Dangerous Carbon Dioxide: Why and How to Detect It?

While most of us are particularly afraid of the deadly poisonous carbon monoxide, carbon dioxide should definitely not be underestimated either. Its increased concentration can cause health problems and, in extreme cases, lead to death. How does carbon dioxide form, what concentration is harmful to human health, and how can its presence be detected?

What is Carbon Dioxide and How Does It Form?

Carbon dioxide (CO₂) is a gas that is colourless and odourless. It is heavier than air, and therefore tends to stay close to the ground. This gas, composed of one carbon atom and two oxygen atoms, is a common component of the Earth's atmosphere. Carbon dioxide is primarily produced during breathing and other biological processes.

It is also generated during combustion and is produced by microorganisms and photosynthesizing plants. Given that carbon dioxide is a product of many biological processes, including breathing, it is found all around us. Usually, this gas is not dangerous, but in enclosed spaces, it can reach health-damaging concentrations.

Concentration of Carbon Dioxide

While normal concentrations of carbon dioxide are harmless, higher concentrations of this gas can cause health issues. In the natural environment, the concentration of carbon dioxide is around 400 ppm, and in industrial areas, this value is somewhat higher.

It is stated that a concentration of CO₂ of 1,000 ppm negatively affects humans, making us feel tired. Exceeding 2,000 ppm leads to headaches and decreased concentration, and at concentrations above 5,000 ppm, most people experience an increased heart rate. A concentration exceeding 45,000 ppm can lead to unconsciousness and subsequent death due to lack of oxygen. In the Czech Republic, the limit for carbon dioxide in buildings is set at 1,500 ppm.

Adequate ventilation ensures a low concentration of CO₂ in the room.

What are the Symptoms of Carbon Dioxide Poisoning?

High concentrations of carbon dioxide accumulating in enclosed spaces negatively affect air quality. The so-called stale air in a room can cause fatigue, lead to headaches, and have a negative impact on sleep quality.

Carbon dioxide poisoning can also manifest as confusion, nausea, and lethargy. If you observe these symptoms in someone, take them to fresh air and ventilate the room well.

CO₂ Detectors

The only 100% reliable way to detect harmful concentrations of CO₂ is with carbon dioxide detectors, which are also known as sensors, alarms, or CO₂ sensors. It is not possible to detect this gas with the senses, as it is colourless, tasteless, and odourless.

Carbon dioxide detectors are useful not only in homes but should also be installed in public buildings, offices, greenhouses, underground garages, breweries, and wine cellars, i.e., in spaces where there is an increased risk of CO₂ accumulation.

How to Choose a CO₂ Detector

Always choose CO₂ detectors from verified manufacturers, as cheap sensors may be unreliable. If you want to have complete control over the air quality in your home, opt for models with additional sensors – many CO₂ detectors also measure humidity and temperature, which significantly affect air quality.

For maximum user comfort, choose detectors with a display, where you can always see the CO₂ concentration in real-time. You can also choose whether the detector will alert you to increased CO₂ concentration with a light or sound alarm.

Where to Install CO₂ Sensors

CO₂ detectors contain the sensors themselves and a control unit. The sensors should be placed 10-20 cm above the floor, as CO₂ sinks in the room. The control unit with the display can, of course, be placed at eye level.

When installing, ensure that the detector's sensor is not in a draft, but that air can flow freely to it. It should not be, for example, behind furniture or heavy curtains. Dirt, moisture, and grease can reduce the sensitivity of the sensors, so ensure that the detector is placed in a dry and clean environment.

Advice and Recommendations from Experts

The concentration of carbon dioxide increases rapidly in unventilated spaces due to breathing. Just two people can raise the CO₂ concentration in a living room to a level that can harm your health within a few dozen minutes. Experts therefore recommend regular ventilation and purchasing the aforementioned carbon dioxide detectors.

You can ventilate either by traditionally opening windows or through a controlled ventilation system with heat recovery. Regular ventilation not only improves the air quality in rooms but also ensures a sufficient supply of oxygen to flames if there are gas appliances or boilers indoors. This reduces the risk of the formation of deadly poisonous carbon monoxide (CO).

Even though carbon dioxide is a natural part of the atmosphere, at higher concentrations, it can negatively affect our health and, in extreme cases, even cause death. We therefore always recommend installing a reliable carbon dioxide detector in risk-prone interiors, which will alert you to increased concentrations of this toxic gas in time.