• Fresh air supply can be evaluated by examining indoor CO2 concentrations at room level during occupancy. CO2 is a good indicator of the amount of bio-effluents, pollutants from humans, in the air.
  • CO2 emission per person should be set at 20 l/h and 13.6 l/h per person for living rooms and bedrooms respectively (reference: EN 16798-1).
  • The requirements should be met for a minimum of 95% of occupied time.
  • The classification of the air quality is determined as the use-time-weighted hourly average of all room scores.
  • The minimum requirements as specified in national codes should always be followed.



Total average score = total weighted score/total hours use


The total average score is based on multiplying the indoor air quality score for each room with the amount of hours spent and the number of people in that room during a week (weekdays and weekend), then dividing by the total number of people-hours. In case no actual or predicted use numbers are available, use the default use hours in the table below.


This way, the rooms that are being used more intensively will contribute with higher weight.