How to Prevent Carbon Monoxide (CO) Poisoning


We’ve all seen the tragic headlines and heard the awful stories:  “Couple Perishes From Faulty Furnace”.  “Six People Die From Generator Operating In House”.  “Proper Chimney Inspection Could Have Saved Family”.  Hundreds of people are seriously injured or die every year because of carbon monoxide (CO) poisoning.

This article will give you an overview of CO poisoning.  We’ll discuss the symptoms and give you simple precautions and practical tips to protect your loved ones.


Carbon monoxide is a poisonous gas.  You cannot smell it, you cannot see it and you cannot taste it.  By breathing in CO fumes, your body replaces the oxygen in your red blood cells with carbon monoxide.    Over time, often in as little as a couple of hours, the shortage of oxygen can cause cells to die.  Additionally, CO will impact vital organs, such as your brain and heart and cause them to shut down.

Everyone is at risk.  But pregnant women and unborn babies, children, the elderly and those with chronic heart disease are especially vulnerable to CO poisoning.  Smoke inhalation during a fire frequently causes CO poisoning.

The type of equipment or the type of fuel doesn’t matter.  Whenever something is burned, whether it’s wood, natural or LP gas, oil, kerosene, charcoal, gasoline or diesel fuel there are by-products of the combustion process.  These by-products include carbon monoxide, carbon dioxide, nitrogen oxides, sulfur dioxide, water vapor and other particulate matter.

Normally, these by-products are vented to atmosphere by a chimney system, vent pipe or exhaust system.  An improper installation or poorly maintained equipment can put your loved one’s lives in danger.


  • Vomiting or nausea
  • Headache
  • Weakness
  • Problems feeling dizzy
  • Losing coordination
  • Being confused
  • Shortness of breath
  • Blurred vision
  • Losing consciousness

These warning signs can be subtle and are often dismissed as simply not feeling well.  CO poisoning is a medical emergency.  Your health can deteriorate very quickly.  Get those affected into fresh air immediately and call 911.

Also, keep in mind that carbon monoxide poisoning is especially dangerous for people who are sleeping or have been drinking alcoholic beverages.  Irreversible brain damage, life threatening cardiac complications or death can happen, often before anyone knows there’s even a problem.


Your family is at a high risk of CO poisoning when fuel burning appliances are used improperly or are not cleaned, maintained or repaired as needed.  Remember:

  • NEVER barbecue on a charcoal, gas or pellet grill indoors without proper ventilation.  Don’t cook on a grill in a tightly sealed or an enclosed space.  By doing so, you will allow carbon monoxide levels to accumulate to dangerous levels.
  • ALWAYS use space heaters in a well-ventilated area.
  • NEVER let the connector pipe, the chimney pipe or the flue in a masonry chimney fall into disrepair.  If maintenance or repairs are needed, schedule it in spring or early summer.  Companies that specialize in this type of work get very busy in late summer and fall.  Before you build a fire in your fireplace or wood burning stove, inspect all connections on pipes and make sure all clearance requirements are met or exceeded.
  • NEVER burn wood in a fireplace with an obstructed chimney.  When a chimney is not checked and serviced routinely by a CSIA professional, creosote can form.  (LINK to: creosote and/or chimney cleaning articles??)  The chimney could be blocked.  Debris or a bird’s nest can allow dangerous combustion gases to accumulate.
  • DO NOT allow a car or truck, a lawnmower, ATV, tractor or motorcycle to idle in an enclosed garage or shed.
  • NEVER operate a portable generator in your basement or anywhere in your house.  The exhaust from a generator contains high levels of carbon monoxide.
  • DO NOT leave a gas cooking stove/oven on too long.  Never use a stove or oven to heat the house.  And, portable camping cookstoves are strictly for outdoors use.
  • ALWAYS call a certified professional to check your gas furnace before it’s turned on in the fall.  They will inspect for a cracked heat exchanger, proper venting connections or other damage to critical components.  And while they are at your house, have them inspect the gas hot water heater to insure it is venting correctly.
  • FURTHERMORE, if your home is very tight, have the certified repair people inspect your fireplace. (LINK to:  We Love Fire dealer near you?)  A fireplace, especially on the lowest level of your home could cause a reverse air flow that might draw combustion gases back into your living space.


. . . . you have soot or creosote buildup in your masonry or stainless steel chimney.

