Risk of Carbon Monoxide Poisoning In Home
Carbon monoxide (CO), a poisonous gas that is both colorless and odorless, generates from incomplete combustion of certain fuels, such as coal, wood, oil, or petroleumgas (natural or liquefied).
Statistics
- Between the years 2001 and 2003, 480 US residents died from carbon monoxide poisoning (non-fire-related).
- Most carbon monoxide exposures happen during the winter months, particularly in December, which saw 2,157 non-fatal exposures and 56 deaths, and in January, which saw2, 511 non-fatal exposures and 69 deaths.
- Between the hours of 6 and 10 p.m. are the peak hours for carbon monoxide exposure.
- It is the belief of many experts that the statistics for carbon monoxide poisoningdo not effectively state the problem. Since the symptoms of CO poisoning are quite similar to a variety of everyday health ailments, it is highly likely that a significant number of mild to mid-level CO exposures are never actually identified, and therefore not diagnosed or accounted for statistically in any way.
- 89%(nearly 9 out of 10) of all non-fire-related CO incidents occur in a home.
The Physiology of CO Poisoning
Carbon monoxide, when inhaled, displaces the oxygen that would normally bind with hemoglobin, effectively suffocating the body. Even in low concentrations, CO can poison over a period of only several hours. Sensitive organs, particularly the lungs, brain, and heart, are affected the most significantly from a lack of oxygen.
Highly concentrated, carbon monoxide can cause death in less than five minutes. In lower concentrations, it requires a greater amount of time to cause damage to the body. Exposure for more than 8 hours to concentrations in excess of 9 parts per million (ppm) may have seriously detrimental health affects. For a worker in good health, the limit of exposure to carbon monoxideis 50 ppm,as stated by the U.S. Occupational Health and Safety Administration.
Possible Sources of Carbon Monoxide
Any appliance which burns fuel and is either malfunctioning or was not installed properly can generate carbon monoxide.This can include:
- Automobiles
- Boat engines
- Dryers
- Furnaces
- Water heaters
- Room and space heaters
- Stoves and ovens
- Fireplaces
- Wood stoves
- Charcoal grills
- Space heaters
- Clogged chimneys or flues
- Fuel-powered tools
- Certain types of swimming pool heaters
- Charcoal and gas grills
| PPM | % CO in Air | Health Effects in Healthy Adults | Source/Comments |
|---|---|---|---|
| 0 | 0% | No effects. This is the normal level in a properly functioning appliance | |
| 35 | .0035% | Maximumpermissible exposure limit in the workplace for an eight-hour shift | The National Institute for Occupational Safety and Health (NIOSH) |
| 50 | .005% | Maximumpermissible exposure limit in the workplace for an eight-hour shift | OSHA |
| 100 | .01% | Mild headache, shortness of breath, fatigue, and errors in judgment occur. | |
| 125 | .0125% | Workplace alarm must sound (OSHA). | |
| 200 | .02% | Headache, fatigue, dizziness, and nausea are present. | |
| 400 | .04% | Severe headache, dizziness, nausea, fatigue, and confusion develop. This situation can be life-threatening after three hours of exposure. | Evacuate area immediately. |
| 800 | .08% | Convulsions and loss of consciousness occur, resulting in death within three hours. | Evacuate area immediately. |
| 12,000 | 1.2% | Nearly instant death occurs. |
Guidelines For Carbon Monoxide Detector Placement
CO detectors are effective in the monitoring exposure levels, but should not be placed:
- Directly beside or above fuel-burning appliances, as these appliances, upon start-up, may release an insignificant, yet detectable, amount of carbon monoxide;
- Within 15 feet of cooking or heating appliances;
- In or around excessively humid areas, such as steam rooms or bathrooms;
- Within 5 feet of a kitchen stove or oven;
- Near locations where bleach and other household chemicals are stored (it is advisable, whenever possible, to keep chemicals such as these away from kitchens and bathrooms);
- In kitchens, garages, furnace rooms, or in any areas that are extremely dirty, dusty, greasy, or humid;
- Inplaces subject to direct sunlight or in areas that experience extreme temperatures. These include porches, unfinished attics, unconditioned crawlspaces, un-insulated or poorly insulated ceilings;
- Nearopen windows, ceiling fans, air conditioners, heat vents, fresh-air returns. Turbulent, blowing air can keep carbon monoxide from reaching the CO sensors.
