Carbon monoxide (CO) is a deadly gas that Houseinhibits oxygen intake. Carbon monoxide is odorless, tasteless, and colorless, which makes it very difficult to detect while going about daily life. In part, this is why carbon monoxide poisoning is such a serious issue, as it can quickly become fatal before anyone being exposed realizes there is any problem at all. In fact, carbon monoxide poisoning is among the leading causes of fatal poisoning worldwide in industrialized countries. Every homeowner needs to be concerned about the quality of air inside their home, and at the top of the list should be carbon monoxide. It is important to know what causes carbon monoxide in homes and what preventive and corrective measures can be taken to stop it from building up. Fortunately, with the right precautions and knowledge this doesn’t have to be difficult or a chore, and carbon monoxide poisoning doesn’t have to be a significant risk for you or your family.

Common Sources of Carbon Monoxide in Houses 

Carbon monoxide is a result or by-product of combustion. In the home, common sources of carbon monoxide include:

  • Malfunctioning furnaces, heaters, and wood burning stoves
  • Fireplaces
  • Improperly vented electrical generators (diesel, gasoline)
  • Propane powered drying machines, kitchen stoves, and portable stoves
  • Charcoal grills
  • Automobile exhaust, pressure washers, lawn equipment (for attached garages)

Any appliances that could potentially cause a problem need to be properly maintained, which includes regular inspections, adjustments, and servicing by trained professionals. Of course, this would be a good idea for other reasons even if one wasn’t concerned about the air quality inside their house.

Symptoms of Carbon Monoxide Poisoning

Many of the early symptoms of carbon monoxide poisoning can be easily and often are mistaken for the flu or other common illnesses. It is also important to note that individuals can react quite differently to the same concentrations of CO in the air. Individuals with certain illnesses such as asthma or emphysema can have significantly lower tolerance levels. Initial symptoms can include but are not limited to:

  • Headaches and dizziness
  • A feeling of tightness in the chest
  • Fatigue
  • Nausea
  • Increased heart rate

Later stage symptoms can include:

  • Confusion
  • Vomiting
  • Difficulty with coordination
  • Loss of consciousness

CO Concentration Levels

CO levels in parts per million (ppm)

Health Effects


Normal levels inside a house


Maximum recommended exposure over twenty-four hours


Maximum recommended exposure for one hour


Initial symptoms begin to appear


Severe symptoms in under an hour, death within two to three hours


Death within one hour


Death within a few minutes

In many cases, the effects of CO poisoning can be reversed, but in severe cases the effects can be permanent. The heart and brain are at particular risk for permanent damage as they require high levels of oxygen. If you suspect you or someone else is experiencing or at risk of CO poisoning, it is vital that you move to an area not affected immediately.

Carbon Monoxide Detectors in the Home

To protect yourself against CO poisoning it is important that you not only make sure that your home and appliances are in good working condition, but that you have carbon monoxide detectors in place to warn you of any danger. As with smoke detectors, you should have CO detectors placed on every level of the home and near sleeping quarters. However, CO detectors do not need to be placed on the ceiling or at ceiling level like smoke detectors. Depending on the size of your home and the layout, it is worth considering placing CO detectors near the main sources of carbon monoxide leaks, such as furnaces, particularly if they are in confined spaces.

Even if carbon monoxide levels are not at sufficient concentrations to be noticed or fatal, long term low level exposure to CO comes with a variety of serious health risks. This can include memory loss, depression, and possibly permanent neurological damage. With the relatively low cost of CO detectors, there is no reason not to have them and the peace of mind that comes from knowing there is nothing causing carbon monoxide to buildup in your home.