Table 2.

Air permeability of composite materials and disposable face masks (± standard deviation). KF––kraft fibers, HF––hemp fibers, and FF––fungus fibers.

Sample	ISO 5636-3 mL/min	EN 14683 Pa/cm2	ISO 9237 mm/s
KF	8275 ± 491	355 ± 21	17 ± 1
HF	32 ± 2	4.3 × 105 ± 2.5 × 103	<1
FF	6935 ± 323	445 ± 26	13 ± 1
KF FF	23990 ± 965	91 ± 5	65 ± 4
HF FF	77 ± 2	1.4 × 105 ± 8.4 × 103	<1
KF HF FF	115 ± 10	8.5 × 104 ± 5 × 102	<1
Disposable face masks	65,054 ± 13,324	26 ± 7	241 ± 63