Monitoring indoor air quality in real time gives the right insights to maintain healthy conditions
Indoor Air quality is important and regulated by law. In a former article we already mentioned how in Belgium, a federal law entered into force last year to regulate indoor air quality standards. However, the current situation, is making it even more critical to be able to monitor and act upon it in order to guarantee healthy environments.
Just a few days ago, the 226 residents of a Quebec nursing home were all contaminated with Covid-19. The virus was present in the air and was found everywhere in the building. How did that happen? The ventilation systems were non-functional in the building and, according to Caroline Duchaine, bioaerosol specialist at Laval University, “the lack of ventilation has undoubtedly allowed the virus to accumulate in the air and settle in places far from infected patients.”
What we know about Corona virus transmission routes
Current data suggest that transmission via air can happen in two ways:
- Close contact transmission through large droplets (> 10 microns), which are released and fall to surfaces not further than about 1-2 m from the infected person.
- Airborne transmission through small particles (< 5 microns), which may stay airborne for longer periods and can be transported long distances. This transmission route is not confirmed by WHO, but based on the precautionary principle, this should be taken into account to manage the ventilation in buildings.
This mechanism implies that keeping 1-2 m distance from infected persons might not be enough and increasing the ventilation is useful because of removal of more particles.
Current Recommendations to limit airborne transmission
When there is no HVAC in place
Following WHO (World Health Organisation) recommendations, it is important to open windows and doors in closed environments (schools, office buildings, etc.) in order to make sure the venue is well ventilated.
When there is HVAC system in place
Following recommendations of the REHVA (Federation of European Heating, Ventilation and Air Conditioning Associations), in buildings with mechanical ventilation systems, extended operation times are necessary in order to remove virus particles out of the building and to remove released virus particles from surfaces. It is therefore advised to start ventilation a couple of hours earlier and switch off later than usual, or to keep the ventilation on 24/7, possibly with lowered (but not switched off) ventilation rates when people are absent.
In Practice: how to monitor indoor air quality in real time?
In order to be able to follow current recommendations, it is important to be able to monitor air quality parameters remotely. In practice, what do you need to do?
During the webinar, three experts will share with you the best practices to put in place, based on current scientific knowledge. In practice, you will learn how to:
- Which data to collect and how to collect it automatically?
- How to analyse indoor air quality and which remote visualisation tools to use?
- How to detect deviations from thresholds in real time? Which alerts can be set in order to identify when ventilation is needed?
Samuel Caillou, Researcher in Building Heating & Ventilation at WTCB-CSTC-BBRI
Geert Bellens, Engineer comfort and indoor climate in buildings at Metiz
Frederic Wauters, Product and Innovation Manager at Energis, expert in digital solutions for energy, comfort and air quality monitoring