Achema 2022: Research project examines protective effect of half masks under real conditions of use

FFP2 masks are currently an indispensable part of our everyday lives: they are considered an effective means of protecting against the corona virus. However, the masks were developed for occupational safety in accordance with the applicable test standards. A team of researchers at the Technische Universität Kaiserslautern (TUK) is now investigating the protective effect under real conditions of use in the Covid 19 pandemic - for example, when the mask is exposed to moist breathing air. Does this change the microstructure of the mask? The team will present its project at the Achema process industry trade fair in Frankfurt from 22 to 26 August at the Rhineland-Palatinate research stand (stand A35, hall 6).

FFP2 masks belong to the group of particle-filtering half masks. They play an important role in the Covid 19 pandemic and can protect against infection indoors. "These masks originally come from occupational health and safety and are worn during dusty activities or when handling dusty goods. The masks are tested according to the resulting protection requirements," says Dr.-Ing. Maximilian Kerner, who is responsible for aerosol technology under Professor Dr.-Ing. Sergiy Antonyuk at the Chair of Mechanical Process Engineering at TU Kaiserslautern. "These are clearly different conditions or requirements compared to the actual risk from the coronavirus."

In a current research project, the team around Kerner and Antonyuk is investigating the protective effect of the masks under real conditions of use. A relevant influencing factor is the wetting of the masks with (saliva) droplets in combination with the humidity of exhaled air. How does this change the mask? "We try to transfer the real conditions of mask use into the test," Kerner continues. "For example, what happens when the mask is alternately flown through to mimicinhalation and exhalation - what influence does the resulting deformation or distortion have on the mask and the protective effect?"

In the laboratory, the masks are tested with an enclosed test head. In this setup, such a head is located in a chamber. The test head allows air to flow through it alternately. Solid particles and liquid droplets can be introduced into the air flow. The mask is placed over the mouth and nose of the test head. "We have the possibility to vary the air humidity as well as the particle material and the composition or ingredients of the droplets," explains Kerner. This allows the protective effect to be examined - in terms of whether particles or droplets are retained. "We measure the particle size and concentration in front of the mask or in the ambient air and monitor what arrives after the mask or penetrates the mask," says Kerner.

At the fair, the team will demonstrate the test of the masks with the enclosed test head.

The German Federation of Industrial Research Associations (AiF) is funding the project (IGF project 22382 BG / 1) as part of the programme to promote joint industrial research (IGF) by the German Federal Ministry of Economics and Climate Protection (BMWK). It was launched in May.

Questions can be directed to:
Dr.-Ing, Maximilian Kerner
Chair of Mechanical Process Engineering
E-mail: maximilian.kerner(at)mv.uni-kl.de
Phone: 0631 205-3035

Klaus Dosch, Department of Technology and Innovation, is organizing the presentation of the researchers of the TU Kaiserslautern at the Achema. He is the contact partner for companies and, among other things, establishes contacts to science.
Contact: Klaus Dosch, E-mail: dosch@rti.uni-kl.de, Phone: +49 631 205-3001