Carbon Monoxide Safety


Carbon Monoxide Safety

What is carbon monoxide?

Carbon monoxide, also known as CO, is called the “Invisible Killer” because it's a colorless, odorless, poisonous gas. More than 150 people in the Unites States die every year from accidental nonfire-related CO poisoning associated with consumer products, including generators. Other products include faulty, improperly used or incorrectly vented fuel-burning appliances such as furnaces, stoves, water heaters and fireplaces. Source: Consumer Product Safety Commission

Know the symptoms of CO poisoning

Source: Consumer Product Safety Commission

Because CO is odorless, colorless, and otherwise undetectable to the human senses, people may not know that they are being exposed. The initial symptoms of low to moderate CO poisoning are similar to the flu (but without the fever). They include:

  • Headache
  • Fatigue
  • Shortness of breath
  • Nausea
  • Dizziness

High level CO poisoning results in progressively more severe symptoms, including:

  • Mental confusion
  • Vomiting
  • Loss of muscular coordination
  • Loss of consciousness
  • Ultimately death

Symptoms of CO poisoning

CO enters the body through breathing. CO poisoning can be confused with flu symptoms, food poisoning and other illnesses. Some symptoms include shortness of breath, nausea, dizziness, light headedness or headaches. High levels of CO can be fatal, causing death within minutes.

The concentration of CO, measured in parts per million (ppm) is a determining factor in the symptoms for an average, healthy adult.

  • 50 ppm: No adverse effects with 8 hours of exposure.
  • 200 ppm: Mild headache after 2-3 hours of exposure.
  • 400 ppm: Headache and nausea after 1-2 hours of exposure.
  • 800 ppm: Headache, nausea, and dizziness after 45 minutes; collapse and unconsciousness after 1 hour of exposure.
  • 1,000 ppm: Loss of consciousness after 1 hour of exposure.
  • 1,600 ppm: Headache, nausea, and dizziness after 20 minutes of exposure.
  • 3,200 ppm: Headache, nausea, and dizziness after 5-10 minutes; collapse and unconsciousness after 30 minutes of exposure.
  • 6,400 ppm: Headache and dizziness after 1-2 minutes; unconsciousness and danger of death after 10-15 minutes of exposure.
  • 12,800 ppm: Immediate physiological effects, unconsciousness and danger of death after 1-3 minutes of exposure.

How can I prevent CO poisoning?

  • Make sure appliances are installed and operated according to the manufacturer's instructions and local building codes. Most appliances should be installed by qualified professionals. Have the heating system professionally inspected and serviced annually to ensure proper operation. The inspector should also check chimneys and flues for blockages, corrosion, partial and complete disconnections, and loose connections.
  • Never service fuel-burning appliances without proper knowledge, skill and tools. Always refer to the owner's manual when performing minor adjustments or servicing fuel-burning equipment.
  • Never operate a portable generator or any other gasoline engine-powered tool 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.
  • Install a CO alarm that meets the requirements of the current UL 2034 safety standard. A CO alarm can provide some added protection, but it is no substitute for proper use and upkeep of appliances that can produce CO. Install battery-operated CO alarms or CO alarms with battery backup on every level of the home and outside sleeping areas. Interconnected CO alarms are best; when one sounds, they all sound. Make sure the alarm cannot be covered up by furniture or draperies.
  • 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 garage door open.
  • Never use gas appliances such as ranges, ovens, or clothes dryers to heat your home.
  • Never operate unvented fuel-burning appliances in any room where people are sleeping.
  • Do not cover the bottom of natural gas or propane ovens with aluminum foil. Doing so blocks the combustion air flow through the appliance and can produce CO.
  • During home renovations, ensure that appliance vents and chimneys are not blocked by tarps or debris. Make sure appliances are in proper working order when renovations are complete.

Digital media library

Here you’ll find social media content, pictographs, stock photos, videos and b-roll to increase awareness about carbon monoxide poisoning.  Winter Fire Safety

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install carbon monoxide alarms

Outreach materials from the U.S. Fire Administration