What Does Carbon Monoxide Smell Like?

Carbon monoxide is an odorless, tasteless gas that occurs when fuels aren’t completely burned off. Hundreds of people die from CO poisoning every year, and almost 50,000 more become ill.

Many things in the home produce CO, including your gas and oil-burning stoves and furnaces, vehicles and charcoal grills. Home appliances are built to vent these gases outside, but they could malfunction, causing a carbon monoxide leak or CO gas to build up to dangerous levels.

How is carbon monoxide detected?

Because you can’t smell or sense a carbon monoxide leak, installing working carbon monoxide detectors throughout your home is crucial. An alarm detects CO gas before it becomes hazardous, so you have enough time to leave and call 911.

There are three main types of carbon monoxide alarms: biomimetic alarms, metal oxide semiconductors and electrochemical sensors.

• Biomimetic sensors: Use a gel that changes color it absorbs too much CO into the alarm. The alarm activates once the gel changes color.
• Metal oxide semiconductor sensors: These sensors' circuitry detects high levels of CO gas.
• Electrochemical sensors: Electrodes in a chemical solution detect changes in the electrical current, which signify high levels of carbon monoxide. The alarm goes off once the current changes. These detectors are the most common in the United States and typically last from 5 to 10 years.

Does carbon monoxide smell like rotten eggs?

One reason carbon monoxide is so deadly is that it doesn’t have a natural odor.

The sulfurous, rotten-egg scent you sometimes smell in a pilot light or other natural gas is mercaptan. It’s added to natural gas, so it’s easier to know if there’s a leak.

Where should you put your carbon monoxide alarm?

Through state statutes, twenty-seven states and D.C. require carbon monoxide detectors in the home. Another 11 states require them in homes through the International Residential Code or an alteration to their state’s building regulations.

Carbon monoxide detectors should comply with state laws and operate under the most current UL standards.

•  Every floor in your home should have at least one carbon monoxide alarm.
• CO is lighter than air, so you should place the alarm on the wall, about five feet from the floor.
• You can also place a carbon monoxide alarm on the ceiling.
• Never put an alarm near a fireplace or the stove in the kitchen.
• If you’re only installing one CO alarm, ‌put it in the bedroom.

Read more about carbon monoxide placement: The Best Carbon Monoxide Detector Placement for Your Home

What are some signs of carbon monoxide poisoning?

Carbon monoxide gas poisoning is determined by many factors that include how much CO is in your home and the length of exposure.

Other factors include respiratory or heart issues, anemia, or if you are elderly or very young. 

What are some symptoms of gas leak poisoning?

Gas leak symptoms affect people differently depending on your health, so it’s possible a healthy adults might not experience symptoms even at 50 pp.

If your carbon monoxide detector goes off, ‌take it seriously, even if you don’t have any symptoms, and immediately seek help.

Initial symptoms:

• A mild headache
• Breathless
• Nausea
• Dizziness
• Exhaustion or weakness
• Even more intense headaches

Continued exposure:

• Upset stomach or vomiting
• Chest pains or tightness
• Sudden sleepiness
• Confusion
• Irritability
• Impaired judgment

Sustained, high levels of carbon monoxide:

• Lack of coordination
• Rapid loss of conscience
• Higher levels of confusion and disorientation
• Brain damage
• Death

What should you do if your carbon monoxide alarm goes off?

Since you can’t smell or even detect a CO gas leak, ‌it’s vital to have working carbon monoxide detectors installed in your home.

You should also ensure that your appliances function correctly to help prevent exposure to CO from broken equipment.

• If your carbon monoxide alarm goes off, ‌leave your home immediately.
• Open windows to vent your home on the way out.
• Once outside, call emergency services.
• If you or someone in your family is experiencing gas leak symptoms[1] , go to an emergency room or call 911.

Can you open a window to stop carbon monoxide poisoning?

As you're exiting your home, ‌try to vent windows on the way out for emergency personnel. Opening windows may help slow the spread of the gas, but it won’t completely vent carbon monoxide, especially if there are high levels of it in your home.

You should never open windows and stay inside after a carbon monoxide alarm goes off. Since it is a colorless, odorless gas, you won’t be able to tell how much CO gas is in your home. Instead, ‌vacate the property as soon as possible. 

10 things that give off carbon monoxide

CO is created whenever you burn fuel like wood, oil, propane, natural gas or charcoal. It’s also produced from brush fires, cigarettes and vaping.

Properly maintained appliances ‌create trace amounts of CO. When pipes and exhaust vents are working, they will ventilate that CO outside the home. Sometimes appliances or pipes break. Monitor these items around your home and immediately fix or replace them if damaged or broken.

Here are some things that give off carbon monoxide in your home:

1. Boilers

2. Water heaters

3. Gas stoves and ovens 

4. Clothes dryers

5. Vehicles

6. Furnaces or chimneys 

7. Camping stoves and camping fires

8. Generators or other gas-powered appliances like lawn equipment, power tools (i.e., high-pressure washers, floor buffers, compressors, welders), and grills

9.  Fireplaces

10. Gas-powered boats

ADT can help protect your home and family from carbon monoxide.

A carbon monoxide detector can be the first line of defense for sensing this odorless gas.

The ADT monitoring center calls you and sends help if it can’t get a hold of you. So, you can rest assured that your home is better protected 24/7.

Get reliable carbon monoxide detection and rapid response with ADT professional monitoring.