When designing, close attention was paid to nose-cheek and below-chin parts. The construction of the scarf insures that there are no gaps, thanks to the overall shape, elements, length and other design characteristics.
When worn correctly, the air should only pass through the area of the Scarf with the nanofiber membrane in the front area.
The material of the filter underwent testing in an American microbiological institute Nelson Labs which tested the level of its filtration efficiency for viruses and bacteria with both of the tests showing 99.9% of filtration efficiency.