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Office of Research Services

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Carbon Monoxide: The Silent Killer

​Carbon monoxide (CO) is an odorless, colorless gas which is produced when fossil fuels such as gasoline, wood, coal, propane, fuel oil or methane burn incompletely. Exposure to CO can induce flu-like symptoms, difficulty breathing and even death depending on several factors such as the victim’s age, health status, the concentration of the CO inhaled and length of exposure. As a person is exposed to CO, oxygen is replaced in the blood and a condition known as carboxyhemoglobin saturation results. As the percentage of carboxyhemoglobin in the blood increases so, too, does the likelihood of severe carbon monoxide poisoning.


To ensure you and your family are protected from potentially life threatening levels of CO in the home, the following guidelines should be observed:

  • Follow manufacturer’s instructions regarding the proper maintenance, use and ventilation of heating and cooking equipment. Such equipment typically requires "breathing room" in order to operate safely and efficiently. Periodically check the perimeter of furnaces, water heaters and wood stoves to ensure that air intakes and pilot lights are not obstructed. Chimneys and flues should be cleaned and inspected for cracks and voids each year.

  • Always remove vehicles from garages and carports immediately after starting.  Similarly, shut off vehicles immediately after parking in enclosed areas. As part of routine maintenance, vehicles should be inspected for exhaust system leaks.

  • Always use barbeque grills (charcoal and propane) outside, in well ventilated areas.

  • When purchasing new heating and cooking equipment, ensure that the appliance has been tested and approved by an independent testing laboratory, such as Underwriters Laboratories (UL), for use in the intended manner and location.

  • Purchase and install home carbon monoxide detectors. Test these detectors at least once a month in accordance with manufacturer’s instructions. Ensure that all family members are familiar with the sound of the detector alarm so it will not be confused with an activated household smoke detector. Develop a home evacuation plan and practice "Exit Drills in the Home" (E.D.I.T.H.) periodically to ensure prompt evacuation in the event of an actual CO emergency.


If you have questions, or would like additional information, please contact the Division of the Fire Marshal, Office of Research Services, at 301-496-0487.