Ilpo Kulmala This email address is being protected from spambots. You need JavaScript enabled to view it., Kimmo Heinonen, Satu Salo 

Technical Research Centre of Finland VTT Ltd., 33720 Tampere, Finland


Received: February 26, 2021
Revised: March 25, 2021
Accepted: March 26, 2021

 Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

Download Citation: ||  

  • Download: PDF

Cite this article:

Kulmala, I., Heinonen, K., Salo, S. (2021). Improving Filtration Efficacy of Medical Face Masks. Aerosol Air Qual. Res.


  • Filtration efficiency of face masks can be drastically increased by corona charger.
  • improvement could be achieved without significant increase in breathing resistance.
  • battery operated charger power consumption is very low, 70 mW.
  • results may help develop novel type respiratory protectors.


A simple unipolar positive corona charger was constructed and tested with five different medical face mask materials. Charging of particles significantly increased the filtration efficiency of each of the tested face mask against submicron particles. On the average, the increase in the efficiency was from 58% to 93% for 0.3 µm size particles. This improvement was achieved with practically insignificant increase in the pressure drop showing that there are possibilities to fully exploit the potential of electret materials. However, the corona discharge generates ozone which is an issue that needs to be taken into consideration. The results are important when developing efficient protective solutions against airborne threats.

Keywords: Medical face mask, Filtration efficiency, Charging, Bioaerosols

Don't forget to share this article 


Subscribe to our Newsletter 

Aerosol and Air Quality Research has published over 2,000 peer-reviewed articles. Enter your email address to receive latest updates and research articles to your inbox every second week.

Aerosol and Air Quality Research (AAQR) is an independently-run non-profit journal, promotes submissions of high-quality research, and strives to be one of the leading aerosol and air quality open-access journals in the world.