management District for Friday, December 22 through Christmas Eve.

Representatives from the district say that dry, stagnant weather has created a high-pressure system over the Bay Area and is forecast to trap smoke near the ground and wood smoke is expected to build up in the region.

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Wood smoke is the major source of air pollution in the Bay Area in the wintertime and is especially harmful to children, the elderly and people with respiratory conditions, the district said.

These alerts ban the burning of wood, manufactured logs or any other solid fuel. This means wood burning both indoors and outdoors is illegal during this multi-day alert.

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The only exception is for homes without permanently installed heating where woodstoves or fireplaces are the only source of heat. Open-hearth fireplaces are no longer an exemption. Air levels will range from moderate to unhealthy for sensitive groups from today until Tuesday.

For more information on specific zones of the Bay Area, explanations of the Air Quality Index and general air quality knowledge please visit www.sparetheair.org.

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