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Comparing CO2 levels on two or more monitors
Comparing CO2 levels on two or more monitors

Comparing, CO2

Updated over a week ago

Are you interested in comparing the CO2 levels on your monitors? We are here to help.

  • The CO2 sensor works by automatically adjusting to a weekly baseline in the environment it is in. This means it will take the lowest reading it has had in the past week and this will be the new baseline for 'fresh air'. For this reason, it is important that the 2 (or more) monitors you are comparing have been in the same place and exposed to the same conditions for at least a week. If you compare monitors that have been in different locations, it is possible that they will behave differently when placed in a side-by-side environment.

  • Because CO2 is a gas and gases are not equally distributed amongst an area, the concentration will not be the same in every air sample taken. This is true even if 2 (or more) monitors are placed inches apart. The CO2 sensor also takes samples every 5 minutes, so even if there are a few minutes of difference between the sampling times, this will also affect variances in measurements.

Ready to start comparing two or more monitors? Please follow the steps below.

  1. Start a new measurement segment at the same time with the two monitors side by side. (For steps to start a new measurement segment, click here.

  2. Be sure that the monitors are not only in the same location but are also exposed to the same conditions. (For example, if they are in the same room, are they right beside the other, or is one closer to a source of ventilation?)

  3. Let the monitors run side by side for 7-10 days. During this time, the sensors are still calibrating so it is normal to see a deviation between the two. Towards the end of the calibration time, you will start to see the values converge.

  4. Be sure to place them in a generally well-ventilated room. This will help the sensors establish a good baseline for 'clean air'.

Please note: The CO2 sensor and comparing CO2 values on the sensors should be used for guidance and to get a general idea of the air quality/ventilation within an area. The ideal CO2 levels indoors are under 1000 ppm. If your indoor levels rise above 1000 ppm, you should consider ventilating with fresh air by opening a window or opening a door. CO2 levels above 2000 ppm should be avoided if possible. With prolonged exposure to high levels, you could experience headaches, sleepiness, poor concentration, and increased heart rate. The air will also begin to feel stagnant, stale, and stuffy.

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