From sensors to health: the link between indoor climate and sick absence

Can a better indoor climate help improve health and efficiency at daycare centers? A knowledge bridge project between the Danish Technological Institute, X-Systems and the IoT factory has investigated this. Together, they have uncovered important challenges and opportunities for improvement in the field.

The partners also measured temperature and humidity in relevant rooms, and data was collected over 6 months with sensors from IoT Fabrikken and analyzed at the Danish Technological Institute.

X Systems supplied air purifiers to clean the air and reduce the risk of infection and improve the indoor climate in the institutions. The sensors measured the indoor climate, which was then analyzed by the Danish Technological Institute.

Data collection and process

An important lesson learned from the Knowledge Bridge project was that VOC and CO2 do not always follow each other. Although the Knowledge Bridge project collected a lot of data, the Danish Technological Institute could not see a correlation between indoor climate and virus concentration. However, they have gained valuable insights into the detection and reduction of airborne viruses in e.g. daycare centers.

Many ventilation systems in institutions, for example, are controlled by CO2 concentration and not VOC level, which can be a challenge if you want a good indoor climate.

The Knowledge Bridge project has shown that although the purification and analyzes worked as expected, the virus detection did not pick up enough viruses. This could be due to low virus concentrations, insufficiently collected air or degradation of viruses during collection.

Sensors were installed in common areas (e.g. cloakroom and multi-room) to establish a baseline. Air purifiers were installed and air samples were collected once a week for a period of 5 weeks, while respiratory-related sick leave among employees was recorded weekly for 8 weeks.

The air samples were collected by bubbling air through liquid in a liquid bottle and were then concentrated to be analyzed for viruses at the Danish Technological Institute.

The Knowledge Bridge project enables us to test new research in the real world together with companies and ultimately create value for companies and society. – Freja Rydahl Rasmussen, Consultant for Air and Sensor Technology at the Danish Technological Institute.

The Knowledge Bridge project also highlighted the complexity of detecting airborne viruses and that future studies should consider an increased air collection volume. Another important factor was that the flow rate was too low and that a collection period of 6 hours per 1m3 of air proved inappropriate.

Indoor climate to be investigated on a broader scale

Despite various methodological challenges, the Knowledge Bridge project has created a solid foundation for future studies focusing on indoor climate and sick leave. It is with these experiences from the knowledge bridge project that an application is made to the Working Environment Research Fund on a larger scale with approx. 20 day care centers.

The continuation of the knowledge bridge project into a new project is of great interest among municipalities that also lack knowledge in the area – Freja Rydahl Rasmussen, consultant for Air and Sensor Technology at the Danish Technological Institute.

The upcoming project funded by the Working Environment Research Fund will focus on the connection between indoor climate, well-being, and sick leave, building on insights from the knowledge bridge project.