One of winter's most dangerous killers is likely inside your home.

Fire and emergency officials say carbon monoxide-a colorless, odorless, invisible gas-is one of the most dangerous factors about cold weather.

The gas is formed when any kind of fossil fuel is burned. While you can smell and see smoke, Elizabethtown Fire Chief Jamie Fulk said "no one can see or smell carbon monoxide."

"People will say sometimes they can smell carbon monoxide," he said, "but what they smell is simply the other products being produced by whatever is creating the carbon monoxide."

The gas slows breathing and causes a euphoric effect, causing most victims to go to sleep. Its effects are easily treated with fresh air. Without treatment, carbon monoxide poisoning can lead to asphyxiation and death.

Bladen County Emergency Services Director Mitchell Byrd said one man died earlier this year when he and a friend tried to stay warm in a van using a camp stove. Byrd said he knew of no other recent carbon monoxide related deaths.

"We'd like to keep it that way," Byrd said. Carbon monoxide is still a very serious concern."

Fulk said many carbon monoxide deaths come from "people trying to stay warm."

While many people open windows or use air-filtering cooling systems in the summer, most homes and businesses are sealed as tightly as possible against cold weather.

By sealing the cold out, Fulk said, you can also seal carbon monoxide in.

"Anything that produces heat can produce carbon monoxide," Fulk said.

Gas logs, gas heaters, water heaters, oil furnaces, wood stoves, kerosene heaters, and other appliances can produce dangerous amounts of carbon monoxide if they aren't functioning correctly.

Attached garages can also be a source for carbon monoxide, Fulk said.

"People need to use care when they park a vehicle inside a garage and close the door," he said. "Never run an automobile or other engine in a closed garage."

The best way to avoid carbon monoxide poisoning, Fulk said, is to have a carbon monoxide detector. The devices run around $25, and work under the same principle as smoke detectors, emitting a loud alarm if carbon monoxide levels reach the danger point.

"This is almost as important as a smoke detector," Fulk said.

Fulk said if the alarm goes off, the owner should call the fire department. Fulk said firefighters can determine if a carbon monoxide leak is present, as well as ensure the alarm isn't activated due to an undiscovered fire.

"If you have a detector," Fulk said, "it could very well save your life."

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