face mask

In this work we investigate the bidirectional filtration efficiencies of respirators, such as FFP2 masks and medical masks, under cyclic breathing and different fits. We developed a test bench, which consists of a test chamber with an artificial head, and which is connected to a specially developed artificial breathing function. The exhalation filtration performance of masks can be evaluated by exhaling particle-laden air into the test chamber. Similarly, the inhalation filtration performance can be evaluated by inhalation of particle-laden air from the test chamber.

Airborne exposure has been highlighted during the COVID-19 pandemic as a probable infection route. This experimental study investigates different protection methods at an office workstation, where the concentration characteristics are studied under mixing ventilation conditions. The protection methods were the room air purifier, personal air purifier, face mask, and workstation partition panels. In experiments, the breathing machine, nebulizer, and syringe pump were used to generate an aerosol distribution of paraffin oil in the room.