Table 2.

Filter penetration

	NIOSH test (84 L/min)	Latex sphere tests (6 L/min)
Mask	0.3 μm NaCl	0.8 μm	2 μm	3.1 μm
A	90.2 (0.43)	81.7 (1.51)	77.2 (1.33)	67.4 (0.28)
B	52.9 (2.4)	14.7 (4.36)	4.18 (0.83)	0.62 (0.23)
C	77.2 (1.2)	53.6 (2.31)	43.8 (2.06)	37.8 (2.38)
D	5.98 (0.3)	0.10 (0.02)	0.01 (0.003)	0.0005 (0.0005)
E	37.4 (0.4)	1.55 (0.31)	0.28 (0.05)	0.10 (0.03)
F	28.9 (0.7)	0.53 (0.12)	0.08 (0.02)	0.02 (0.01)
G	10.44 (0.8)	0.11 (0.06)	0.04 (0.03)	0.04 (0.03)
H	3.96 (0.2)	0.04 (0.02)	0.006 (0.006)	0.02 (0.02)
I	31.6 (1.1)	0.51 (0.11)	0.08 (0.02)	0.02 (0.01)

NOTE. Data are in percentage, mean and standard error.