What is carbon monoxide poisoning?

Carbon monoxide (CO) poisoning happens when you breathe in fumes that contain CO. You can get very sick or even die if you breathe high levels of CO for even a few minutes.

What is carbon monoxide?

Carbon monoxide (CO) is a gas produced when gasoline and other fuels burn. It is invisible and colorless. You can’t smell or taste it. CO can build up quickly and is dangerous in high levels.

Where does carbon monoxide come from?

Carbon monoxide is in fumes (smoke) from:

  • Car and truck engines.
  • Small gasoline engines.
  • Fuel-burning space heaters (not electric).
  • Gas stoves.
  • Lanterns.
  • Heating systems, including home furnaces.
  • Burning charcoal, kerosene, propane or wood.

What happens to the body in carbon monoxide poisoning?

Red blood cells carry oxygen throughout your body. Your organs need oxygen to live. But red blood cells take in carbon monoxide faster than oxygen. At high levels, CO crowds out oxygen in your bloodstream.

If you breathe too much CO, organs such as your brain and heart don’t get enough oxygen. CO can also combine with proteins in the body and damage your cells and organs. If you inhale a lot of CO, you can lose consciousness (pass out) and suffocate within minutes.

How common is carbon monoxide poisoning?

Each year in the United States, accidental CO poisoning:

  • Kills more than 400 people.
  • Sends an additional 20,000 people to emergency rooms.
  • Hospitalizes more than 4,000 people.

Who is most at risk for CO poisoning?

Everyone is at risk for carbon monoxide poisoning. In winter, risks are higher because of improperly maintained heating systems or people warming up cars in garages. At highest risk are:

  • Unborn babies.
  • Infants.
  • Older adults. Most deaths from CO poisoning happen to adults 65 and older.
  • People living at high altitudes.
  • People with chronic heart disease, anemia or respiratory (breathing) problems.
  • People with already-high CO levels, such as those who smoke.

People who have CO exposure through their jobs are also at higher risk. Harmful CO levels exist in places such as boiler rooms, warehouses or petroleum refineries. Occupations with high CO levels include:

  • Firefighters.
  • Forklift operators.
  • Garage mechanics.
  • Police officers.
  • Taxi drivers.
  • Tollbooth attendants.
  • Welders.

What causes carbon monoxide poisoning?

Many appliances and vehicles burn fuel and emit (release) carbon monoxide. When people use and maintain these appliances correctly, the CO levels usually aren’t harmful.

CO poisoning happens when people use fuel-burning appliances without proper ventilation or in other unsafe ways. For example, it can be dangerous if you:

  • Let your car or truck idle in an enclosed space, such as a garage.
  • Have a vehicle with a blocked exhaust system, such as by snow in the tailpipe.
  • Use a kerosene heater or gas barbecue grill indoors.

What are symptoms of carbon monoxide poisoning?

The symptoms of low levels of CO exposure are similar to flu symptoms or food poisoning:

Moderate CO exposure can cause symptoms such as:

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