. . . . you notice loose masonry material on the roof or on the ground.

. . . . you notice a decreasing supply of hot water.

. . . . you have missing or loose furnace panels.

. . . . you see rust or water streaking on your chimney system or vent pipes.

. . . . you notice disconnected or loose connections in your chimney system or vent pipes.


The best way to keep your family safe from CO is common sense and regular maintenance.  The list below is not all inclusive, but by following these recommendations the safety of your loved ones will be protected.

  • Invest in a new carbon monoxide detector for each floor of your home. Be sure the CO detectors meet the Underwriter Laboratories (UL) safety standards.  Install them where the manufacturer suggests, usually in bedroom hallways and in the furnace or mechanical room.  CO detectors are also available for campers, motorhomes and boats.  Be sure to regularly replace the batteries.
  • Keep all fuel burning appliances and engines vented properly, including: space heaters, grills, furnaces, water heaters, wood stoves and fireplaces, generators and engines.
  • Be sure to open the damper on your wood fireplace every time you use it.
  • Operate all space heaters in a well-ventilated area.
  • Keep your wood burning fireplace or stove in good repair. Replace any worn or damaged parts.  Or, if it’s an older appliance, replace it with a top rated, highly efficient fireplace or stove.  And as the code states:  Inspect your chimney system annually and clean if necessary.
  • Store your generator outside. Use it outside.  Never inside.
  • Get in the habit of starting your vehicles with the garage door up. Be especially careful with an attached garage as the rest of the house is vulnerable to migrating CO fumes.  Never leave a car running in a garage.

Your WE LOVE FIRE expert is concerned about your safety and good health.  We want you and your family to enjoy our products and have the utmost faith in the service and repair work we offer.  Please call or email us with any other questions or if you need any additional information.

Below is a list of fireplace and grill stores that service Virginia (VA)

Manassas, VA

Winston's Chimney Service
11301 Industrial Road
Manassas, VA 20109

Winston's Chimney Service LogoVisit Store Page

Mechanicsville, VA

Hearth & Home Shoppe
8151 Mechanicsville Tpk
Mechanicsville, VA 23111

Hearth & Home Shoppe LogoVisit Store Page

Roanoke, VA

Dixie Building Products Inc.
3342 Melrose Ave NW
Roanoke, VA 24017

Warrenton, VA

Costello's Warrenton Fireplace & Hot Tub
251 West Lee Hwy
Warrenton, VA 20186

For more information, contact your local fireplace and grill store..

