Carbon Monoxide (CO) is a colorless. orderless gas produced by the 
incomplete burning of any carbon-containing material including gasoline, natural gas, propane, coal or wood. CO is dangerous because it replaces oxygen in the blood and interferes with the transport of needed oxygen to cells in the body. That is a little technical but it gets the point across, Carbon Monoxide is bad for you.
Each year, nearly 5,000 people in the United States are treated in hospital emergency rooms for Carbon Monoxide poisoning. However, this number is believed to be a lowball of CO poisoning because many people with CO symptoms mistake the symptoms for the flu or are misdiagnosed.
Common sources of CO include the following wood or gas fueled appliances:
• Room heaters
• Furnaces
• Charcoal grills
• Cooking ranges
• Water heaters
• Automobiles run in closed garages
• Fireplaces
• Portable generators
• Wood burning stoves
Symptoms of CO poisoning can mimic those of the flu or food poisoning. Early exposure symptoms may include:
• Dizziness
• Nausea
• Headache
• Weakness
• Inattention
• Fatigue
Because CO poisoning symptoms mimic the flu or food poisoning, it is important to inform medical responders of the possibility of exposure to excessive amounts of CO. Poisoning can be reversed if caught in time, but acute poisoning can result in permanent damage to the heart and brain.
Take some time to make sure home is carbon monoxide free:
• Have a qualified service technician should perform preventive maintenance on homes with central and room heating appliances (including water heaters and gas dryers) annually. The technician should look at the electrical and mechanical components of appliances, such as thermostat controls and automatic safety devices.
• Chimneys and flues should be cleaned annually and kept free of blockages, corrosion, and loose connections.
• Individual appliances should be serviced regularly.
• Kerosene and gas space heaters (vented or unvented) should be cleaned and inspected to ensure proper operation.
You know what they say about an ounce of prevention: You can buy a carbon monoxide detector for as little as $20.00 at hardware and discount stores. The device can detect toxic concentrations of CO in the air and sound an alarm. Not a lot to safeguard yourself and your family from the "cold weather killer"!