The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here:

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Jakob Löndahl

Jakob Löndahl

Associate Professor / Senior Lecturer

Jakob Löndahl

Indoor model simulation for covid-19 transport and exposure


  • Tareq Hussein
  • Jakob Löndahl
  • Sara Thuresson
  • Malin Alsved
  • Afnan Al-Hunaiti
  • Kalle Saksela
  • Hazem Aqel
  • Heikki Junninen
  • Alexander Mahura
  • Markku Kulmala

Summary, in English

Transmission of respiratory viruses is a complex process involving emission, deposition in the airways, and infection. Inhalation is often the most relevant transmission mode in indoor environments. For severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the risk of inhalation transmission is not yet fully understood. Here, we used an indoor aerosol model combined with a regional inhaled deposited dose model to examine the indoor transport of aerosols from an infected person with novel coronavirus disease (COVID-19) to a susceptible person and assess the potential inhaled dose rate of particles. Two scenarios with different ventilation rates were compared, as well as adult female versus male recipients. Assuming a source strength of 10 viruses/s, in a tightly closed room with poor ventilation (0.5 h−1 ), the respiratory tract deposited dose rate was 140–350 and 100–260 inhaled viruses/hour for males and females; respectively. With ventilation at 3 h−1 the dose rate was only 30–90 viruses/hour. Correcting for the half-life of SARS-CoV-2 in air, these numbers are reduced by a factor of 1.2–2.2 for poorly ventilated rooms and 1.1–1.4 for well-ventilated rooms. Combined with future determinations of virus emission rates, the size distribution of aerosols containing the virus, and the infectious dose, these results could play an important role in understanding the full picture of potential inhalation transmission in indoor environments.


  • Ergonomics and Aerosol Technology
  • NanoLund: Center for Nanoscience

Publishing year





International Journal of Environmental Research and Public Health





Document type

Journal article




  • Environmental Health and Occupational Health
  • Infectious Medicine


  • Expiratory droplet
  • Indoor aerosol modeling
  • Inhaled dose
  • SARS-CoV-2




  • ISSN: 1661-7827