New legislation imposes accuracy criteria on CO2 meters sold in Belgium.

Pictogramme représentant un CO2-mètre



You may already have noticed that two CO2 meters placed side by side do not indicate the same values. This inconsistency may be due to the fact that the two devices are not equally accurate.

So how do I know whether the indoor air quality in my room is good, if I can't trust my CO2 meter?

Thanks to legislation introduced by the FPS Public Health, all CO2 meters sold in Belgium must comply with a list of criteria. One of these criteria concerns the accuracy of CO2 concentration measurements. This must comply with a standardised European norm. Another criterion requires, for example, that the device can be calibrated, i.e. the value it measures can be compared with a reference value, to ensure that it is working properly.

As a result, all CO2 meters placed on the market in Belgium after 22 March 2024 will have to measure CO2 concentration in an equivalent way.

Do I have to replace the CO2 meter I'm currently using?

No. This legislation is not retroactive. It does not prevent the use or sale of devices that were already on the market before 22 March 2024.

In all cases :

  • remember to calibrate your CO2 meter regularly, in accordance with the manufacturer's instructions;
  • remember to follow the federal recommendations [FR, NL] in terms of positioning and use of your device.

Incorrect calibration or incorrect use can distort measurements. Reliable CO2 concentration measurements are essential. They give an indication of the indoor air quality in the premises, and therefore of the need to improve it.

► Link to the Royal Decree of 7 February 2024 determining the conditions for the placing on the market of portable and transportable CO2 meters for monitoring indoor air quality [FR/NL]