30 Responses

  1. Amanda
    Our wood burner is not burning stove still close to hot. We have an electrical heater plugged in a sealed oil type and our carbon monoxide alarm just went off! We opened windows but again nothing is burning...first time it has ever gone off. Any idea why? We feel fine. Wood burner had been going all day with windows open bc it's too hot. Windows all got closed at around 10PM. Wood burner still burning on low. At 2AM wood done burning and it goes off. Nothing else happening in the living room where the alarm, heater and wood burner is... any idea what cause it to go off? Thanks!!
    • We Love Fireplaces and Grills
      Hi Amanda Thanks for reaching out and for reading our blog. I would like to congratulate you for having the Carbon Monoxyde Detector installed and in use. We wish every home had one. The description of your problem would lead us to have a site visit. Your problem could be related to your chimney needing a good cleaning or maybe repair. It could also be that your home is very airtight, and we would need to supply fresh air to your fireplace. It could also be the environment around your house, like wind and nearby trees that would obstruct the air flow of your chimney. Many different factors to look into. We strongly recommend to use our ‘store finder’ feature and locate the closest one to your home. Have them come and look at your setup and they will advise you as what is best to do ( This is important, your safety and the one of your family depends on this. I hope this will help you find the solution to your issue. All the best!
  2. Mildred Bryant
    I have a wood burning fireplace that I am not using. It was in my house when I purchased it. I have an electric heater that I would like to place inside of the fireplace instead. Should have any concerns about carbon monoxide poisoning?
    • We Love Fireplaces and Grills
      Good day Mildred Thanks for your comment and for reading our blog. Electric fireplaces represent absolutely no risk with Carbon Monoxide Poisoning. You are safe that way. Simply make sure the electric fireplace is securely installed inside the fireplace and the electrical connection is made up to code. Then, you will be 100% sure your home is safe. If you need a local expert to inspect your installation, feel free to look at our network of experts using the following link: Stay warm!
  3. Chris
    We heat primarily with our Dutch West wood-burning stove. We have lived in this house for year & not that it’s relevant but it’s a big log home. We have had no issues. I did plug in an electric heater in the bathroom this morning and the car monoxide detector went off. I guess it’s a no-brainer - unplug it, don’t use it and open the windows! Are there any other concerns for my situation? thank you so much
    • We Love Fireplaces and Grills
      Good morning Chris Thanks for your comment. If you are certain about the timing of using the electric heater and triggering the CO detector, it could simply be that the electric heater had some dust to burn off or paint to cure. If the heater had a smell while heating up, it could be it. If that is the case, that should only happen once or twice. It might be worth trying it again and monitor it. If no smell was related to using the electric heater, maybe you will need to investigate further or stop using that heater. Hope this helps,
  4. Debra
    We had a regular wood burning fireplace. We do not have a door on it. When can we close the damper after we have had a fire in the fireplace? I don’t want to close it too soon but when we have a fire in the fireplace in the evening I don’t want to go to bed and leave the damper open on cold winter nights because the cold air comes down into the house.
    • We Love Fireplaces and Grills
      Good morning Debra Thanks for your comment. To answer your question, we recommend to wait until the fire is out completely before closing the damper. It means the coals are at room temperature and no trace of smoke is produced anymore. If you close the damper too soon, the smoke will go in the house and it would not be good at all. Hope this helps. Stay warm!
  5. Aimie
    Good morning. I have a vented natural gas fireplace. I know that the flue must stay open before starting the fire until you turn the gas off. My question is how long should I wait to close the flue once I turn the gas off to allow all of the harmful gases to release? I was told 30 minutes but that seems like an excessive amount of time and I do not want to look heat.
    • Aimie
      Type sorry, l don't want to lose heat.
      • We Love Fireplaces and Grills
        Dear Amy Thanks for reaching out. We totally understand the concern about loosing heat. The 30-minute reference is the safe side. After you shut off the gas, it should not take long for 'fumes' to cool down. It depends on your fireplace setting, how hot it got, etc. If you monitor the temperature of your fireplace and it gets closer to room temperature before the 30-minute mark, you may close the damper and it would be safe. Do you have a CO Detector in that room where the fireplace is? If you close your damper earlier than 30 minutes and the CO detector does not trigger, it would be the best way to make sure you are safe in this process. Hope this helps!
  6. Jason
    What is a normal CO level from the chimney of a pellet stove. Thanks
    • We Love Fireplaces and Grills
      We do not have this information. You may have to contact the pellet stove manufacturer directly. They may have it from their test reports, but it may not be pertinent to your installation and fuel.
  7. Kelly
    Hi we have just moved into a new house which has a combustion heater. We have a baby and toddler, can you please tell me any precautions with this and how to care for it. Thanks
    • We Love Fireplaces and Grills
      Hi Kelly Thanks for visiting with us. The heater you are referencing, is it a wood heater? If yes, you may want to look at our Wood Fireplace blog articles. If it is a Gas Fireplace, you may want to review our Gas Fireplace blog articles ( In all cases, you may want to also visit with our local experts. You can find one here: They can inspect your installation and tell you how to use it safely. All the best!
  8. Michelle
