• What is carbon monoxide (CO) and why do I need a carbon monoxide detector?

Carbon monoxide is a colorless, odorless, tasteless and toxic gas produced as a by-product of combustion. Any fuel burning appliance, vehicle, tool or other device has the potential to produce dangerous levels of carbon monoxide gas. Examples of carbon monoxide producing devices commonly in use around the home include:

• Fuel fired furnaces (non-electric)
• Gas water heaters
• Fireplaces and woodstoves
• Gas stoves
• Gas dryers
• Charcoal grills
• Lawnmowers, snowblowers and other yard equipment
• Automobiles

The Consumer Products Safety Commission (CPSC) reports that approximately 200 people per year are killed by accidental CO poisoning with an additional 5000 people injured. These deaths and injuries are typically caused by improperly used or malfunctioning equipment aggravated by improvements in building construction which limit the amount of fresh air flowing in to homes and other structures.

While regular maintenance and inspection of gas burning equipment in the home can minimize the potential for exposure to CO gas, the possibility for some type of sudden failure resulting in a potentially life threatening build up of gas always exists.

• What are the medical effects of carbon monoxide and how do I recognize them?

Carbon monoxide inhibits the blood's ability to carry oxygen to body tissues including vital organs such as the heart and brain. When CO is inhaled, it combines with the oxygen carrying hemoglobin of the blood to form carboxyhemoglobin. Once combined with the hemoglobin, that hemoglobin is no longer available for transporting oxygen. How quickly the carboxyhemoglobin builds up is a factor of the concentration of the gas being inhaled (measured in parts per million or PPM) and the duration of the exposure. Compounding the effects of the exposure is the long half-life of carboxyhemoglobin in the blood. Half-life is a measure of how quickly levels return to normal. The half-life of carboxyhemoglobin is approximately 5 hours. This means that for a given exposure level, it will take about 5 hours for the level of carboxyhemoglobin in the blood to drop to half its current level after the exposure is terminated.

The following table describes the symptoms associated with a given concentration of COHb:

% COHb	Symptoms and Medical Consequences
10%	No symptoms. Heavy smokers can have as much as 9% COHb.
15%	Mild headache.
25%	Nausea and serious headache.  Fairly quick recovery after                   treatment with oxygen and/or fresh air.
30%	Symptoms intensify.  Potential for long term effects                        especially in the case of infants, children, the elderly,                   victims of heart disease and pregnant women.
45%	Unconsciousness.
50%+	Death.

IF YOUR CARBON DIOXIDE DETECTOR ACTIVATES, CALL 911 IMMEDIATELY