Carbon monoxide (CO) is an odorless, colorless, and poisonous gas. You can not see, taste or smell carbon monoxide which makes it almost impossible to detect. For this reason every home should have a carbon monoxide detector. When inhaled, carbon monoxide enters the lungs and bloodstream where it eventually replaces your body's oxygen, resulting in suffocation. Exposure to extremly high levels of carbon monoxide can cause death within minutes. Symptoms of carbon monoxide poisoning include headache, dizziness, lightheadedness, nausea, weakness and shortness of breath.
Should your carbon monoxide detector go off, or you suspect the presence of carbon monoxide, get outside into fresh air immediately. If you cannot get outside be sure to open as many doors and windows as possible. Carbon monoxide can be produced by both wood, oil furnaces, propane appliances, and fireplaces and can be caused by blocked chimneys, leaking chimney flues, cracked heat exchangers or improper venting.