Carbon monoxide (CO) is a colorless, odorless, poisonous gas that formsfrom incomplete combustion of fuels, such as natural or liquefied petroleumgas, oil, wood or coal.
Facts and Figures
480 U.S. residents died between 2001 and 2003 from non-fire-relatedcarbon-monoxide poisoning.
Most CO exposures occur during the winter months, especially in December(including 56 deaths, and 2,157 non-fatal exposures), and in January (including69 deaths and 2,511 non-fatal exposures). The peak time of day for CO exposureis between 6 and 10 p.m.
Many experts believe that CO poisoning statistics understate the problem. Because the symptoms of CO poisoning mimic a range of common healthailments, it is likely that a large number of mild to mid-level exposures are never identified, diagnosed, or accounted for in any way in carbon monoxide statistics.
Out of all reported non-fire carbon-monoxide incidents, 89% oralmost nine out of 10 of them take place in a home.
Physiology of CarbonMonoxide Poisoning
When CO is inhaled, it displaces the oxygen that would ordinarily bind with hemoglobin, a process that effectively suffocates the body. CO can poison slowly over a period of several hours, even in low concentrations. Sensitive organs, such as the brain, heart and lungs, suffer the most from a lack of oxygen.
High concentrations of carbon monoxide can kill in less than fiveminutes. At low concentrations, it will require a longer period of time to affect the body. Exceeding the EPA concentration of 9 parts per million (ppm)for more than eight hours may have adverse health affects. The limit of COexposure for healthy workers, as prescribed by the U.S. Occupational Health and Safety Administration, is 50 ppm.
Potential Sources of Carbon Monoxide
Any fuel-burning appliances which are malfunctioning or improperlyinstalled can be a source of CO, such as:
stoves and ovens;
fireplaces and wood stoves;
clogged chimneys or flues;
power tools that run on fuel;
gas and charcoal grills;
certain types of swimming pool heaters; and
CO Detector Placement
CO detectors can monitor exposure levels, but do not place them:
directly above or beside fuel-burning appliances, as appliances may emita small amount of carbon monoxide upon start-up;
within 15 feet of heating and cooking appliances, or in ornear very humid areas, such as bathrooms;
within 5 feet of kitchen stoves and ovens, or near areas locations where household chemicals and bleach are stored (store such chemicals away from bathrooms and kitchens, whenever possible);
in garages, kitchens, furnace rooms, or in any extremely dusty, dirty,humid, or greasy areas;
in direct sunlight, or in areas subjected to temperature extremes. Theseinclude unconditioned crawlspaces, unfinished attics, un-insulated or poorly insulated ceilings, and porches;
in turbulent air near ceiling fans, heat vents, air conditioners,fresh-air returns, or open windows. Blowing air may prevent carbon monoxide from reaching the CO sensors.
Do place CO detectors:
within 10 feet of each bedroom door and near all sleeping areas, whereit can wake sleepers. The Consumer Product Safety Commission (CPSC) and Underwriters Laboratories (UL) recommend that every home have at least one carbon monoxide detector for each floor of the home, and within hearing range of each sleeping area;
on every floor of your home, including the basement (source: International Association of Fire Chiefs/IAFC);
[near or over any attached garage. Carbon monoxide detectors are affectedby excessive humidity and by close proximity to gas stoves (source: Cityof New York);
near, but not directly above, combustion appliances, such as furnaces,water heaters, and fireplaces, and in the garage (source: UL);and
on the ceiling in the same room as permanently installed fuel-burning appliances, and centrally located on every habitable level, and in every HVACzone of the building (source: National Fire ProtectionAssociation 720). This rule applies to commercial buildings.
In North America,some national, state and local municipalities require installation of COdetectors in new and existing homes, as well as commercial businesses, among them: Illinois, Massachusetts, Minnesota, New Jersey, Vermont and NewYork City, and the Canadian province of Ontario. Installers are encouraged tocheck with their local municipality to determine what specific requirements have been enacted in their jurisdiction.
How can I prevent CO poisoning?
Purchase and install carbon monoxide detectors with labels showing that they meet the requirements of the new UL standard 2034 or Comprehensive SafetyAnalysis 6.19 safety standards.
[Make sure appliances are installed and operated according to themanufacturer's instructions and local building codes. Have the heating system professionally inspected by a Home Inspector inspector and serviced annually to ensure properoperation. The inspector should also check chimneys and flues for blockages,corrosion, partial and complete disconnections, and loose connections.
Never service fuel-burning appliances without the proper knowledge,skill and tools. Always refer to the owner's manual when performing minor adjustments and when servicing fuel-burning equipment.
Never operate a portable generator or any other gasoline engine-poweredtool either in or near an enclosed space, such as a garage, house or other building. Even with open doors and windows, these spaces can trap CO and allow it to quickly build to lethal levels.
Never use portable fuel-burning camping equipment inside a home, garage,vehicle or tent unless it is specifically designed for use in an enclosed space and provides instructions for safe use in an enclosed area.
Never burn charcoal inside a home, garage, vehicle or tent.
Never leave a car running in an attached garage, even with the garagedoor open.
Never use gas appliances, such as ranges, ovens or clothes dryers to heat your home.
Never operate un-vented fuel-burning appliances in any room where peopleare sleeping.
During home renovations, ensure that appliance vents and chimneys arenot blocked by tarps or debris. Make sure appliances are in proper working order when renovations are complete.
Do not place generators in the garage or close to the home. People lose power in their homes and get so excited about using their gas-powered generator that they don't pay attention to where it is placed. The owner's manual should explain how far the generator should be from the home.
Clean the chimney. Open the hatch at the bottom of the chimney toremove the ashes. Hire a chimney sweep annually.
Check vents. Regularly inspect your home's external vents to ensure theyare not obscured by debris, dirt or snow.
In summary, carbon monoxide is a dangerous poison that can be created byvarious household appliances. CO detectors must be placed strategically throughout the home or business in order to alert occupants of high levels ofthe gas.