12 Signs There Is Carbon Monoxide in Your House

Medically Reviewed on 12/16/2022
Carbon monoxide (CO) is a poisonous, odorless, and colorless gas.
Carbon monoxide (CO) is a poisonous, odorless, and colorless gas.

Symptoms of carbon monoxide poisoning vary depending on the severity of exposure and the overall health of the person. Carbon monoxide (CO) is a poisonous, odorless, and colorless gas.

The potential sources of carbon monoxide in the house include:

  • Poorly functioning heating systems, water heaters, and fuel-burning devices with no vents (for example, kerosene heaters, charcoal grills, camping stoves, and gasoline-powered electrical generators)
  • Motor vehicles

Other carbon monoxide poisoning causes

  • Open-air exposure to motorboat exhaust can also cause carbon monoxide poisoning.
  • The underground electrical cable fires produce large amounts of carbon monoxide gas that may seep into nearby houses.
  • Carbon monoxide poisoning may happen due to smoking hookah.

The following 12 signs may help you to detect a carbon monoxide leakage or buildup in your home, such as:

  1. You see black, sooty marks on the front covers of gas fires.
  2. There is heavy condensation built up at the windowpane where the appliance is installed.
  3. Sooty or yellow/brown stains on or around boilers, stoves, or fires.
  4. Smoke building up in rooms.
  5. Yellow flames coming out from gas appliances except at natural gas fireplaces.
  6. The pilot lights blow out frequently.
  7. Solid fuel fires burn a lot slower than usual.
  8. People in your home have these symptoms:
  9. Symptoms disappear once you are away from your home.
  10. You get seasonal symptoms, such as headaches during the winter when central heating is used more frequently.
  11. Pets become ill.
  12. Symptoms appear or seem to get worse when using fuel-burning equipment.

What is carbon monoxide poisoning?

Carbon monoxide poisoning is a potentially fatal illness that occurs when carbon monoxide gas builds up in the blood. 

When carbon monoxide is inhaled, it replaces oxygen attached to the pigment hemoglobin in the blood. This hampers the delivery of oxygen to various tissues in the body, which can lead to serious damage and even death. Carbon monoxide poisoning is a leading cause of death in the United States, killing thousands each year and mostly affecting people in their sleep.

Carbon monoxide is a colorless, odorless, and tasteless gas that is formed from burning fuel, such as gasoline, coal, propane, and wood, and it usually builds up in ill-ventilated places. Sources of carbon monoxide may include

  • automobile engines,
  • charcoal grills,
  • indoor heating systems,
  • tobacco smoke,
  • leaky furnaces,
  • water heaters that use natural gas, and
  • gas stoves.

What are symptoms of carbon monoxide poisoning?

Symptoms of carbon monoxide poisoning vary depending on the severity of exposure and the overall health of the person.

In general, carbon monoxide poisoning symptoms may include:

Can you survive carbon monoxide poisoning?

Carbon monoxide poisoning can be treated if you seek immediate medical attention. 

If you suspect that someone has been poisoned with carbon monoxide, move them to fresh air while ensuring your own safety. Go to the emergency room or call the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States.


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How to prevent carbon monoxide leaks in your house

It is essential to detect any carbon monoxide leak in your house to prevent any hazards. Carbon monoxide is a silent killer, killing approximately 400 Americans every year. Hence, it is imperative to check and prevent any leaks to avoid any mishaps.

Some tips to prevent carbon monoxide leaks in your home include:

  1. Fit a battery-operated or battery backup CO detector alarm near your bedroom to detect any CO leak.
  2. Service your heating system, water heater, and any other gas, oil, or coal-burning appliances every year by a qualified technician.
  3. Do not use portable flameless chemical heaters indoors.
  4. If there is a leak from the refrigerator, seek the help of an expert technician. The leak may be due to carbon monoxide.
  5. Buy gas equipment, which carries the seal of a national testing agency.
  6. Make sure your gas appliances are inspected for proper ventilation.
  7. Check or clean your chimney every year. Chimneys can be blocked by debris, which can cause CO buildup inside your home or cabin.
  8. Never use tape, gum, or something else to seal the vent pipe. This kind of temporary seal can make CO build up in your home, cabin, or camper.
  9. Never use a gas range, cloth dryer, or oven for heating the room because it may lead to the buildup of carbon monoxide.
  10. Never burn charcoal indoors. Burning charcoal gives off CO.
  11. Never use a portable gas camp stove indoors. Using a gas camp stove indoors can cause CO to build up inside your home, cabin, or camper.
  12. Never use gasoline-powered engines inside your home, basement, or garage or less than 20 feet from any window, door, or vent.
  13. Avoid smoking inside your home.

How long does it take to get carbon monoxide poisoning?

How long it takes to get carbon monoxide poisoning depends largely on the concentration of carbon monoxide in the air, as well as your age, gender, and general health.

According to the Environmental Protection Agency (EPA), the national ambient air quality standard (NAAQS) for carbon monoxide is 9 ppm (parts per million) for over 8 hours, and this threshold must not be exceeded more than once a year. 

  • If the carbon monoxide concentration in the air is much higher, signs of poisoning may occur within 1-2 hours
  • A very high carbon monoxide concentration can even kill an exposed individual within 5 minutes.

For healthy workers, the U.S. Occupational Health and Safety limit is 50 ppm. Even lower levels of exposure, however, can cause long-term adverse effects on the heart, brain, and nerves if the exposure is prolonged. Children, people who smoke, and those with heart and lung conditions are at an increased risk of carbon monoxide poisoning.

Health Solutions From Our Sponsors

Medically Reviewed on 12/16/2022
NHS. Carbon Monoxide Poisoning. https://www.nhs.uk/conditions/carbon-monoxide-poisoning/

Greiner T. Carbon Monoxide Poisoning: Health Effects (AEN-166). ISU Extension Publication. https://www.abe.iastate.edu/extension-and-outreach/carbon-monoxide-poisoning-health-effects-aen-166/

Drugs.com. Carbon Monoxide Poisoning. https://www.drugs.com/health-guide/carbon-monoxide-poisoning.html

U.S. Environmental Protection Agency. Carbon Monoxide's Impact on Indoor Air Quality. https://www.epa.gov/indoor-air-quality-iaq/carbon-monoxides-impact-indoor-air-quality