20.09.2021

CO₂ and its Influence on Cognitive Performance

CO₂ research has come a long way in recent years. Unfortunately, we still know far too little about the influence of the CO₂ content in indoor air. As one of the leading scientists aptly said: “We have learned a lot and we still know less.” 

However, what has been proven by experiments and studies is that the assumed guideline value of 5,000 parts per million (ppm) was much too high. Today, the critical limit is considered to be more in the range of 1,000 ppm.

What is CO₂ and where does it come from?

Carbon dioxide or CO₂ is the same odourless and invisible gas that is the cause of global warming. We breathe in oxygen and exhale carbon dioxide. This does not only apply to humans, but to all living beings and even plants. In addition, the gas is released into the atmosphere by industry and traffic. Whenever fossil fuels are burned, more carbon dioxide is released into the air. 25% of global emissions originate from transportation. The air we breathe in has as much or even more influence on our mental and physical state than foods or drinks – we need oxygen much more. We spend most of our lives indoors, whether at work, at home, at school or when travelling. Children and people with pre-existing medical conditions are particularly affected by excessive CO₂ levels. To date, little attention has been paid to air quality in these environments. The new threat of viruses and diseases has put the focus on air hygiene. However, very few people know about the quality of their air.

Effects of CO₂ on Cognitive Performance and Concentration

Today, we know that concentrations between 1,000-2,000 ppm negatively affect our cognitive abilities. Moreover, these concentrations have a negative impact on our health and can lead to headaches, nausea, fatigue and serious damage. We all know the feeling of sitting in a meeting with many colleagues in a confined space for extended periods of time. At some point, the air is used up and it is difficult to absorb information and make decisions. This is largely due to the increased CO₂ concentration. As proven in the study, the cognitive abilities of the test persons are reduced by 15% at a carbon dioxide concentration of 945 ppm and by as much as 50% at 1,400 ppm. When indoor CO₂ levels are high, people are less satisfied, report more acute health symptoms, work more slowly and are more likely to be absent from work or school. Especially in our latitudes, ventilation unfortunately is too rare due to the cold temperatures. In addition, buildings are so effectively insulated that there is no air exchange.

You are what you breathe!

The easiest way to reduce CO₂ concentrations is fresh air. We are able to subjectively judge whether a room is freshly ventilated or the air is stale. However, at that point, the values usually already are far above the CO₂ concentration that is good for humans. Those who don’t want to lose their performance and concentration even after an eight-hour working day should measure the CO₂ concentration. Employers also greatly benefit from good air quality. Health-related leaves and generally impaired work performance harm the company. A portable meter benefits everyone, especially in meeting rooms.

The Indoor CO₂ Traffic Light

There are a number of measuring devices on the market today. They are no longer reserved for research, but designed for private use. One of the most accurate ways to measure carbon dioxide is co₂go: https://co2go.eu/pages/shop. It can be connected to a smartphone or computer and measures the values in real time. It also creates a graph and analyses the air quality. This data is then used to make recommendations and create trends. The device fits in a pocket and only has three small lights. Green means good, yellow critical and at red windows should be opened for ventilation immediately. With this device, not only the concentration level can be increased, but health can also be positively influenced.

Carbon Dioxide (CO₂) is Considered the Most Important Value for Air Quality

In fact, the CO₂ concentration in many rooms is much higher than in the atmosphere. In addition, in some buildings – such as offices, hospitals and schools – there are many people exhaling carbon dioxide. We are CO₂ machines. An increased concentration of CO₂ in indoor spaces can be harmful to our bodies and minds. Anyone who has been sitting in a car for a long time knows the feeling of exhaustion and how good it feels to open the window and exchange the stale air. Life-threatening microsleep is not only a symptom of overtiredness, but can also be triggered by stale air. Yawning is a way to get more oxygen to the brain and is not solely due to tiredness. Fresh air can also increase concentration and positively influence the cognitive performance at work. If our body is not supplied with enough oxygen, it can lead to downright suffocation of the brain. Over the last 200 years, the CO₂ concentration in the atmosphere rose from about 280 parts per million before the industrial revolution to about 410 parts per million today. As a result, decision-making processes are affected. Governments have paid little attention to indoor air quality in the past. In doing so, it is possible to create clean, germ-free air in buildings and public indoor spaces. The first step is to provide people with more information. Sensors and meters that detect indoor CO₂ levels can provide useful data on when windows should be opened or a ventilation system should be serviced. To do this, however, it is necessary to know the air quality. Standardised guiding values for indoor carbon dioxide levels could help. Air certificates for buildings (similar to food hygiene certificates) could ensure clean air in the future. The most common complaints triggered by bad air include: Headache, fatigue, shortness of breath, cough, dizziness, nausea and irritation of eyes, nose, throat and skin. According to the New York Times, in recent years, at least eight studies have examined how the atmosphere in rooms with many people changes over an extended period of time. In addition to physical conditions, the cognitive performance is impaired as well. People in healthy, fresh air have been shown to be more attentive and better able to solve mathematical problems, for example. All of these are more than sufficient reasons to pay more attention to air quality. Fresh air can reverse the stress caused by high CO₂ concentrations and provide compensation. If you wait until you are tired and can no longer focus, it is already too late.