The risk assessment carried out by VTT and the dimensioning of air cleaners helped to increase the average volume of clean air in day-care centres. In a study carried out as a part of the E3 project, child morbidity decreased by 18%.
Air cleaning reduces child morbidity at daycare centres, according to a study carried out in the E3 project. To achieve the optimal volume of clean air, there is a need to review the ventilation system. Room air cleaners can be used to provide the necessary amount of clean air in the room as an addition to the ventilation system. There are simple instructions for the use of air cleaners to improve the air quality of individual rooms, but they are not always applicable for dimensioning the air cleaning of different types of spaces and room combinations.
A risk assessment carried out by VTT and the dimensioning of air cleaners helped to double the volume of clean air in the premises of the participating daycare centres of the study and optimally distribute it to reduce airborne exposure. In the intervention carried out as a part of the E3 project, the impact of clean air on the spread of infections was studied in a daycare centre environment, where the significance of airborne transmission as a route of infection is assumed to be lower due to the high impact of contact and droplet transmission. Therefore, a drop of as much as 18% in child morbidity is a significant result.
"To reduce exposure to infections as effectively as possible, it is important to optimise the placement of air cleaners in the rooms and their dimensioning, i.e. the amount of cleaned airflow. The risk assessment carried out in the study considered, among other things, the floor plan of the premises, ventilation, the number of users, usage time, and usage methods," says Inga Ehder-Gahm, Senior Scientist at VTT.
“When surveying the situation, it is important to make sure that ventilation works as planned. Various air cleaning solutions, such as room-specific, portable air cleaners or other air purification solutions, can be used alongside ventilation to add clean air to spaces with the highest risk of infection.”
Ehder-Gahm states that in so-called ‘ordinary' spaces, it is impossible to achieve a completely exposure-free situation, and the purpose of air cleaning is to dilute the amount of airborne contaminants in the level that reduces the risk of infection or, in cases of building-related health issues, the symptoms caused by other exposure agents.
It is also important to take the correct use of air cleaners into account in the practical implementation. In the study, which was carried out in daycare centres, it was found that to ensure the continuity of operations, constant monitoring of the use of devices operating independently of building automation is required.
Based on the study, it can be concluded that optimally placed air cleaning innovations can help societies to protect themselves from airborne infection and reduce the spread of pathogens in places where people meet.
VTT has an important role in one of Finland’s largest projects between companies and research organisations. The key objective of the project has been to develop solutions that will allow the functions of society to continue without interruption and allow people to move and live safely despite the challenges posed by epidemics and pandemics. In addition to the daycare centre study, the information obtained in the project has been applied to, for example, hospital and office environments. “With well-designed and implemented solutions, the safety of different facilities can be bolstered, both against pathogens and other air pollutants,” summarises Aku Karvinen, lead for VTT’s part of the E3 project.