    Hello, We recently had a Scandia 300 Warmbrite Wood Heater installed that we are loving!~But since than, I have heard about Co2 emission dangers in the home. Thanks for your article, its really helpful! I am going to purchase the Co2 reader today. Maybe a silly question, but I was wondering how safe this type of fire place is to burn? We have a glass door on ours which we always keep on but we burn it all afternoon, as soon as we get home until we go to bed. Also, my husband thinks its safe to put another log on the fire before (which means it is burning strongly as we leave the room - and sleep at the other end of the house) bed but im not so sure and feel uncomfortable doing this. I have read it is unsafe.. Are we better to let it finish burning or even put it out before bed or is it safe, as my husband says because it has a glass door? The reason we keep it on is we have two dogs that sleep in the lounge room as we wanted them to stay warm! Im also concerned now this is ant the safest place for them to sleep if there is Co2 emissions from the fireplace.. Thanks in advance, really appreciate the advice! Michelle
    • We Love Fireplaces and Grills
      Hello Michelle I am assuming you might be from Australia? The Scandia heater you are referring to is certified. It has a sealed glass door, which means it is safe to use when the door is closed. However, I do have a question for you: Has the heater been professionally installed with an approved chimney? If this information is unknown, I would recommend you have your installation inspected by a professional. You might be able to find one via the Scandia website or via the Australia Home Heating Association. All the best!
  9. Kontaktgrill Ratgeber
    Thanks for finally talking about > How to Prevent Carbon Monoxide (CO) Poisoning - We Love Fireplaces and Grills < Loved it!
    • Katia Lavoie
      Your welcome! We are glad you loved it.
  10. Jan
    Hello, I have 2 gas log fireplaces. I have had them for four years and never had a problem with soot building up on the logs until this year. I have taken the logs off to clean off the heavy soot and now after Reading your previous comments am wondering if I placed them back wrong so causing more soot. Also my co2 detector went off last night. Both fireplaces were used for about 3 hours. And the alarm went off 3 to 4 hours after they were shut off. Also I was told by the company that installed my gas burners I would never need to have the chimney cleaned again. Any suggestions would be helpful, thank you!
    • Dominique Page
      Hello Jan Thanks for reaching out. The soot build up is certainly indicating poor combustion. That is typically due to either the wrong log placement and possibly, a lack of combustion air. (which may explain why the CO detector was triggered). The best is to get your local company who installed the burners to come in and fix it. You may look for our affiliated local expert by searching here: In the meantime, it would be best not to use your fireplaces. All the best! Dominique
  11. Mark
    Hi I have a log fire place with a glass door , what I am find is if we start the fire with hard wood we don't seem to have this problem , but if I start the fire with any other wood that is laying around to start the fire you can get a smell coming from the fireplace then it sets of the smoke alarms ,I think it's the carbon monxicde alarm in them that goes off, as you can't smell smoke or see smoke .Do you know what is cause if this or how to fix or find where it might be coming from. Most days I start the fire place aroound midnight after the fireplace coals are ready to add more wood I put on sometimes good size hard wood logs but it's no smell or problem then .
    • Dominique Page
      Hello Mark Could it be that the firewood 'laying' around is more wet? Wet wood is harder to burn, produces more smoke and less heat. This could explain why you get the smell. It can also explain why your smoke detector is triggered. On site inspection can be an option. Your local fireplace store might be able to help. Cheers!
  12. modusfireplaces
    Very informative article. Thanks a lot for sharing.
  13. Marlene Van Helden
    Hello, I have a friend who has a relatively new fire stove in her home, professionally installed. She has a habit of placing logs on top of the burning stove to warm them before she places them into the fire box to burn. As a result, the top of her stove always has a fine layer of ash on it. I am worried this habit could result in CO gases being produced while they 'slowly' heat up and while the stove is also burning logs in the fire box? (Not to mention causing a fire on top of her stove.) Looking forward to your reply, Marlene Nov. 2019
    • Dominique Page
      Hi Marlene Please tell your firend not to put any wood on top of the woodstove. This is a fire is dangerous.
  14. Amy
    We have a wood burning fireplace with glass doors that we use only several times each winter. Now that it’s getting warmer outside, we haven’t used it in months. Today I smelled a strong smell of ash, off and on throughout the day, and this afternoon our CO detector went off. I reset the alarm and it didn’t go off again, but I opened windows to be safe. Could there be a correlation between the smoky smell and the CO level? Would scheduling a cleaning be sufficient? We usually only have it cleaned every other year, and we aren’t due yet.
    • Dominique Page
      Hi Amy Thanks for your message. To answer your question: Yes, there is a potential correlation between the smell from your chimney and the CO levels. There may be other causes for the CO detector to go off too. Having the chimney serviced is good idea, and maybe getting a sealed chimney damper installed is also recommended. You may also consider glass doors on that fireplace...We had this article done a few months back, if you would like to take a look.
  15. Riley
    How long does it take for CO to become a serious threat because we do not have a CO detector, but I have mild symptoms of CO poisoning, but then again it could be phycology tricking me as I been researching why I have nausea due to fire place...
    • Dominique Page
      Hi Riley Thanks for reaching out. Don't take any chances...order a CO detector! If you are having nausea while running the fireplace, stop using it until you install the CO detector. Stay safe!!!

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