Before Covid-19, no one was aware of the consequences of contamination through aerosols. These solid or liquid microscopic particles swirl around us in gas and can plague our airways.
Ventilation is crucial to combat aerosol contamination. In an article published in the journal Science, a team of 39 scientists called on governments to pay more attention to ventilation systems.
Just open the damn window!
We have heard this advice non-stop for months. Fresh air can reduce the flow of aerosols, especially if you open two windows at the same time.
Sometimes though, it is not feasible to open the window all the time, let alone two windows simultaneously.
In some environments, windows cannot open for safety reasons, such as banks, psychiatric institutions and prisons. Other buildings require constant temperature and humidity, such as museums. In many modern office buildings, windows are unable to open at all. A lack of windows demands the use of a different ventilation system.
Ventilating with outside air is not always a good idea, for example, if the room is next to a busy road. The chance of fine dust coming in from outside is very high. That fine dust, which may seem harmless, is harmful to your health in large quantities.
The problem with ventilation systems
Mechanical ventilation systems focus on moving the air, causing aerosols to re-circulate. Such systems often work with filters. Filters that remain infrequently cleaned frequently are themselves a breeding ground for bacteria. Hence, we end up in a vicious circle.
Even the best HEPA filters still allow contamination to pass through. These filters filter fine dust down to a size of 0.3 microns, which is not enough to filter micro-particles smaller than 0.1 microns out of the air. The same applies to particles that we breathe out.
Some of the particles we breathe out will evaporate, reducing their size and causing them to float. These floating aerosols cause contamination in an enclosed space, especially when we talk loudly, cough or sneeze.
In 2021, buildings will increasingly have to comply with strict insulation standards, which will not help ventilation. We create mould and moisture, and we have to install systems for that. Most ventilation systems are also not strong enough to entirely remove contaminated air, particularly in crowded rooms.
The discussion around CO2 meters
Besides fine dust, carbon dioxide (CO2) is also a problem. Every time you breathe out, CO2 is released. A high value in a room indicates that ventilation is insufficient. The Taskforce Ventilation is talking about an upper limit of 900 ppm. At least one square metre of open window per four people in a room would be required.
Hospitality and fitness establishments have recently been obliged to hang up a CO2 meter. Schools should also do so. Earlier this year, a Canadian father’s covidecolesquebec.org went viral after he could prove through a large-scale experiment that the use of CO2 meters and ventilation systems in schools could help reduce the number of cases of Covid-19.
Simple air cleaning with UV light
A CO2 meter alone will not improve the air, only alert you to a problem. Having a completely new ventilation system installed is costly and not always feasible.
That is why a system based on ultraviolet light is a good investment, especially in spaces where many people come together, and the ‘turnover’ is high. Think of schools, offices, catering establishments, medical environments etcetera
The efficiency of UV light, especially the Ultraviolet C variant, has been demonstrated several times. Various techniques are possible, including upper-room systems where the device hangs at the top of the room and free-standing appliances suitable for smaller spaces.
Infralia’s UVC systems have been officially deemed safe and approved for use in indoor spaces by the Federal Public Health Authority and Task Force Covid19.
Questions? Please let us know!