Carbon Monoxide Detectors

Carbon monoxide, though often generated simultaneously with carbon dioxide, is far more poisonous. Carbon dioxide displaces oxygen and prevents breathing, while carbon monoxide limits the blood's ability to carry oxygen.3

Carbon monoxide detectors, also known as carbon monoxide alarms, are devices that monitor the level of carbon monoxide in a home, sounding an alarm if the levels become dangerously high. Carbon monoxide detectors can be triggered by accumulating lower, continuous levels of CO or by sudden, high concentrations. Though a CO detector is likely to work in the case of a sudden, high level of CO, proper installation, maintenance, and drafting of all combustion appliances is essential to maintaining non-harmful levels.

General Recommendations
Carbon monoxide detectors are recommended for all dwelling units. They should be installed within 10 feet of any bedroom or other room used for sleeping. Minnesota law now requires CO detectors for all new residential construction and all existing single family houses. In August 2009, all residential dwellings will be required to have carbon monoxide detectors.4

Environmental Context
Carbon monoxide poisoning represents a significant danger to health. Each year, around 500 people die and thousands are hospitalized from exposure to carbon monoxide.6

Notes on Use
Carbon monoxide detectors are easy to install. Many plug into a wall socket and others operate on a battery. If the plug-in model is chosen, make sure that it has a battery backup and is not plugged into an outlet operated by a switch. There are several different types of CO detectors, though there is little difference in the effectiveness between the sensor mechanisms. Follow the manufacturer's recommendations for the location of CO fixtures in or within 10 feet of any sleeping room.

Be aware of the signs of existing carbon monoxide concentrations, including:7

  • Black soot from a combustion device (furnace, water heater, dryer) on appliances or vents
  • Excessive moisture on inside of walls and windows
  • Poor drafting of a fireplace or stove
  • Popping or banging noises from an oil furnace or heater
  • Any of the above mentioned symptoms for carbon monoxide exposure (dizziness, headaches, nausea, etc.)
  • Poorly functioning furnace that may run continually
  • Decreased hot water heater function or hot water supply
  • Burning odor
  • Loose or cracked chimney or vent
  • Debris or soot accumulating in chimney or combustion appliances

Though the installation of carbon monoxide detectors is an important safety measure, there are other measures that can lower the possibility of carbon monoxide exposure:8

  • Have combustion equipment and vents regularly checked and serviced
  • Never run a car inside a garage, even with the garage door open
  • Install forced- or induced-draft vents on all combustion appliances
  • Never operate un-vented combustion appliances in sleeping quarters
  • Never burn charcoal in enclosed or semi-enclosed spaces, such as tents, homes, or garages
  • Never operate flameless chemical (catalytic) heaters in enclosed space, as these produce CO
  • Do not operate gas ovens, ranges, or dryers for heating a home
  • Never operate a generator in an enclosed space or close to open windows
  • Make sure that your chimney or vent is free from blockage

Other Resources


Web Sites

1 "Carbon Monoxide Basic Information." US EPA Web site: Indoor Air Quality. 27 May 2008. U.S. Environmental Protection Agency. 28 Jul 2008.
2 EPA IAQ page on CO, accessed 08.05.08.
3 United States. Department of Labor. Occupational Safety and Health Administration. OSHA Fact Sheet: Carbon Monoxide Poisoning. 2002. 11 Aug 2008.
4 ibid.
5 State of Minnesota. MInnesota State Fire Code 299.F51.
6 "Carbon Monoxide: The "Invisible" Killer." U.S. Consumer Products Safety Commission. Washington, DC. 28 Jul 2008.
7 "Carbon Monoxide Dangers." Minnesota Department of Commerce Web site. 2000. Minnesota Department of Commerce. 28 Jul 2008. AND State of Minnesota. Office of Reivsor of Statues. Minnesota Rules, Chapter 7672.0600 and Chapter 7675.0600: Minimum Envelope Criteria. 28 Jul 2008. AND
8 "Carbon Monoxide Dangers." Minnesota Department of Commerce Web site. 2000. Minnesota Department of Commerce. 28 Jul 2008.