Carbon monoxide (CO) has been called the invisible killer because it is a colorless, odorless, tasteless, toxic gas. According to the Centers for Disease Control, 15,000 people per year are treated for carbon monoxide poisoning in the U.S., and approximately 500 of these poisonings result in death.

Occasionally, we hear of a person or family killed or injured by carbon monoxide poisoning from a faulty furnace or other gas-burning appliance. In most cases, these deaths and injuries could be prevented by installing CO detectors. In spite of this simple solution, there are no requirements in the building codes for CO alarms in homes. And tragically, this oversight is ignored by most municipal building departments.

Most people have heard of carbon monoxide, but few know what it is. CO is a deadly gas produced when fuel is partially burned. Fuel that is completely burned produces carbon dioxide and steam, both of which are safe to breathe. So what’s the difference between carbon dioxide and carbon monoxide? The answer lies in their molecular structures. A carbon dioxide molecule contains one atom of carbon and two atoms of oxygen. When carbon is partially burned, the result is a molecule with only one atom of oxygen.

When we inhale carbon monoxide, our respiratory systems mistake CO molecules for oxygen molecules, allowing them to attach to our red blood cells. Each blood cell that carries a CO molecule is effectively out of business. It can no longer serve its intended function to carry oxygen to the brain and other organs. As our bodies receive less and less oxygen, damages leading to death begin to occur. Those who survive CO poisoning are sometimes permanently disabled due to brain damage.

The immediate symptoms of CO poisoning include headache, nausea, dizziness, fatigue and shortness of breath. Unfortunately, these are similar to flu symptoms and can therefore be misdiagnosed by doctors. In such cases, victims may return home to further CO exposure.

The most common sources of CO in homes are faulty fuel-burning fixtures such as furnaces, water heaters, kitchen ranges, fireplaces and room heaters. Other sources include vehicles left idling in garages or charcoal that is burned indoors or in tents or campers.

Most people are familiar with smoke alarms. For more than 30 years, the code requirements for smoke alarms in homes have become increasingly strict, and with good cause. At the same time, nothing has been done to address the hazards of carbon monoxide exposure, in spite of equally good cause.

The authors of the various building and safety codes have apparently ignored this significant health and safety hazard, notwithstanding the availability of reasonably priced CO detectors. Meanwhile, most municipal building departments show no interest in addressing the situation by enacting requirements of their own.

Rather than wait for local building officials to establish a safety requirement, homeowners and landlords should purchase CO alarms and install them in all dwellings. Most hardware stores sell an assortment of CO detectors. In fact, the two major brands of smoke alarms produce fixtures that detect both smoke and carbon monoxide. These can be placed in the same locations as regular smoke alarms — near bedrooms, in bedrooms, on high ceilings and in basements.

The price of CO exposure is ultimately high, while the cost of prevention is low. So be proactive. Protect yourself and your family from the invisible killer.

To write to Barry Stone, please visit him on the Web at


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