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Carbon Monoxide (CO): What It Is And How It Works

Unawareness of carbon monoxide (CO) can lead to hazardous or even fatal situations. Check out this article right now to educate yourself on this gas!

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Every year, thousands of people die from exposure to carbon monoxide (CO), and millions have to visit hospitals because of CO poisoning. 

Unfortunately, awareness about this dangerous gas hasn’t been widely spread in our society. To make matters worse, the gas is not easy to identify with human senses. 

The best solution for this problem is to fill yourself in with CO knowledge. This article will help you with that task!

What Is Carbon Monoxide (CO)?

Carbon monoxide (CO) is a toxic gas with no odor or taste. It forms when carbon in combustion burns incompletely. CO catches fire easily and creates a violet flame when it burns.

What Is Carbon Monoxide
Carbon monoxide

This substance weighs less than air and can be produced through manufacturing processes or natural chemical reactions in volcanoes and forest fires.

Where Can Carbon Monoxide Be Found?

CO is the result of the lack of oxygen needed for carbon dioxide to be produced. This happens in the case of a fire or a combustion engine operating in an enclosed space.

Where Can Carbon Monoxide Be Found?

Human activities that involve fuel-burning appliances like wood stoves, generators, gas water heaters release carbon monoxide. 

This substance comes from parking areas, roads, or attached garages where there are cars, buses, truck exhausts. Poorly-maintained boilers or furnaces can also be potential sources.

Although mainly a manufactured pollutant, CO does occur naturally. It exists when a volcano erupts, in coal mines, or even from flashes of lightning.

CO’s Effects On The Environment

Carbon monoxide harms many aspects of our planet:  air, climate, plants, and animals.

Due to its nature, this substance can diffuse evenly in the atmosphere if released. Then it dissolves in the moisture thanks to its solubility. Once there is enough moisture, acid rain forms and reaches the land. The acid robs the essential nutrients from the soil and leeches aluminum from clay particles. 

CO’s contamination of living beings in the environment results from air pollution and acid rain. The soil after rain is not rich enough for plants to thrive. Trees in these areas often have damaged roots, weakness, stunted growth, and eventually die.

CO’s Effects On The Environment

The high concentration of carbon monoxide takes aluminum away from land and brings them to the river, contaminating the water. In an interconnected ecosystem where animals inhabit and drink from seas, ponds, streams, that fact threatens their lives. 

Some of the common symptoms of CO poisoning on animals are coughing, seizures, unconsciousness, dizziness.

Health Effects Of CO

Risks Of Exposure To CO

As mentioned above, this substance is highly flammable. An area with a great amount of it contains risks of catching fire.

The gas is odorless, tasteless, and colorless, making it go undetected to the naked eye. When accumulating to a certain amount, it steals people’s lives away when they let their guard down: in their sleep or when they’re drunk. Thus, CO is often called “a silent killer”.

CO’s effects on human health range from mild to serious. Regular exposure to low levels of carbon monoxide in the home or workplace can cause headaches, nausea, dizziness, and poor concentration. 

People often mistake poisoning with a small amount of CO for signs of flu. However, unlike the flu, those in the latter can quickly recover when they move into the fresh air.

Regular exposure to low levels of carbon monoxide in the home or workplace can
Headache is one common symptom

Prolonged exposure to CO can cause more severe reactions such as vomiting, unconsciousness, brain damage, abortion, breathing difficulties, or muscle weakness. 

When the level of CO concentration goes beyond 150 ppm (parts per minute – a unit to measure poisoning), humans will experience confusion and eventually die.

How Does CO Harm Human Health?

This poisonous gas harms our body by preventing cells from getting oxygen.

In hemoglobin, an iron compound called heme brings oxygen from the lungs or gills to the rest of the body. With the appearance of CO, that delivery process is interrupted. The gas particle can easily bond with heme. Compared to oxygen, CO’s affinity to bind with heme is two hundred times greater. 

When the substance attaches to heme, it produces carboxyhemoglobin and makes blood’s ability to carry oxygen deteriorate. It also hinders the release of oxygen from heme to other parts of the body.

CO not only disrupts the delivery of oxygen in the blood but also reduces the oxygen storage in muscles by forcing oxygen out of myoglobin. 

