It's that time of year when firefighters are called to respond to blaring carbon monoxide detectors.
Windows and doors are kept shut to keep the cold out, so fresh air doesn't always get circulated in homes.
Carbon monoxide is a tasteless, odorless, colorless gas that can cause sudden illness and death, according to the Centers for Disease Control and Prevention.
But when detectors go off, it doesn't always mean a furnace or water heater has malfunctioned. Most of the time, the detectors go off in error, fire officials said.
Fire officials said even though most carbon monoxide calls are false alarms, residents still should call 911 to get emergency personnel to their home.
"We'd rather go out on 10 false calls than one bad call," said Layton Fire Marshal Dean Hunt.
The false alarms usually occur because the carbon monoxide detector needs to be replaced or cleaned, said Ogden Fire Chief Mike Mathieu.
CO poisoning symptoms
The most common symptoms of CO poisoning are headache, dizziness, weakness, nausea, vomiting, chest pain, and confusion. High levels of CO inhalation can cause loss of consciousness and death. Unless suspected, CO poisoning can be difficult to diagnose because the symptoms mimic other illnesses. People who are sleeping or intoxicated can die from CO poisoning before ever experiencing symptoms.
Source: Centers for Disease Control and Prevention website
Hunt said carbon monoxide detectors need to be replaced every seven to 10 years. The best way to decide when to change the detector, he said, is to check with the manufacturer.
Sometimes, though, the detector goes off before it is time to replace it. If no one in the home is showing any signs of carbon monoxide poisoning, the occupants can take the alarm outside, let it get some fresh air and then hook it back up. If it goes off again, call 911, Hunt said.
Mathieu said it is also important to clean the detectors regularly.
"Sometimes dirt gets accumulated in the sensors and they just go off," Mathieu said. "If they are dirty, they will give a false alarm."
He suggested that residents use the nozzle of a vacuum cleaner to remove dust and other particles from the detectors.
Utah passed a law that requires all residences built after 2005 to have carbon monoxide alarms.
Ogden is the only Utah city that requires all homes to have a carbon monoxide alarm.
Mathieu said he had pushed for the alarms to become mandatory since 1994.
Mathieu said even though Ogden requires carbon monoxide alarms, not all homes have one. Residents can buy one for $10 at the city office.
Those who live outside of Ogden can get a carbon monoxide detector at any hardware store. Prices range from $15 on up, depending on the type of detector.
Mathieu said firefighters carry a carbon monoxide detector with them, which has come in handy more than once.
In one case, emergency personnel were working on a patient they thought had a heart attack. As they were leaving, their carbon monoxide detector went off, indicating high levels of the gas in the home.
Firefighters got the other residents out of the house, notified the hospital the patient was being talked to about the carbon monoxide, and helped the patient avoid unnecessary tests, he said.
"Carbon monoxide poisoning is the most undiagnosed problem," Mathieu said.
According to a survey done by American Housing in 2009, about 47 percent of all residences have a carbon monoxide detector installed.
In 2009, according to the American Journal of Emergency Medicine, 552 people across the country received hyperbaric oxygen treatment for carbon monoxide poisoning.