Carbon Monoxide Vs Carbon Dioxide 

Carbon dioxide (CO2) and carbon monoxide (CO). They kind of sound similar, don’t they? They both have the word carbon in them, and they both have the same abbreviation, except one of them has a “2” at the end. They are both gases, so sometimes they can be mixed up with each other, but these two are completely different from each other. It’s important to know the importance of the two, as it could potentially save your life.

About Carbon Dioxide (CO2)

Carbon dioxide is a colorless and odorless gas. It consists of one carbon compound and two oxygen compounds. The word “dioxide” comes from the Greek prefix “di”, which means “two”. That’s why there is a “2” after the "O" in its molecular formula: CO2. Carbon dioxide is a natural gas. We create it everytime we breathe. It plays an important role in the carbon cycle, making photosynthesis possible. Without it, life would be unsustainable.


So overall, carbon dioxide is good for us. It keeps every living thing alive, including us, and even has a large variety of unique applications. It’s seen many times in the world of entertainment, and even has its place in the medical field. So with that in mind, how does carbon monoxide compare?

About Carbon Monoxide (CO)

Carbon monoxide is a colorless and odorless gas, just like carbon dioxide. The word monoxide comes from the Greek prefix “mono,” meaning “one”. It consists of only one oxygen atom and one carbon atom, hence its molecular formula: CO. It results from badly ventilated fuel-burning appliances. Cars, gas ovens, and gas water heaters are examples of things that dispel CO. It is very flammable, so lighting a match near it can lead to fatal consequences.

Carbon monoxide doesn’t have any natural uses, only industrial applications. It mostly serves as a means of manufacturing metals. It react to specific metals like iron, cobalt, and nickel to form carbonyl compounds, which plays a role in manufacturing plastic. It also is used in industrial heating and fuel mixtures. This means car fuel contains carbon monoxide. While carbon monoxide is colorless and odorless, it will blend in with other burned gases, which is why when people see and smell the sickening black clouds of smoke dispelled by cars, many immediately think of this gas. Many appliances and products you can find in a supermarket are capable of producing carbon monoxide, like generators and charcoal grills. It’s required for manufacturing companies to warn people to make sure that their product must remain outside while under operation, and for good reason too.

It’s commonly known as “the Silent Killer” due to it being a deadly gas that you technically can’t see or smell. It can have a major negative impact on your lungs, blood, and nervous system. It displaces oxygen from your blood causing air hunger, a feeling where you can’t take in enough air. What’s even worse is that it could kill you faster than most other gases can.

Carbon Monoxide Poisoning

Like carbon dioxide, you want to avoid taking in too much carbon monoxide. When too much of this gas is present indoors, carbon monoxide poisoning occurs. This is much worse than what excessive carbon dioxide is capable of. While the human side effects of excessive carbon dioxide can be alleviated, carbon monoxide poisoning can easily lead to chronic complications, with heavy emphasis on the word chronic. Brain damage and heart failure is an especially common side effect, and because these side effects will end up chronic, the damage can stay permanent and get worse overtime, even when you’ve cleared yourself from excessive amounts of CO.

Tissue hypoxia is even common. As the gas starts displacing oxygen, it starts attacking your hemoglobin. This becomes a problem for the body carrying oxygen in the blood. It damages your lungs. This prevents them from won’t be able to consistently release oxygen, which can color your fingertips slightly blue and hurt your breathing rhythm.

Safe Pressure Levels

There’s a drastic difference in safe pressure levels when comparing carbon dioxide and carbon monoxide. You can survive a decent amount of CO2. Pressures up to 350-1,000 ppm (parts per million) is perfectly fine indoors. Going beyond that range could result in some questionable side effects. The least threatening one would be a slight case of drowsiness.


High CO2 pressure isn’t ideal, but a moderate amount is safe. It’s a natural gas that keeps us alive. Carbon monoxide, on the other hand, is toxic. It’s not safe to breathe it in. the recommended pressure levels are extraordinarily low. According to ASHRAE and OSHA standards, 9-35 ppm would be okay for long term exposure in a work environment, or about 8 hours. For short term usage, less than 3 hours, 800 ppm is acceptable. It really is not okay to go anywhere above those levels, but if you are in areas with pressures above 2,000 ppm, you’ll most likely start experiencing some common side effects before that monoxide poisoning really starts kicking in. This is why the utilization of products that produce this gas are done outside. Never, under any circumstances, should they be done indoors or in small spaces.

So as you can tell, the differences are like night and day. Although it is almost inescapable in this day and age, you want to avoid carbon monoxide as much as you can, as too much of it can easily kill you. If you feel like you’re in an area with carbon monoxide, we recommend stepping outside for some fresh air. It will save your life and feel refreshing at the same time. In some cases, calling poison control may be necessary too.

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