As temperatures around the Bay Area start to cool and heaters are turned on, residents are being reminded to have working carbon monoxide alarms at home to prevent accidental gas poisonings.

Carbon monoxide is a colorless, odorless gas produced from heaters, fireplaces furnaces and many types of appliances and cooking devices.

Each year, 480 people in the U.S. are killed by carbon monoxide poisoning, and as many as 20,000 are hospitalized, according the San Carlos Fire Department.

The best way for homeowners to stay protected from carbon monoxide is to have a CO2 alarm installed on every floor and outside each sleeping area, officials said.

As of July 1, 2011, California law requires owners of single-family homes with attached garages or fossil fuel sources for heating to install carbon monoxide alarms in the home.

More information on carbon monoxide can be found online.

— Bay City News Service

Are you receiving Express, our free daily e-mail edition? See a sample and sign-up for Express.