All body organs are vulnerable to the substance’s attack, especially our brains and hearts, which use the most oxygen. People with respiratory or cardiovascular diseases might not be able to fight off CO’s negative effects.

Carbon Monoxide At Home

Carbon Monoxide Levels In Homes

The safe level of CO indoors should be the same as that outdoors. According to the U.S National Ambient Air Quality Standards, outside air should contain nine ppm in 8 hours. 

Normally, CO builds up more in urban areas than in rural areas. If CO concentration in your house is higher than the natural level, look out for harmful sources of carbon monoxide indoors.

What Causes Carbon Monoxide In The Home?

Kitchen Area 

Gas stoves and cooking areas can be significant sources of carbon monoxide in the home, especially when there is no proper ventilation system. Always maintain the kitchen areas and stoves in a clean and working state to avoid this.

Heating Appliances

Furnaces, space or water heaters, dryers run on fuel in some households. When these appliances are in constant use during cold months, carbon monoxide can accumulate inside rooms. Frequent inspection and maintenance would protect your family from that dangerous possibility.


Grills heated by propane or charcoal are direct CO sources if used in enclosed spaces. Suitable places to grill food should have more open air.


Fireplaces are many people’s go-to choice to provide heat during winter days. The oxygen needed to burn down the wood completely will not be available if the ventilation is not good. Incomplete oxidation of that material can emit CO into your house.

Therefore, a fireplace must always be installed with chimney pipes.

F ireplace

Portable Generator

Using gas-fueled portable heat generators releases a great deal of CO. Therefore, a house with limited space is not an ideal place for those appliances. Users should use them in the backyard about 25 feet away, downwind from open doors.


Except for electric ones, most traditional vehicles need fuel combustion to function. Some people have the habit of starting their car in the garage, which allows this toxic substance to build up. 

Thus, remember to keep the garage door open when you do it. An annual inspection of the vehicles is also recommended as it uncovers the CO-leaking spots that you might not know.

Tobacco Smoke

Smoking contributes to carbon monoxide indoor air pollution since the burned tobacco releases that gas. The people in the same room can accidentally inhale the smoke, damaging their lungs. 

Tobacco Smoke
obacco Smoke

How To Prevent CO Poisoning At Home?

Proper Usage Of Fuel-Burning Appliances

You need to list all the fuel-burning devices in the house and maintain them properly. Make sure that there is good ventilation or flue for those appliances. 

The risks come from not only the ventilation system but also the machines themselves. Therefore, hiring a skillful contractor to check them is advisable.

Aware Of CO Poisoning’s Symptoms

Knowing what CO poisoning is like can effectively protect you and other people from this dangerous gas. That way, you can detect early signs of exposure and save them in time. 

You should also learn how to differentiate between flu and carbon monoxide poisoning. For example, if you don’t have fevers, body aches, or swollen lymph nodes, the disease is caused by CO.

Get A CO Alarm

Since humans can not identify CO in the air, a CO alarm would be of great help. When the gas level in the air increases, the alarm goes off to alert you about the danger.


Who Is Prone To CO Poisoning?

While everyone is vulnerable to CO’s poison, some people have greater risks. They include:

  • Elderly and young children
  • People with respiratory diseases or sickle cell anemia 
  • Those with Cardiovascular conditions

Where To Install CO Alarms?

This device should be placed in the hallway outside the bedroom and on every story of the house.

Is CO A Problem In The Summer?

Yes. The increased number of CO-related cases in winter does not mean the gas is not dangerous in summer. Vehicles like cars, buses, trucks, and fuel-burned kitchen devices work throughout summers and pose risks whenever they emit exhaust or smoke.

What Is The First Aid For CO Poisoning?

When there are people having CO poisoning, the first thing to do is to move them out of the gas-leaking area. Then, you should seek medical treatment right after.


Carbon monoxide (CO) is a poisonous substance that affects both humans and the environment. It contaminates our air, water and deprives creatures of their lives. 

Under exposure to CO, the human body produces serious reactions, including death. Awareness of this gas needs to be raised so people can stay away from the threats and prevent CO from destroying our planet. 


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