2010-01-14 / Features

Carbon Monoxide, The Silent Killer

Public information and safety tips

Each year, nearly 5,000 people in the United States are treated in hospital emergency rooms for carbon monoxide (CO) poisoning. This number is, however, believed to be an underestimate of those poisoned because many people exhibiting the symptoms of CO poisoning mistake these symptoms for the flu or are misdiagnosed.

Why is CO the silent cold weather killer?

CO is a colorless, odorless, toxic gas. It is produced by the incomplete combustion of solid, liquid, or gaseous fuels. Appliances fueled with gas, oil, kerosene, or wood may produce CO. If such appliances are not installed, maintained and used properly, CO may accumulate to dangerous and even fatal levels in cars, homes or poorly ventilated areas.

CO poisoning can kill without warning as your family sleeps. Because CO gas has no odorwarning properties even at toxic or life threatening levels, it is considered a silent killer. And, since so many deaths occur as the result of defective or poorly operated home heating devices, CO has been termed the “silent, cold weather killer.”

Where Does CO come from?

CO is produced by products that burn fuels. Therefore, any fuel-burning appliance in your home is a potential CO source. Electrical heaters and electric water heaters, toasters, etc., do not produce CO because they don’t involve combustion of fuels. Under normal circumstances, CO levels in the typical home or workplace should not be above levels found outdoors.

When appliances are kept in good working condition and are properly vented, they produce little CO. Improper installation, operation, or poorly vented appliances can produce elevated – or even fatal – CO concentrations in your home. Likewise, using kerosene heaters or charcoal grills indoors or running a car in a garage can cause levels high enough to result in CO poisoning.

Common sources of CO include the following:

Room heaters (not radiant or electric)

Furnaces Charcoal grills Cooking ranges (not electric)

Water heaters (not electric)

Automobiles run in closed garages


Portable generators

Wood-burning stoves

Who is at risk of CO poisoning?

Any person or animal in a space shared with a device capable of generating CO should be considered at risk of CO poisoning. CO exposures especially affect unborn babies, infants and people with anemia or a history of heart disease. Breathing low levels of the chemical can cause fatigue and increase chest pain in people with chronic heart disease.

Although not always experienced, the initial symptoms of CO poisoning are similar to the flu, but without the fever. They include:

Dizziness Fatigue Headache Nausea

Irregular Breathing

It is critical to note that death from CO poisoning can occur quickly or when sleeping, with some or all of these symptoms never being experienced, in which case, the overexposed victim becomes unconscious and never regains consciousness.

How can CO poisoning be prevented?

Dangerous levels of CO can be prevented by proper appliance installation, maintenance, and use. Periodic inspections of potentially CO-producing equipment, and the use of CO alarms, are also key to avoiding a CO fatality.

You can learn more about industrial hygiene and protecting yourself from CO poisoning by visiting www.aiha.org. A consultants listing of industrial hygienists that includes specialists in CO poisoning is available on the site. AIHA can make available experts on this topic to interview. To arrange for an interview, please contact Alexandra Walsh at 301-523-3318 or awalsh@ associationvision.com.

Founded in 1939, the American Industrial Hygiene Association (AIHA) is the premier association of occupational and environmental health and safety professionals. AIHA’s members play a crucial role on the front line of worker health and safety every day. Members represent a cross-section of industry, private business, labor, government and academia. For more information, go to www.aiha.org.

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