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Sources CO



Carbon Monoxide (CO) is an odorless, colorless and tasteless, yet deadly gas. It is important to understand what causes it in your home so you can protect your family from the dangers of carbon monoxide poisoning.




There are many precautions you can take that will help your family avoid dangerous exposure to carbon monoxide. Click on any of the potential carbon monoxide sources in the house pictured below to read safety tips on how to stop carbon monoxide from invading your home.

Click on a specific area or appliance on the house...

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If you suspect that CO is contaminating your home, the first thing you should do is to ventilate the area by opening all the windows. If you or a member of your family displays sudden flu-like symptoms, immediately evacuate your home and call the Gas Company, Oil Company, or fire department from a neighbor's house.

 



A UL listed carbon monoxide detector or CO alarm is the best protection from the deadly dangers of carbon monoxide poisoning. Make sure that the CO detector or CO alarm you use has been fully approved for its intended use. For example, do not use home-use CO alarms in boats or recreational vehicles, or garages as you may not be fully protected from the dangers of carbon monoxide.

Never unplug or remove the battery to silence a CO detector or CO alarm. You may go back to sleep and suffer the deadly consequences of carbon monoxide poisoning. At the very least, ventilate the area and change the detector's battery. Always assume the worst for your own safety.
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A chimney that is blocked or clogged due to a bird's nest, leaves, or soot can cause combustion by-products, including carbon monoxide, to vent into your home. Cracked masonry could also cause a blockage. Periodic inspection and cleaning by a chimney sweep helps prevent these problems. A screen cap for the top of the chimney to discourage nest building is also a good idea.
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Wood burning and gas-powered fireplaces are a common source of carbon monoxide in the home. Leaving the window open a few inches allows the circulation of fresh air in the room while preventing negative pressure build-up / backdrafting, which can draw carbon monoxide and other toxins into the home. Never use treated woods, painted wood, and scrap lumber in your wood burning fireplace. Only burn seasoned firewood made for that purpose. Additionally, before you start a fire in your fireplace, make sure that the damper is open and always leave the flue open even if the fire is almost out. Those last smoldering embers produce a high concentration of deadly carbon monoxide.

Gas log sets: Gas logs or burners produce a lot of carbon monoxide since the less-efficient, yellow flames are designed to create a cozy atmosphere. If you own a ventless fireplace be particularly careful since this type of appliance vents all combustion by-products into the room. As the fireplace is run, oxygen is taken from the room to fuel the combustion process. As less oxygen is available, the combustion becomes less efficient and more CO is produced. Some gas log sets use a sensor that shuts down the appliance if oxygen drops to a certain level. The main danger is that the appliance can produce CO even if the oxygen isn't depleted from the immediate environment. It is always a good idea to look for an appliance with a CO safety shut-off device.
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A furnace can produce carbon monoxide because of a mechanical failure or as the result of a cracked heat exchanger, flue or burner problems. Incorrect installation, damage caused by basement flooding, and even pilot lights can produce CO. A clogged or dirty burner can affect the air/fuel mixture resulting in inefficient combustion. Yellow flames and soot accumulation are indications that the furnace needs immediate maintenance. Frequent inspection and regular maintenance of the burner, flue, and chimney should greatly reduce any CO difficulties with your appliance.
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Ventless space heaters are so dangerous that some states including California, Colorado, Massachusetts, Minnesota, Montana, New York, Utah and Washington now prohibit their use. Some of these heaters use a sensor that shuts down the appliance if oxygen levels drop too low. The danger is the appliance can produce carbon monoxide even if the oxygen isn't depleted from the immediate environment. Never use a heater inside a house or an enclosed structure if the operating instructions tell you not to. Portable heaters and all other un-vented appliances vent all the combustion products directly into the interior of the home, so it is a good idea to look for appliances with CO safety shut-off devices. Always leave the window cracked a few inches to allow for the circulation of fresh air into the house if you use a portable heater.
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Gas stoves and range tops are common sources of carbon monoxide in a house since they are rarely vented. Regularly cleaning the range top, oven cavity and burners will alleviate the possibility of CO emissions. If the burners are dirty and clogged, the fuel air mixture becomes improperly adjusted and causes inefficient combustion. Improper installation, a defective appliance or older appliances with rust or damage to the burner system may also cause the production of CO. Keep in mind the exhaust fan located over the range top is usually un-vented and does not help discharge CO outside the home. The fan only provides filtration of grease vapor and soot generated during cooking. The best way to avoid the production of carbon monoxide is to have regular maintenance performed, including cleaning and adjustment of the air/fuel mixture. Also, never warm your house using your natural gas or propane oven.
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A water heater is another potential source of carbon monoxide. The appliance may be faulty when purchased or installed improperly. Basement flooding may cause the heater to function inefficiently. A clogged burner, blocked vent or even the pilot light can all produce carbon monoxide. Danger signs include a yellow burner flame and soot build-up. Regular appliance maintenance to ensure air/fuel mixture is adjusted correctly and cleaning of the burner components is recommended to ensure your protection against carbon monoxide poisoning.
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A gas clothes dryer that is purchased faulty or installed incorrectly can be a carbon monoxide poisoning hazard. Damage caused by flooding and exhaust pipes clogged with lint could also cause CO to build up. The burner can become dirty or clogged and affect the air/fuel mixture resulting in inefficient combustion and the production of carbon monoxide. Frequent inspection and regular maintenance of the burner are good preventive measures. Remember to clean the lint filter after every load of laundry to keep your outside vent clear.
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Grills, barbecues and hibachis should never be used indoors, or even inside the garage or on a porch or patio. The smoldering embers of charcoal produce great amounts of carbon monoxide. Always take care to grill a fair distance away from the windows of your house and keep those windows closed.
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One of the greatest risk of carbon monoxide poisoning is your home is to leave your car running in an attached garage, especially if the garage door is closed.

 

If you are camping never bring a combustion device inside an RV or tents. Campers have been killed bringing portable gas lights and cooking equipment into their RV or tent. In one case, two Swiss Campers were killed near Pike’s Peak when they used a portable gas lamp to read in their tent. Gas lamps and other combustion devices can be very dangerous at high altitude because they make much more CO. Even a car will make much more CO at high altitude.
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Insulation does reduce heat loss and keeps your energy bills down but they also decrease your fresh air supply in your home, making combustion less efficient and increasing your risk of carbon monoxide poisoning. Creating an energy-efficient home could create a negative pressure and cause a backdrafting effect that draws fumes into your home instead of exhausting them to the exterior. All fuel-burning appliances need to be in good working condition and exhausted to the exterior. Make sure there is adequate fresh air in your home at all times for efficient combustion to take place. Crack your windows or doors throughout the day. Consider saving a life more important than saving a few dollars on your energy bill.
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