Dec 16, 2013 11:01 AM EST By Staff Reporter, UniversityHerald Reporter

No indoor and outdoor fires for the ninth straight day in the Bay Area after government officials continued its "Spare the Air" alert on Monday, CBS reported.

Cold weather throughout the month of November and December trapped pollutants near the ground and created air quality deemed unhealthy by The Bay Area Quality Management District, according to CBS. The district has banned man-made fires 13 days in total since November 1. Residents who heat their homes by burning wood are exempt.

"We appreciate the cooperation of Bay Area residents in reducing their wood burning during this long spell of dry and stagnant weather," BAAQMD executive officer Jack Broadbent said in a statement.

Smoke from improperly burned wood, such as in outdoor camp fires or indoor fireplaces, is the highest source of air pollution during the winter season, according to sparetheair.org. If the wood contains harmful chemicals, it can emit three different types of pollutants, according to the EPA: hazardous air pollutants (HAP), fine particle pollution (ash), and volatile organic compounds (VOC).

"Because still weather and high pollution levels have persisted in the region, the Air District is extending this Winter Spare the Air Alert for another day," Jack Broadbent, the air district's executive officer, told the San Jose Mercury News on Dec. 9 when the ban was extended for the third straight day.

Spare the Air also recommended finding alternative ways of transport, such as biking or walking to help limit air pollution. Residents can also try to supplement their car use with public transportation. "Air season" lasts until February 28.  

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