It's cold outside, and curling up by the fireplace with a cup of cocoa may sound tempting.

But that won't be allowed because the Bay Area Air Quality Management District has declared today another "Spare the Air" day, the fifth this winter.

That makes it illegal for Bay Area residents and businesses to use fireplaces, woodstoves and inserts, pellet stoves, outdoor fire pits or any other wood-burning devices today. Homes where woodstoves or fireplaces are the only source of heat are exempt.

The ongoing high-pressure system and cool temperatures trap smoke pollution close to the ground, officials said.

"Wood smoke is the other secondhand smoke around our homes," Jack Broadbent, executive officer of the Air District, said in a statement. "It is important to reduce this smoke around our homes and neighborhoods when weather conditions trap smoke near the ground."

First-time violators are given the option to take a wood- smoke awareness class, online or by mail, to learn about the hazards of wood-smoke pollution in lieu of paying a penalty. Second violations result in a $500 ticket and subsequent ticket amounts are higher.

Read all of the PD's fire coverage here