How often should the windows in a room be opened?

To limit the risk of airborne contamination.

The room and the guests

Surface of the room    m2
Ceiling height    m
Number of adults  
Number of children  

Ventilation of the room

 None or poor (ACH = 0.5)
 Medium (ACH = 3)
 Good (ACH = 6)
 Excellent (TRH = 12)




RECOMMENDED INTERVAL TO HAVE EXCELLENT AIR RENEWAL



RECOMMENDED INTERVAL TO HAVE GOOD AIR RENEWAL



CO2 level after one hour without opening the windows



Which corresponds to the following air quality:






How reliable is this calculator ? Below, an example

For more information on French Environment code, please consult nousaerons.fr/infographic.