Minimise virus concentrations indoors without wasting energy

In the face of the pandemic, many European countries now recommend that classrooms and other rooms in educational institutions refresh the indoor air several times a day to reduce the risk of virus infections over the autumn and winter season.
For instance, in Germany, where the German Federal Environment Agency recommends 5 minutes of airing every 20 minutes for classrooms. Often, the solution is to simply open the windows to let fresh outside air in. That is also what the Agency recommends.
Although it works, it has some significant negative side effects. In particular the loss of heated indoor air during the colder months of the year because opening the windows significantly increases the need for energy to reheat the air indoors. It’s not an environmentally friendly approach. With more than 76 million pupils and students enrolled in schools and pre-schools in the EU and an average of around 20 per class, that’s more than 3 million classrooms potentially releasing a lot of heated air into the open. Money out the window so to speak.
At the same time, we’re amidst a global energy crisis caused by the ongoing war in Ukraine. Prices are soaring and Russian deliveries of gas have dropped, leaving Europe in short supply and with a very uncertain outlook for the autumn and winter season which is rapidly approaching. To illustrate, the average price for natural gas in the EU early September 2022 was six times higher than its 2021 average!
This means that there is every environmental and financial reason to look for alternative ways of ensuring clean and fresh indoor air without wasting any unnecessary energy. At the Dantherm Group, we recommend using professional air cleaners.
Purify heated air – don’t waste it
Air cleaning units such as Heylo HL 400 and Heylo HL 800 renew indoor air quality by constantly filtering the air. To do this, the air cleaners draw in and purify stale air by forcing it through different filters. These effectively remove contaminants and pollutants such as viruses, germs, dust, pollen and allergens from the air to keep conditions fresh indoors.
The technology is highly efficient and cost-effective, as it allows buildings to create and maintain comfortable conditions without letting valuable heat energy escape. Air is simply cleaned continuously and recirculated in the room. In addition, these systems are simple to install as they require no special ducting or ventilation.

Not all air purifiers are effective against COVID-19
While all air cleaners work to clean the air and make the indoor atmosphere healthier, they are not all able to filter corona particles from the air. To do this efficiently, a HEPA H14 filter type needs to be mounted in the unit. The HEPA H14 filter type has been specifically designed to prevent coronavirus particles down to 0.3μm from passing through at a rate of 99% or more. Other types or grades of filters may well be able to filter away dust and other pollutants, but they are most likely not going to be very effective against viral aerosols.
All HEPA H14 class filters used in Heylo units are made in Germany and tested according to the European standard EN 1822, verifiable by their label and serial number. We also have performance certificates from the Fraunhofer Institut, Europe's largest application-oriented research organisation, to confirm the effectiveness of our air cleaners.

Both Heylo HL 400 and HL 800 have been developed and designed with multiple applications in mind to ensure absolute flexibility in their use no matter where they are put into operation. They are particularly popular in buildings and spaces which are densely populated, or where people are gathering for prolonged periods of time. For school classrooms, 2 to 3 HL 800 units will typically be enough to ensure optimal effectiveness and distribution of air across the entire room. Our concept is proven and we have successfully delivered 2,000 HL units that are now in operation across schools in the Free and Hanseatic City of Hamburg.
Discover more about our market-leading air purifying technology by contacting us through the form below.
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