New publication on the estimation of the infection risk by aerosol-bound viruses in ventilated rooms

paper Copyright: © EBC

Dirk Müller et al. have published a paper on the estimation of the infection risk by aerosol-bound viruses in ventilated rooms. This publication is based on the publication „Vereinfachte Abschätzung des Infektionsrisikos durch aerosolgebundene Viren in belüfteten Räumen“ and „Empfehlung zum erforderlichen Luftwechsel in Innenräumen zur Reduzierung eines aerosolgebundenen Infektionsrisikos des SARS-CoV-2-Virus“ by Dirk Müller et al.

The previous work was supplemented by the introduction of the expected value for the source strength, the comparison with other risk assessments, a derivation of the linearization of the Welles-Riley model, an extension of the transient calculation and the introduction of a relative aerosol concentration for the evaluation of air purifiers.

Title: Abschätzung des Infektionsrisikos durch aerosolgebundene Viren in belüfteten Räumen

Authors: Dirk Müller, Kai Rewitz, Dennis Derwein, Tobias Maria Burgholz, Marcel Schweiker, Janine Bardey, Peter Tappler



Release of the RisiCo web app for calculating an aerosol-borne infection risk in indoor spaces

Logo Web App Copyright: © EBC

A web app has been developed at the Chair of Building and Indoor Climate Technology that enables the calculation of an aerosol-bound infection risk in individually adjustable indoor situations.

The results of the calculation can be displayed in easy-to-read graphics. The model on which the calculation is based was presented in the previously published papers "Vereinfachte Abschätzung des Infektionsrisikos durch aerosolgebundene Viren in belüfteten Räumen“ and „Empfehlung zum erforderlichen Luftwechsel in Schulen, Großraumbüros, Hörsälen und Turnhallen zur Reduzierung eines aerosolgebundenen Infektionsrisikos“ by Dirk Müller et al.

The web app can be used to assess the infection risk of indoor situations and the effectiveness of infection control measures such as air changes, mouth-nose coverings and air cleaners.

The tool can be accessed at:


New publication on the recommendation for the required air exchange in indoor rooms to reduce aerosol-bound infection risks of the SARS-CoV-2 virus

Diagram air exchange rate Copyright: © EBC

Together with other researchers, the EBC has extended the model for estimating the risk of infection through aerosol transmission by an absolutely assessable reference scenario and by the use of medical face masks and air purifiers, as well as by a transient consideration of indoor air quality. This publication can contribute to the evaluation of necessary measures to reduce the risk of aerosol-bound infection in indoor spaces.

Link to the publication (in German)

Partners: Heinz Trox Wissenschafts gGmbH, Institute for Occupational, Social and Environmental Medicine, RWTH Aachen University, IBO Innenraumanalytik OG, Vienna, Federal Environment Agency, Department II 4.1 Grundsatzfragen der Luftrein-haltung, Fraunhofer Institute for Building Physics IBP


Publication on modeling the risk of infection by aerosol transmissions of the SARS-CoV-2 virus in ventilated indoor spaces

paper Copyright: © EBC

Together with a colleague from Heinz Trox Wissenschafts gGmbH, the EBC has investigated the risks of aerosol transmission of SARS-CoV-2 viruses indoors. This paper, titled "Simplified assessment of the risk of infection by aerosol-bound viruses in ventilated rooms", focuses on the transmission of viruses through aerosols, since this transmission path cannot be reduced by simple measures such as medical face masks and/or observing proper hygiene rules.

The concentration of aerosols contaminated with viruses is directly influenced by the room ventilation. In this contribution to the discussion, Professor Müller and his team analyze complex transportation processes through aerosols to enable an assessment of infection risks in different rooms and operational situations. The focus is on the parameters that can be technically influenced in order to better asses the circumstances where infection risks exist and to identify the room-types where special precautions should be taken to prevent infection.

Link to the publication (in German)

Partner: Heinz Trox Wissenschafts gGmbH


RWTH Aachen and the Luisenhospital support Viessmann in the development of a simple ventilator

Ventilator Copyright: © EBC

At the beginning of the pandemic, the heating and air-conditioning technology company Viessmann decided to develop a simple ventilator using standard modules available in the company and, if necessary, to produce it in large quantities.

The Allendorf-based company was supported in this by a team from EBC, among others, which in turn worked closely with physicians from the Aachen Luisenhospital and scientists from the Chair of Medical Information Technology (MedIT) at the RWTH Aachen University.

In this project, the EBC developed and set up measurement technology and measuring systems in a very short time, with the help of which the prototypes constructed by Viessmann could be tested in detail.

Link to the press release

Partners: Viessmann, Aachener Luisenhospital, Chair of Medical Information Technology (MedIT) at RWTH Aachen University


Rewitz, Kai © Copyright: EBC


Kai Rewitz

Chief Engineer, Team Leader


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