Cabin Air Quality

A cabin full of people can quickly increase the level of CO2. This can lead to drowsiness that we do not notice until we experience physical symptoms. The same problem can arise in vehicles like trains, buses, and aeroplanes. There are existing Climate Control Sensors that can monitor the CO2 concentration in the cabin of a vehicle. At the same time, these measurements make it possible to increase the efficiency of the air conditioning system, thus reducing energy use.

Why measure CO2 in cabins?

Cars, subway trains, and aeroplane cabins are becoming increasingly well-sealed. The CO2 concentration in a vehicle varies depending on the number of people in it. For example, the concentration in a fully occupied cabin can quickly become critical. Therefore, we have to ventilate.

High levels of CO2 can cause tiredness and a lack of concentration, which can be dangerous. In the case of a driver falling asleep at the wheel, the situation quickly becomes very serious.

It is also necessary to ventilate to ensure a healthy indoor environment in vehicles. Even small cabins can hold many people per m3. Bad air quality increases the likelihood of catching viruses, bacteria, and other small particulates. When the CO2 level is 3000 ppm, every 18th breath will contain reused air. Could better air quality in cabins have prevented some Covid-19 cases? We strongly believe so. An Italian study of air quality shows that ventilation can cut COVID-19 cases by 82%. Also, The American Society of Heating, Refrigerating, and Air Conditioning Institute (ARI) stresses the key role that ventilation and recirculation of indoor air plays in reducing the transmission of COVID-19.


Freon gas and ammonia are the most frequently used refrigerant systems, particularly in cars. However, CO2 is becoming preferred as it is non-combustible and is much less harmful to the environment. Of course, any gas leak has to be detected quickly.

How does it work?

An empty vehicle has a concentration of about 400 ppm (normal outdoor concentration). The CO2 concentration in the car, aeroplane, subway, or train will increase for each person added. Therefore, the best choice for optimal efficiency is using a system of Demand Controlled Ventilation. Demand Controlled Ventilation means that sensors are measuring the CO2 value constantly and sending a signal to the ventilation system that changes the level of the ventilation to compensate.

Reduced costs

Thanks to the reduced need for constant ventilation, a Demand Controlled Ventilation system helps the vehicle save energy. Engineers calculate fuel savings of up to 10% when the system is operating in maximum cooling mode. This is both a financial and environmental saving.

Well-controlled ventilation also makes the air healthier, which saves money based on not having to send people to hospitals for cases of CO2 poisoning or other air quality related illnesses.

Fewer traffic accidents caused by drowsiness also reduces the damage caused to people, roads, buildings etc. that can be affected in an accident.

Key Benefits:

  • Healthy cabin air environment
  • Energy savings
  • Positive environmental impact
  • Reduced risk for driver drowsiness