Carbon Monoxide vs. Carbon Dioxide: What's the Difference

People often confuse carbon monoxide (CO) and carbon dioxide (CO2) because of their similarities. Not only do the two gases have similar names and chemical symbols, but they also have similar physical characteristics. Just like carbon monoxide, carbon dioxide is invisible and odorless, and it can also be deadly.

Hence, it’s important to have sensors for both inside your home. Since they are completely different chemicals, a sensor that detects carbon monoxide isn’t necessarily going to detect carbon dioxide. While trace amounts of CO and CO2 are common inside the home and won’t cause any harm, both gases can build up to dangerous levels if conditions are right.

What is carbon monoxide?

CO is a common gas found in trace amounts in our atmosphere. It is also a byproduct of the partial oxidation of methane during combustion. According to the CDC, each year, more than 400 Americans die from unintentional CO poisoning not linked to fires, more than 20,000 visit the emergency room, and over 4,000 are hospitalized.

A good rule of thumb is if something is burning, you’re likely creating carbon monoxide. That’s why it’s important to have at least one carbon monoxide sensor in your home.

How much carbon monoxide is dangerous?

You know carbon monoxide is dangerous and that too much carbon monoxide can kill you. But it’s also an invisible and odorless gas, so how do you know when it’s present, and how much carbon monoxide is lethal?

Carbon monoxide can become lethal, for example, if you have a gas leak at your kitchen stove or if the catalytic converter in your car isn’t functioning. Without a carbon monoxide sensor, you likely won’t know you have too much carbon monoxide in your home or garage until you have symptoms of CO poisoning. Thus, it’s critical to have carbon monoxide sensors in your home to protect you and your family from illness or even death.

Symptoms of CO poisoning

If you suddenly feel sick for no reason, like the sudden onset of a headache or feelings of dizziness, it’s important to leave your home immediately. You could be experiencing CO poisoning. Symptoms of carbon monoxide poisoning are similar to those of the flu:

• Headache

• Dizziness or weakness

• Upset stomach or vomiting

• Chest pain

• Confusion

But imagine if you’re sleeping in your bedroom or relaxing in front of your gas fireplace with a bottle of wine. You won’t necessarily know you’re having symptoms without a CO detector’s aid in both cases.

What you need to know about carbon monoxide levels

How much carbon monoxide is safe? Small amounts of carbon monoxide exposure, ranging from one to 70 parts per million (ppm), will not cause any adverse health effects.

However, if you are exposed to carbon monoxide levels in the atmosphere over 70 ppm, you’ll likely start developing symptoms of carbon monoxide poisoning. When carbon monoxide levels in the air exceed 150 ppm, you could lose consciousness or die.

How to prevent CO poisoning in your home

If you don’t already have a carbon monoxide detector in your home, consider installing one as soon as possible. They are inexpensive and easy to install.

If you have CO detectors already, make sure that you replace the batteries at least once every five years. Also make sure you have a detector within hearing of any area in your home where you or a loved one might sleep. You can purchase a sensor that will give you a digital readout of CO levels in your home or connect your sensors to a smart home hub.

It’s also a good idea to check any appliances in your house that use natural or propane gas, oil, or coal for proper functioning. This might include your HVAC system, water heaters, stoves, and gas fireplaces. If you suspect any of these appliances are malfunctioning or leaking, contact a professional to inspect them.

Here are some other tips to keep you and your family safe from CO poisoning:

1. If you’re running your house on a generator, make sure your CO detectors have a battery backup. Power outages can often cause a gas leak or buildup to occur.

2. If you burn charcoal, make sure to do so in a well-vented space and certainly not inside your home. Anytime you burn charcoal, like when grilling steaks outdoors on a charcoal grill, make sure there is a constant airflow.

3. If you perform your own repairs on any ventilation shaft in your home, make sure you use the proper materials and tools. Patching a ventilation pipe with duct tape is not adequate protection from a gas leak.

4. Don’t ever use chemical heaters indoors, even if they don’t have a flame.

5. Don’t use a gas camping stove indoors.

6. Never use a gas stove or oven to heat your house.

7. Check your chimney for debris that might be blocking airflow. If you use your wood-burning fireplace regularly, it’s a good idea to have a professional clean it once a year.

8. If you experience any odors coming from a gas appliance inside your home, like your stove or gas fireplace, call a professional to service it immediately.

9. Never use a gas-powered generator inside your home, and when using outdoors, make sure it’s at least 20 feet away from any open windows on your house.

What is carbon dioxide?

Carbon dioxide is also naturally occurring and common in our atmosphere. CO2 is the gas plants need to survive and is a byproduct of animal respiration, fermentation, combustion, and other chemical reactions. It is also the gas that most vehicles emit that have a catalytic converter. CO2 is also a common gas pressurized inside cans.

Since carbon dioxide is slightly denser than air (as opposed to carbon monoxide which is slightly lighter), if it leaks in large quantities either naturally or unnaturally, it can cause a cloud to linger at surface level. There are times when natural events can cause huge clouds of CO2 to emit into the atmosphere, which can be extremely dangerous.

Symptoms of CO2 poisoning

While CO2 leaks are infrequent, it’s still important to know the symptoms, which could include the following:

• Disorientation

• Increased heart rate

• Muscle tremors

• Shortness of breath

• Acidic taste in the mouth

If you think there is a chance you are experiencing carbon dioxide poisoning, make sure to leave the area immediately.

Which sensors do I need?

Carbon dioxide poisoning in the home is rare, but if you have CO2 sensors as well as carbon monoxide detectors in your home, your home security service provider will notify you when either is triggered. If you’re worried about CO poisoning, consider professional monitoring by a security company that connects your sensors to your security system.

Want to learn more about protecting your family from CO or CO2 poisoning? Brinks Home™ can assist you with tying your carbon monoxide sensors into your home security system. Contact a senior security consultant for more details.