Do place CO detectors:
- Within 10 feet of the door to each bedroom and in close proximity to all sleeping areas, where it can awaken sleepers. The Underwriters Laboratories (UL) and Consumer Product Safety Commission (CPSC) advise that all homesshould have at least one CO detector on each floor of the dwelling, and within audible range of all sleeping areas;
- On each and every level of your house, including the basement (source: International Association of Fire Chiefs/IAFC);
- In close proximity to or directly over any attached garage. Carbon monoxide detectors are affected by nearness to gas stoves, as well as by excessive humidity (source: City of New York);
- Close to (although not directly above)furnaces, water heaters, fireplaces, and other combustion appliances, as well as inside the garage (source: UL);
- On the ceiling of any room in whichfuel-burning appliances are permanently installed;
- In central locations on all habitable levels and in all HVAC zones of the building (source: National Fire Protection Association 720). This is a rulethat pertains to commercial buildings.
Throughout North America, many municipalities on the local, state, and national levels require the installation of CO detectors in all new and existing homes, as well as in commercial business structures, among them areNew Jersey, Massachusetts, Illinois, Minnesota, Vermont, New York City, and Ontario. Installers are encouraged to inquire with their local municipality in order to determine exactly what specific requirements exist in their area.
What Can I Do to Prevent CO Poisoning?
- Install carbon monoxide detectors with labels confirming that they comply with the requirements of the new UL standard 2034 or with thesafety standards of the Comprehensive Safety Analysis 6.19.
- Ensure that appliances are properly installed and are being operated in accordance with the manufacturer's instructions, as well as with local building codes. Have a professional heating system inspection performed by an Inter NACHI inspector, and have it serviced annually to ensure that it continues to function properly. The inspector should also check for blockages of chimneys and flues, disconnections (partial or complete), loose connections, and corrosion.
- Never attempt to service fuel-burning appliances if you are not in possession of the proper knowledge, skill, and tools to do so. Always refer to the appliance’s owner's manual when servicing or making minor adjustments to fuel-burning equipment.
- At no time should you operate any gasoline engine-powered tool or portable generator either in or near an enclosed space, such as a garage, house, or other building. These areas can trap carbon monoxide, allowing it to quickly build to lethal levels, even with windows and doors left open.
- Never use fuel-burning camping equipment inside a garage, vehicle, home, or tent unless it is designed specifically for use in an enclosed area and provides instructions for its safe operation in such areas.
- Never light and burn charcoal inside a garage,home, tent, or vehicle.
- Under no circumstancesallow a car to run in an attached garage, even with the door of the garage open.
- Do not use gas appliances, such as ranges, clothes dryers, or ovens, to heat your home.
- Never operate unvented fuel-burning appliances in any area in which people are sleeping.
- During any renovations of the home, be certain that chimneys and appliance vents are not obstructed by debris or tarps. Make sure that all appliances are properly functioning when renovations are completed.
- Never place generators close to the home or in the garage. Often, in the midst of the confusion of power outages, people fail to pay attention to where the generator is placed. Check your owner's manual for clarification as to how far the generator should be placed from the home.
- Maintain the chimney. Open the door the bottom of the chimney to remove any ashes. Schedule an annual service call with a professional chimney sweep.
- Check your vents. On a regular basis, inspect the external vents of your home to be sure that they are not blocked by dirt, debris, or snow.
Carbon monoxide is a potentially deadly poison that can be generated by numerous household appliances. Strategic placement of CO detectors throughout the home or place of business is a must in order to alert occupants of any present high levels of the gas.