Documented behavior change with Realdania

A controlled study of teaching material and SKYer's impact on the indoor climate in 33 elementary schools over 18 months in a collaboration between ÅBN, Implement Consulting Group and Alinea.

Download the full report here
Billede af Lasse Frost fra Implement Consulting som var konsulent for ÅBN til dokumentation

Tested in collaboration with Implement Consulting Group

Our study shows quite clearly that SKYEN, together with a habit kit, supports new sustainable habits in the classroom, which gives students a healthier indoor climate.

When the CO2 level becomes too high, it starts to have a negative impact on the students' well-being and learning. But with the CLOUD, that is actually eliminated.

Here, a year later, there is no indication that the effect is returning. It's pretty wild.

Lasse Frost
Implement Consulting Group

  • Alinea logo

    Development partner

  • Implement Consulting Group logo


  • Realdania logo

    Financing partner

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Test design

This survey tests knowledge about indoor climate, and is a supportive tool that can lead
for student-engaged behavioral changes. One of these is active ventilation in the classroom over the long term, which thus reduces the CO2 level during the school day. Here teaching material is included which creates focus and learning around the importance of what good ventilation habits and a healthy indoor climate do for students' learning opportunities.

We recruited 125 classes at 33 public and private schools around the country – 10 west of the Great Belt and 23 east of the Great Belt. All schools were interested in investigating the possibilities of improving the indoor climate through behavioral changes in classrooms without mechanical ventilation. The participating classes were in grades 3-5.


Our study shows that it is possible to create lasting indoor climate improvements in Danish schools - even without massive investments in building renovation. After measuring the indoor climate in a baseline, sending educational material and SKYER to randomly selected schools and then following the development for a whole year, we can conclude that we can change behavior and that it makes a difference in relation to creating healthier air in during the school day. Both the teaching material and the CLOUD seem to make a positive difference, but the CLOUD has the biggest and most lasting effect.

Deployed together with a habit kit, SKYEN has enabled a lasting behavioral change among students and teachers that has resulted in the CO2 level exceeding 1000 ppm 1.5 hours a day and virtually never exceeding 2000 ppm. This should be seen in contrast to the baseline measurement, where the CO2 level exceeded 1000 ppm over 3 hours, and was above 2000 ppm for more than 30 minutes every day all year round.

Furthermore, the study also underlines the fact that behavior around ventilation means a lot to the quality of the indoor climate. During the partial school closures as a result of COVID-19, all schools – also in the control group – have had a significantly better indoor climate than usual, also on days when there has been almost normal activity in the smaller classes.

Billede af rapport der dokumentere adfærds effekt på ÅBN SKYEN som ligger på et træbord

Download the report here

The CLOUD, the habit kit and the teaching material can initiate behavioral changes that create lasting improvements to the indoor climate. After 1 year, the students who have been set up with SKY and sent a habit kit in the class stay almost exclusively in acceptable CO2 levels during the school day.

Read the full report here

Download the full report here

Documented behavior change with Realdania. A controlled study of teaching material and SKYer's impact on the indoor climate in 33 elementary schools over 18 months in a collaboration between ÅBN, Implement Consulting Group, Alinea