Carbon monoxide (CO) is a colorless, odorless, and tasteless gas formed during combustion. It is highly poisonous and can be deadly when inhaled. CO is a byproduct of burning various fuels, including wood, natural gas, coal, and kerosene.
How Carbon Monoxide Forms During Wood Burning
Carbon monoxide is produced during the incomplete burning of organic matter, such as wood. When insufficient oxygen is available for complete combustion, carbon in the fuel combines with less oxygen, forming CO instead of carbon dioxide (CO2).
Several factors contribute to incomplete combustion when burning wood. Insufficient oxygen supply to the fire is a primary cause, which can happen if a wood-burning appliance is in a poorly ventilated area. Burning wet or unseasoned wood also increases CO production, as the moisture hinders efficient combustion. A blocked chimney or flue also prevents proper ventilation, trapping combustion byproducts like CO inside the home.
A malfunctioning wood-burning stove or fireplace can also lead to dangerous CO buildup. Issues like damaged flue liners or improperly installed systems can allow the gas to seep into living spaces.
Understanding Carbon Monoxide Exposure
Carbon monoxide harms the body by interfering with oxygen delivery. When inhaled, CO binds to hemoglobin in red blood cells more readily than oxygen, forming carboxyhemoglobin. This prevents red blood cells from carrying the necessary oxygen to organs and tissues, particularly affecting the brain and heart.
Symptoms of CO poisoning can be mistaken for the flu, including headache, dizziness, nausea, and fatigue. Other symptoms are weakness, shortness of breath, confusion, and chest pain. The severity of symptoms depends on the level and duration of exposure.
Higher concentrations or prolonged exposure to CO can lead to more severe outcomes, such as loss of consciousness, seizures, arrhythmias, or even death. Even low-level exposure over time may result in persistent headaches, memory issues, or heart problems. Pregnant individuals, infants, children, older adults, and those with heart or lung conditions are at greater risk from CO exposure.
Ensuring Safe Wood Burning Practices
Ensuring safe wood burning involves several proactive measures. Adequate ventilation is fundamental; ensure your wood-burning appliance is installed in a well-ventilated area with fresh air intake. Keeping the appliance’s damper open and doors closed during operation helps maintain efficient combustion and prevents harmful chemicals from escaping into the home.
Using dry, seasoned wood is crucial for cleaner and more efficient burning. Seasoned wood has a moisture content of less than 20 percent and produces less smoke and CO. Avoid burning treated wood, trash, or other materials that can release toxic chemicals or damage your appliance.
Regular maintenance of wood-burning appliances and chimneys is also important. Cleaning the stove and flue system prevents creosote buildup, a flammable substance that can contribute to CO emissions and chimney fires. Annual professional inspections and cleaning of chimneys and flues help ensure they are free from blockages and operating correctly.
Carbon Monoxide Detection and Emergency Response
Since carbon monoxide is undetectable by human senses, installing CO detectors is a crucial safety measure. These alarms detect the gas and alert occupants. For comprehensive protection, install detectors on every level of the home, especially near sleeping areas and on any level with fuel-burning appliances.
Residential CO alarms should meet safety standards like ANSI/UL 2034. Regular testing of CO detectors, typically by pressing a test button monthly, ensures they are functioning correctly. Batteries in battery-operated units should be replaced every six months, and the entire detector unit typically needs replacement every 5 to 7 years.
If a carbon monoxide alarm sounds or if symptoms of CO poisoning are suspected, immediate action is necessary. Evacuate everyone from the building to fresh air immediately and call emergency services. Do not re-enter the home until emergency personnel confirm it is safe to do so.