Table 2. Pore size and cover factor in fabrics of type I masks.

The mean pore size and cover factor was calculated form ten and five measurements, respectively.

Masks	Pore size (mean ± σ) μm	Cover factor (mean ± σ)	Masks	Pore size (mean ± σ) μm	Cover factor (mean ± σ)
M1	394 ± 38	78 ± 4	M7	204 ± 23	82 ± 3
M2	167 ± 26	87 ± 2	M8	197 ± 27	87 ± 1
M3	392 ± 41	79 ± 2	M9	258 ± 27	83 ± 2
M4	370 ± 57	72 ± 9	M10	457 ± 39	66 ± 4
M5	173 ± 19	88 ± 2	M11	138 ± 15	90 ± 3
M6	77 ± 8	94 ± 2	M12	80 ± 9	96 ± 2