This site was created in cooperation with the Regional Homeland Security Coordinating Committee, and is supported by funding from the Department of Homeland Security.
Carbon monoxide (known by the chemical symbol CO) is a colorless and practically odorless gas. It is poisonous to people and animals, because it displaces oxygen in the blood. It is produced by the incomplete burning of solid, liquid, and gaseous fuels. Appliances fueled with natural gas, liquefied petroleum, oil, kerosene, coal, or wood may produce CO. Burning charcoal and running car engines also produce CO.
Every year, thousands of people are treated for CO poisoning in emergency rooms, and more than 200 people in the U.S. die from it.
Carbon monoxide can have different effects on people based on its concentration in the air that people breathe. Because you can’t smell, taste, or see it, you cannot tell that CO gas is present. The health effects of CO depend on the level of CO and length of exposure, as well as each individual’s health condition.
The initial symptoms of CO poisoning are similar to the flu (but without fever). They include headache, fatigue, shortness of breath, nausea and dizziness. Many people with CO poisoning mistake their symptoms for the flu. Because CO replaces oxygen in the blood, it can make people feel sleepy, or prevent those who are asleep from waking up.
At higher concentrations, people can experience impaired vision and coordination, headaches, dizziness, confusion, and nausea. In very high concentrations, CO poisoning can cause death.
Install carbon monoxide detectors/alarms in homes and recreational vehicles. Place them in hallways near sleeping areas. Follow manufacturer’s instructions regarding the specific location for installation. Avoid corners where air does not circulate.
If you think you or your family are experiencing any of the symptoms of CO poisoning, get fresh air immediately. Open windows and doors for more ventilation, turn off any combustion appliances, and leave your home. Then call your fire department and report your symptoms. You could lose consciousness and die if you do nothing. It is also important to contact a doctor immediately for a proper diagnosis. Tell your doctor that you suspect CO poisoning is causing your problems.
Prompt medical attention is important if you are experiencing any symptoms of CO poisoning when you are operating fuel-burning appliances. Before turning your fuel-burning appliances back on, make sure a qualified serviceperson checks them for malfunction.
Treat the alarm signal as a real emergency each time. If the detector/alarm sounds and you are not experiencing any symptoms described above, press the reset button. If the alarm continues to sound, call the fire department. Immediately leave your home until a professional checks to find the reason why the detector/alarm sounded, and any problems are fixed.
For more information about carbon monoxide poisoning, contact your local emergency manager or public health department.