CO2 sensor is a kind of gas sensor used to measure the concentration of carbon dioxide gas in atmospheric environment.
It is measured in “parts per million” (ppm), usually around 400ppm.
Carbon dioxide, a colorless, odorless gas, has long been considered one of the main “greenhouse” gases affecting Earth’s atmosphere. This gas, along with methane, nitrous oxide and fluorinated gases, forms a barrier in the upper atmosphere that allows heat to be retained. This will lead to higher temperatures, rising sea levels and changes in land use.
CO2 is created during respiration, combustion, and organic decomposition, and is also found indoors. This is a result of both external atmospheric CO2 and internal production from the presence of people.
How do CO2 sensors work?
CO2 can be detected and measured through different technologies, including
nondispersive infrared (NDIR) monitors the absorption of infrared light at a specific wavelength (4.3 μm), a wavelength at which CO2 has very strong absorption. If the infrared light is absorbed, then CO2 is present, whereas non absorption indicates a lack of CO2. The more infrared light that is absorbed the higher the concentration of CO2.
photoacoustic spectroscopy subjects a sample to pulses of electromagnetic energy that is tuned specifically to the absorption wavelength of CO2. With each pulse of energy, the CO2 molecules within the sample will absorb and generate pressure waves via the photoacoustic effect. These pressure waves are then detected with an acoustic detector and converted to a usable CO2 reading through a computer or microprocessor.
Electrochemical carbon dioxide sensors measure electrical current to determine how much CO2 is present in the air. When CO2 enters the sensor, it chemically reacts within a polymer surface, resulting in an electrical charge. The type and amount of electrical charge is then used to determine how much CO2 is present.
NDIR CO2 sensors have performance advantages over other detection technologies due to long-term stability, accuracy, and low power consumption for CO2 measurement.
3 Benefits of Using a CO2 sensor
By collecting and analyzing the monitored data from the CO2 gas sensors companies can quickly and efficiently identify the potential build-up of CO2 in their offices and indoor spaces.
Combining the sensors with Demand Controlled Ventilation (DCV), a company will be able to automatically regulate airflow within the office to respond to CO2 concentrations at any given time. This both provides a better work environment but also saves energy as the ventilation systems will only be operating when needed.
The three key benefits of measuring CO2 levels with sensors and ventilating accordingly are:
1) a healthy and safe working environment with CO2 levels managed to be within the accepted and healthy range of less than 1000ppm
2) improved productivity as the proven impact on cognitive skills from elevated CO2 concentration is alleviated
3) energy-savings through optimized use of ventilation systems
Wrapping up CO2
Carbon Dioxide is a potentially harmful gas when present in elevated concentrations. Its detection and dispersal are essential to stop a number of unhealthy and productivity-reducing conditions for employees.
The early detection of rising CO2 levels, using IoT-based wireless CO2 sensors, allows an organization to respond quickly and to take preventative measures long before harmful levels affect employee health and wellbeing.