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WHAT IS "CO" AND WHO IS AT RISK?

Carbon monoxide (CO) is a colorless, odorless, deadly gas. Because you can't see, taste, or smell it, carbon monoxide can kill you before you know it's there.
Everyone is at risk for carbon monoxide poisoning. Medical experts believe, however, that individuals with greater oxygen requirements such as unborn babies, infants, children, senior citizens, and people with coronary or respiratory problems are at greater risk.

WHY IS CARBON MONOXIDE SO DANGEROUS?

Carboxyhemoglobin causes symptoms similar to the flu, such as headaches, fatigue, nausea, dizzy spells, confusion, and irritability. As levels of COHb increase, vomiting, loss of consciousness, and eventually brain damage or death can result.

Source: Journal of American Medical Association

WHERE DOES CARBON MONOXIDE COME FROM?

All of these sources can contribute to a CO problem in the home. If a home is vented properly and is free from appliance malfunctions, air pressure fluctuations, or airway venting, or chimney blockages, carbon monoxide will most likely be safely vented to the outside. But energy-efficient insulation meant to keep warm air in during winter months and cool air in during summer months could cause carbon monoxide to be trapped inside.

Furnace heat exchangers can crack, vents and chimneys can become blocked, disconnected, or corroded; inadequate air supply of combustion appliances can cause conditions known as down drafting or reverse stacking, which force CO contaminated air back into the home.

WHERE TO LOOK FOR POTENTIAL SOURCES OF CO

An improperly installed or malfunctioning force air furnace could be the source of CO and should be carefully inspected by a professional.

• Measure the concentration of CO in the flue gases
  • Testing equipment used to measure the presence of carbon monoxide in the air must be calibrated to sense low levels of CO concentration.
    • Testing equipment should be capable of sensing levels as low as one part per million. For example, Underwriters Laboratories' standard for residential carbon monoxide detectors requires detectors to alarm before 90 minutes of exposure to 100 parts per million of carbon monoxide
    • If initial readings don't reveal sufficient concentrations of carbon monoxide to set off the alarm, digital measurement testing equipment that produces a printed 24-hour record can be used to help identify the source
  • If doors or windows are left open, or appliances are turned off, and outside air enters the home, carbon monoxide can dissipate. This creates a lower reading than the level that triggered the alarm.
  • To help assure proper measurement, carbon monoxide readings should be conducted as soon as possible after an alarm incident
• Check furnace connections to flue pipes, chimneys, and venting systems to outside of the home for signs of corrosion, blockages, rust, gaps, or holes
• Check furnace filters and filtering systems for dirt or blockages
• Check forced air fans for proper installations and correct air flow of flue gases. Improper furnace blower installation can result in carbon monoxide build-up because toxic gas is blown into, rather than out of the house
• Check the combustion chamber and internal heat exchanger for cracks, metal fatigue or corrosion - be sure they are clean and free of debris
• Check burners and ignition system. A flame that is mostly yellow in color in natural gas-fired furnaces is often a sign fuel is not burning completely, and higher levels of carbon monoxide are being released. Remember, you can't smell carbon monoxide.
• Check all venting systems to the outside, including flues and chimneys for cracks, corrosion, holes debris, or blockages. Animals and birds can build nests in chimneys, preventing gases from escaping.
• Check all other appliances that use flammable fuels such as natural gas, oil, wood, propane, coal, or kerosene.
  • Appliances include: gas water heaters, clothes dryers, kitchen ranges, ovens or cooktops, wood or coal burning stoves, gas refrigerators, or pressure washing machines, or generators
  • Pilot lights can be a source of carbon monoxide because the by-products of combustion are released inside the home rather than vented to the outside. Gas ovens and ranges should be monitored closely and kept in good working order. Stove tops or ovens that operate on flammable fuels should never be used to heat a residence
• Be sure space heaters are vented properly. Unvented space heaters that use flammable fuel can release carbon monoxide into the home.
• Check fireplaces for closed, blocked or bent flues, soot, and debris. When operating a fireplace and a furnace at the same time, experts recommend opening a window a crack to equalize the pressure so the combustion gasses can flow freely up and out the chimney.
• Check the clothes dryer vent opening outside the house to be sure it's free of any blockage such as lint or debris.

HOW CAN I PROTECT MYSELF AND MY FAMILY FROM CARBON MONOXIDE POISONING?

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