Causes of Carbon Monoxide Poisoning in Homes

A few simple moves can make a big difference in prevention.
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Written by Erin Oppenheim
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Edited by Tina Orem
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To prevent carbon monoxide poisoning and keep your family safe, you can install carbon monoxide alarms outside each bedroom and on every level of your home, ensuring they are unobstructed by furniture or curtains

Texas Department of Insurance. How to avoid carbon monoxide poisoning at home. Accessed Jun 26, 2024.

Malfunctioning or incorrectly used fuel-burning appliances can release carbon monoxide, as can idling cars. Every year, hundreds of people die accidentally from carbon monoxide poisoning, according to the Environmental Protection Agency

U.S. Environmental Protection Agency. Protect Your Family and Yourself from Carbon Monoxide Poisoning. Accessed Jun 26, 2024.

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What is carbon monoxide?

Carbon monoxide (CO) is a colorless and odorless gas produced by burning fuel in cars, small engines, appliances and heating systems.

Exposure to carbon monoxide can make you feel very ill; high levels can kill. According to the Centers for Disease Control and Prevention (CDC), symptoms of carbon monoxide poisoning often mimic the flu, causing headaches, dizziness, weakness, nausea, vomiting, chest pain, and confusion

Centers for Disease Control and Prevention. Carbon Monoxide Poisoning Basics. Accessed Jun 26, 2024.
. People often ignore the early symptoms of CO poisoning, which can lead to continued exposure, loss of consciousness and accidental death.

What causes carbon monoxide to build up in a house?

According to the American Lung Association, faulty or improperly vented appliances are the most common causes of carbon monoxide buildup in homes — especially following a power outage or emergency. These include:

  • Fuel-burning appliances such as your furnace, range, oven, water heater or clothes dryer.

  • Gas or wood fireplaces and wood stoves.

  • Coal or oil furnaces. 

  • Space heaters, including oil and kerosene heaters.

  • Charcoal grills and camp stoves. 

  • Gas-powered equipment like lawn mowers and power tools.

  • Car exhaust fumes, particularly if your home has an attached garage

    American Lung Association. Carbon Monoxide. Accessed Jun 26, 2024.

Tobacco smoke is also a source of carbon monoxide buildup in the home, especially without proper ventilation

Minnesota Department of Health. Carbon Monoxide (CO) Poisoning in Your Home. Accessed Jun 26, 2024.

7 ways to help prevent carbon monoxide poisoning

Here are some of the easiest ways to help keep carbon monoxide from building up in your home.

  1. Install battery-operated or battery-backup carbon monoxide detectors. Consider purchasing detectors that sound an alarm and have a digital readout that displays peak CO levels. To ensure proper function, regularly check the batteries and replace your CO detector every five years or follow the manufacturer’s recommended replacement date.

  2. Have your fireplaces and fuel-burning appliances professionally serviced and inspected annually. Do this ahead of the heating season. Ensure flues and chimneys are connected, undamaged and free of blockages


  3. Buy vented fuel-burning appliances. Look for appliances or tools with the seal of a national testing agency. Ensure they are professionally and properly installed, and follow the manufacturer instructions and maintenance recommendations. Be careful using an unvented gas or kerosene space heater; make sure you use the recommended fuel type, keep interior doors open and crack a window for ventilation. 

  4. Avoid using ovens or clothes dryers for heat. This applies even if it’s just for a short time

  5. Operate generators outdoors only. Make sure they’re at least 20 feet from your home and any doors, windows or other openings. Never use a generator indoors, even with ventilation. Use a battery-powered or battery backup CO detector inside your home if you’re using a generator.

  6. Never use a charcoal grill or portable gas camp stove indoors. Burning any kind of charcoal gives off CO. Avoid using portable flameless chemical heaters (MRE heaters) indoors as well.

  7. Keep your vehicle properly maintained. Schedule annual exhaust system inspections for your car or truck to detect potential leaks. Never run a vehicle inside an attached garage, even if the garage is open. For detached garages, open the door and windows if the car is running inside. If your running vehicle has a tailgate that's open, also open the vents or windows to get air moving through. This can help prevent CO buildup Carbon Monoxide Poisoning Basics. Accessed Jun 26, 2024.

Frequently asked questions

Carbon monoxide alarms typically last between five and seven years, but this can vary by manufacturer. Check the manufacturer's instructions for the recommended replacement date. The CDC recommends replacing your CO detectors every five years.

Evacuate everyone outdoors immediately. Call 9-1-1 and remain outside until emergency responders say it’s safe to return inside. If you think you were exposed to the CO for a long time or you have symptoms of carbon monoxide poisoning, go to the emergency room


Common symptoms are headaches, dizziness, weakness, nausea, vomiting, chest pain, or confusion. If you’ve been exposed, go to the emergency room immediately. You can confirm exposure or carbon monoxide poisoning with a blood test


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