Usha Müller , 6 May 2021

Virus protection

Do air purifiers remove coronaviruses?

We have been faced with the coronavirus and its impact on our health for more than a year now. Naturally, this has brought with it the question as to how we can protect ourselves against this highly contagious virus. Stadler Form arranged for the ability of its Roger air purifier to filter coronaviruses to be tested by an independent laboratory – and the results were very convincing. All three air purifiers from the Roger family drastically reduce the SARS-CoV-2 viral load in the air within a short space of time.

What do the terms Coronavirus, Sars-Cov-2 and Covid-19 actually mean?

It is important to distinguish between the three terms associated with the coronavirus, namely coronavirus, COVID-19 and SARS-CoV-2, and to use them correctly. The official name for the current coronavirus is SARS-CoV-2 which is short for severe acute respiratory syndrome coronavirus 2. The virus has a strain from the coronavirus family. COVID-19 on the other hand is the disease caused by the virus: in the name, “CO” is short for “corona”, “VI” for “virus” and “D” for “disease”.

Infection with the Coronavirus via the air

In many cases, people can become infected with the SARS-CoV-2 virus via the air, both via droplet infection and also via aerosols contaminated with the virus. Virus particles are emitted into the air when you talk and sneeze but also when you simply breathe in and out. Those viruses fly around in the air and can also settle on surfaces after a certain period of time. If the viruses from the air are breathed in by other people in the vicinity directly or after a certain period of time, they can become infected with the virus.

The viral load in the air is very high, particularly in enclosed spaces with poor ventilation. Regular, frequent ventilation can reduce the viral concentration for a short period of time. However, this should not be the only measure used to reduce coronaviruses indoors as it is not particularly effective. Besides the other well-known measures for preventing infection such as limiting social contact, social distancing, wearing a medical face mask and washing your hands regularly, an air purifier can also improve protection. A powerful air purifier can curb the spread of the coronavirus by removing the viruses from the air, thus reducing the concentration of the virus and with it, the risk of infection.

Roger air purifiers in the Coronavirus test

In this video, Samuel explains the test results of the Stadler Form air purifier Roger with regard to SARS-CoV-2 and explains how we can protect ourselves against the coronavirus.

We arranged for our three mobile air purifiers from the Roger family to be tested in an independent laboratory by Airmid in the UK in order to make certain of their effectiveness against coronavirus. This involved placing the Stadler Form air purifiers in a test chamber with a volume of 28.5 m3 in each case where they were switched on and left running for 60 minutes. The viral load in the air was measured during and after the test period. After 1 hour, Roger little and Roger were found to have reduced the viral load of the air within the chamber by an impressive 99.3%. Roger big – the Stadler Form air purifier for the office and other large spaces of up to 104 m2 – even achieved a purification performance of no less than 99.9%. Stadler Form is therefore one of the first manufacturers of air purifiers for private use to have proven the effectiveness of its devices against the coronavirus.

Reduction of MS2 viruses by air purifier Roger big from Stadler Form (x axis = time in minutes, y axis = viral load in the air in %)

The MS2 virus used in the test is an RNA virus like the SARS-CoV-2 virus. Because of its aerosol properties similar to those of human viruses, its viability and its resistance to disinfection, the MS2 virus is normally used in air purifier tests as a substitute for viruses of a similar size*. As proof was provided of the reduction of the smaller MS2 viruses, it can be concluded that the larger SARS-CoV-2 viruses would also be reduced at least to the same extent.

Roger air purifiers from Stadler Form for virus reduction

The whole family of Roger air purifiers can help reduce the concentration of coronaviruses in the air drastically within just a short space of time. To ensure that the indoor air is purified before you even get home, with Roger and Roger big you also have the facility to control the air quality via an app and, if the air quality deteriorates, to initiate the purification of the air.

Air purifiers as additional protection against Covid-19

According to the United States Environmental Protection Agency (EPA), “when used correctly, air purifiers can help reduce pollutants in the air in residential buildings or enclosed spaces, including viruses.”** An air purifier like Roger can help reduce the risk of viral infections and thus provide the family and anyone else in the house with the best possible protection against becoming infected with the coronavirus. In shops, restaurants and hairdressers, as well as schools and nurseries, a Roger air purifier can also provide children and employees with additional protection against becoming infected with the coronavirus.

Stay healthy!


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*With a diameter of approximately 25 nm, the MS2 virus is more than 4 times smaller than the SARS-CoV-2 virus which has a diameter of 120 nm.

**EPA: “Will an air cleaner or air PURIFIER help protect me and my family FROM COVID-19 in my home?”, 12. Januar 2021 - www.epa.gov/coronavirus/will-air-cleaner-or-air-purifier-help-protect-me-and-my-family-covid-19-my-home