More than 15,000 Americans get sick from carbon monoxide every year and the odorless, toxic gas kills 480 people, the Centers for Disease Control and Prevention said on Thursday.

Most people got sick in their homes and the few who had carbon monoxide detectors were all alerted by them, the CDC said. “Efforts are needed to educate the public about preventing carbon monoxide exposure,” it said.

The CDC used a survey of emergency room records done by the Consumer Product Safety Commission for its study, released as part of the weekly CDC report on death and disease.

“During 2001-2003, an estimated 15,200 persons with confirmed or possible non-fire-related carbon monoxide exposure were treated annually in hospital emergency departments,” the CDC report reads.

It said 9.3 percent of those treated had a carbon monoxide detector at home and all of them said the detector had alerted them. These detectors resemble smoke alarms and often are sold in combination with a smoke alarm.

“Most (64 percent) of the nonfatal carbon monoxide exposures occurred in homes,” the CDC said. An estimated 18 percent of these were due to faulty furnaces, although in many cases the source was unknown.

Carbon monoxide poisoning almost always causes a headache and can also cause nausea and dizziness.

People can be sickened or killed if they light gas grills or barbecues indoors - something often seen during power outages.

Nine percent were sickened or killed in a car. Automobile engines produce carbon monoxide, which can leak into the passenger compartment or be deliberately piped in, in the case of suicide or murder.

SOURCE Morbidity and Mortality Weekly Report, January 21, 2005.