Facemasks
White facemask
Blue facemask
Green facemask
Surface area (cm2)
305 cm2
260 cm2
285 cm2
Number of layers and compositions
One layer of electret medium between two layers of polymers
One layer of mechanical medium between two layers of polymers
One layer of woven cotton fabric (thread count: 120)
Fiber diameters
External:
42 ± 4 µm
Medium:
10 ± 5 µm
Internal
42 ± 4 µm
External:
60 ± 5 µm
Medium:
15 ± 6 µm
Internal
52 ± 5 µm
25 ± 10 µm
Images (1600×)
External: 
Medium: 
Internal: 
External: 
Medium: 
Internal: 
