Measure and monitor air quality
“What gets measured, gets managed…" (P. Drucker)
“What gets measured, gets managed…" (P. Drucker)
The risk of becoming infected with the COVID-19 virus is higher in crowded and poorly ventilated spaces. Transmission of COVID-19 via aerosols rarely occurs outdoor or in enclosed spaces with a large volume. The general recommendation is to deactivate indoor air recirculation, to increase the supply rate of fresh air and the extraction rate of stale air. The ventilation system should remain active on continuous base.
In case no ventilation system is available, window airing in combination with the monitoring of indoor air quality is recommended. For this purpose, Sentera advises to use CO2 transmitters. When many people share a limited space, the CO2 concentration will increase rapidly. Just like the risk of spreading COVID-19 virus particles. Long before occupants will perceive bad air quality or lack of ventilation, the climate monitoring system will alert you to increase ventilation or to open the window.
IAQ or Indoor air quality is not merely a matter of how the environment feels (temperature and humidity), polluted indoor air has a direct impact on our health and well-being. Depending on the degree of pollution, a poor indoor air quality can cause health problems such as respiratory diseases (e.g. asthma), allergies, and possibly even lung cancer. These symptoms are often summarised under the term SBS or Sick Building Syndrome.
Together with the increased thermal insulation of our buildings, the importance of intelligent ventilation systems is rising in order to maintain a good indoor air quality and to minimize energy losses.
The following parameters have a direct impact on the health, the sense of well-being and the comfort of the residents:
Temperature and relative humidity have a direct impact on the sense of well-being and comfort of the residents.
Dry air leads to dry skin, itchy eyes, and irritated nasal passages. It can cause a bloody nose or an itchy throat and can aggravate symptoms of the common cold and some respiratory ailments. It also increases static electricity, which you feel in your clothes and hair and on furniture and carpeting.
Too high relative humidity degrees will result in condensation forming on windows, walls and ceilings that are colder than the air temperature and potentially damaging building materials and causing odours in poorly ventilated spaces.
Since temperature and relative humidity are the basic parameters determining the comfort and well-being of residents, most Sentera sensors can measure these.
Carbon Dioxide (CO2) - not only a by-product of combustion, it is also the result of the metabolic process in living organisms. Because carbon dioxide is also a result of human metabolism, concentrations within a building are often used to indicate whether adequate fresh air needs to be supplied to the space.
Moderate to high levels of carbon dioxide can cause headaches and fatigue, and higher concentrations can produce nausea, dizziness, and vomiting. Loss of consciousness can occur at extremely high concentrations. To prevent or reduce high concentrations of carbon dioxide in a building or room, fresh air should be supplied to the room.
NDIR is an industry term for “nondispersive infrared”, and is the most common and adequate type of sensor used to measure CO2. CO2 gas molecules absorb the specific band of IR light while letting other wavelengths of light pass through. Finally, an IR detector reads the amount of light that was not absorbed by the CO2 molecules or the optical filter. The difference between the amount of light radiated by the IR lamp and the amount of IR light received by the detector is measured. The difference is proportional to the number of CO2 molecules in the air inside the room.
VOC or Volatile Organic Compounds - The human contribution to indoor air pollutants has been historically correlated with CO2, which is commonly used as an indicator for insufficient ventilation in closed spaces, but this doesn’t cover the complete load.
VOCs or Volatile organic compounds are known to cause eye, nose and throat irritations, headache, drowsiness, dizziness, nausea, difficulty concentrating and fatigue.
VOCs in indoor environments evaporate from substances such as cleaning products, adhesives, paints, new carpets, copiers and printers to building materials and furnishings. VOCs are also emitted from humans and animals in their breath, sweat and directly from their skin.
Therefore, it is important to monitor the VOC levels and to extract the contaminated air from the area.
CO and NO2 - Shopping malls, office buildings, large hotels, event venues … Car parks are increasingly important in large building projects. When cars move around an enclosed parking garage, they release toxic gases like nitrogen dioxides (NO2) and carbon monoxide (CO). These gases must be extracted as soon as they are detected by the CO and NO2 sensors.
Some Sentera HVAC sensors are available with LEDs and a buzzer. The LEDs provide a clear visual indication of the indoor air quality. The green LED is active as long as the measurement stays within range. When the measurement is out of range, a visual alert is given via the yellow LED. In case the measurement reaches the alarm level, the red LED is activated. In case the sensor also has a buzzer, the red LED and buzzer are activated simultaneously. Sentera HVAC sensors are available with 24 V or 230 V power supply. This simplifies the installation in existing buildings. They offer a simple solution to monitor air quality and generate visual or auditory alerts in case extra ventilation is required. Sentera HVAC sensors offer visual indication for temperature, relative humidity, CO2, air quality (TVOC), CO or NO2. The measured values are transmitted via the analogue output(s) and via Modbus RTU. All settings can be adjusted via Modbus RTU.
Sentera also offers intelligent sensors. Their smart algorithm controls a single output based on the measured values. This 0-10V output can directly control an EC fan, an AC fan speed controller or a damper actuator. A typical application is a class room with CO2 sensor. The CO2 sensor directly controls a supply and / or extraction fan. In case the green LED is active, the indoor air quality is good and the ventilation system is active at the minimum level. When the classroom is occupied, CO2 levels increase. Soon the yellow LED will light up and the ventilation rate will increase. The red LED lights up in case the CO2 concentration reaches the alarm level. The ventilation rate will be maximum. The alarm level can be reached in case too many people occupy the classroom or in case of clogged filters.
Install Sentera HVAC sensors in the rooms that you want to monitor. Connect the different sensors via the Sentera PoM concept. The PoM concept simplifies wiring, minimises installation costs and makes installations in existing buildings a possibility.
Use the Sentera internet gateway to simplify the setup of your installation. All devices will automatically receive their own unique Modbus RTU address. Also non-Sentera devices can be added to your installation. It is possible to personalise your installation by adding the location of each device. That will make it easier afterwards to distinguish the kitchen sensor from the bedroom sensor.
Once your installation is set up, you can choose between local visualisation or remote monitoring. For local visualisation only, the internet gateway can be removed. In case you keep the internet gateway installed, all measured values and alerts are remotely available via SenteraWeb. Also data logging during a longer period is possible. This makes it possible to discover trends. The logged data can be displayed in graphs.
Hard to choose? Then combine both: local and remote monitoring of your indoor climate!
In case you keep the internet gateway installed, you have access to SenteraWeb. This makes it possible to monitor and adjust parameters via your computer or mobile device. Also data logging during a longer period is possible.
This makes it possible to discover trends. The logged data can be displayed in graphs.
For each installation, you can define different users and configurators. The users can monitor data, the configurators can adjust settings.
Each sensor in the installation can be given a specific name and location. You can select the most relevant parameters and visualise these on your personal dashboard. Each installation can have a different dashboard. Just select the most relevant information that you want to visualise on the dashboard of your installation.
You can monitor your indoor air quality whenever you want, wherever you want!
No internet connection available? In that case you can add an HMI with 5" colour display to your installation and monitor your indoor air quality locally.
The location of each sensor can be modified to simplify the ease of use. The 4 most relevant parameters for each sensor will be visualised on the home screen. In case one of the parameters is out of range, the pictogram will be highlighted.
Classroom – CO2 monitoring
Fitness room - TVOC monitoring
Waiting room - TVOC monitoring
Wine cellar – temperature & humidity monitoring
Night club - TVOC monitoring
Restaurant – TVOC monitoring