The protection against viruses depends on the particle size of the aerosols containing infectious viruses. The sizes of these virus-containing particles differ from just the naked virus diameter (0,02–0,03 µm) to the sizes of the carrier particles. According to a study of the influenza virus, the virus-containing particles vary largely in size and 5% of the particles where larger than 4 µm, 75.5% was 1–4 µm and 19.5% smaller 1 µm. In another study of FMDV, 65–71% of the virus-containing particles were over 6 µm in diameter, 19–24% was 3 - 6 µm and 10–11% were under 3 µm. 

The Urban Air Mask 2.0 and Lite Air Mask is tested and certified for 98% protection against particles down to the size of 0.3µm and because of this, the mask will protect you against virus-containing particles that are larger than 0.3µm. 

Our Urban Air Mask 2.0 and Lite Air Mask is KN95 (Chinese standard) certified which is similar to FFP2 (European standard) and N95 (US standard) which most governments and authorities recommend during Corona. Please see the comparison between them here.

However, note that no mask can guarantee full safety and protection agains viruses.