Does Carbon Monoxide Have a Smell? What You Need to Know

Carbon monoxide (CO) is often called the “silent killer” for a good reason—it’s colorless, tasteless, and completely odorless. So, what does carbon monoxide smell like? Unfortunately, the answer is nothing. Unlike natural gas, which has a chemical additive to give it a strong, sulfur-like odor, carbon monoxide is a byproduct of incomplete combustion and has no odor-enhancing additives.

To help detect gas leaks, natural gas providers use a substance called mercaptan, which gives off a rotten egg smell as a safety measure. Because of this, people may mistakenly believe that they can detect carbon monoxide through scent. However, this is a dangerous misconception. You simply cannot rely on your sense of smell to detect a carbon monoxide leak—even at dangerous levels.

The presence of carbon monoxide can only be identified without the help of a reliable detection system. Despite the fact that these detectors are effective and simple to install, UL Research Institutes reports that 36% of U.S. adults do not have any type of carbon monoxide alarm in their home, leaving families vulnerable. Many of those surveyed incorrectly assumed that a smoke detector would be able to detect CO.

What Carbon Monoxide Smells Like—And Why That’s a Problem

When people ask, "What does carbon monoxide smell like?" or “Carbon monoxide smells like what?”, they’re often hoping for a warning sign. But since CO lacks any detectable odor, that absence is what makes it especially dangerous.

Some individuals may associate symptoms of carbon monoxide poisoning with nausea or headaches caused by household odors like burning dust or exhaust fumes. However, these smells are not indicators of CO itself but rather of other sources that may also produce carbon monoxide, such as malfunctioning appliances.

Because CO gas offers no sensory warnings, exposure can happen slowly or suddenly without any indication. This makes it particularly hazardous during sleep, or in enclosed spaces with limited ventilation.

The Real Dangers of an Odorless Gas

Each year, carbon monoxide poisoning sends over 100,000 people to the emergency room in the U.S. alone. The most dangerous part? Many victims never realize they’ve been exposed until symptoms become severe—or even life-threatening.

CO binds with hemoglobin in your blood more efficiently than oxygen, reducing the body’s ability to deliver oxygen to vital organs. Even low levels can lead to symptoms like:

• Headache

• Fatigue

• Shortness of breath

• Confusion

• Nausea

• Unconsciousness

In high concentrations, carbon monoxide poisoning can be fatal within minutes. The lack of odor removes one of the key warning signs we rely on in other emergencies—like fire or gas leaks.

How to Detect Carbon Monoxide in Your Home

Since you can't smell carbon monoxide, the most effective way to protect your family is by installing carbon monoxide detectors in your home. These devices monitor CO levels and sound an alarm when danger is detected.

To maximize coverage, place detectors:

• Near sleeping areas: Carbon monoxide exposure is especially dangerous at night, when you may not notice symptoms like dizziness or nausea. A properly placed detector ensures the alarm will wake you in time to act.

• On each level of your home: Carbon monoxide can accumulate on any floor, not just in basements or near appliances. Place at least one detector on every level, including finished attics and basements, to ensure full-home protection.

• Close to potential CO sources: Install detectors near fuel-burning appliances such as furnaces, water heaters, gas ranges, fireplaces, and inside or just outside attached garages. These areas pose the highest risk for CO buildup due to combustion. Just be sure to follow manufacturer guidelines for distance, as detectors should not be installed too close to appliances to avoid false alarms.

Test detectors regularly and replace batteries as recommended by the manufacturer to ensure continuous protection.

Smart Security and Monitoring for Peace of Mind

While standalone CO detectors are critical, they rely on someone hearing the alarm and taking action. What happens if no one is home or asleep?

Professionally monitored carbon monoxide detectors offer a crucial safety advantage. When integrated into a smart home security system, these detectors notify a 24/7 monitoring center if dangerous levels of CO are detected. Emergency services are dispatched even if you're not home or unable to respond.

Carbon monoxide detectors that are fully integrated with a smart security system, such as those installed by Brinks Home™, can help facilitate added safety during emergencies.

Protect Your Home From Carbon Monoxide Exposure

Brinks Home offers professional installation for all of its products to ensure complete and effective coverage, and our carbon monoxide detectors are integrated into a professionally monitored security system. Whether you're home or away, you can count on rapid response in the event of an emergency.

Carbon monoxide exposure may be odorless, invisible, and potentially fatal—but with the right technology, it’s also preventable. The most important step you can take is to stop relying on your senses and start depending on smart, monitored detection systems.

Don’t leave your family’s safety to chance. Contact us at Brinks Home today for a free quote on a home security system that includes a professionally monitored carbon monoxide detector.