Table 1 Face masks under investigation.

This table lists the investigated face masks, mask alternatives, and mask material (masks are depicted in Fig. 2). Masks marked with an asterisk (*) were tested by four speakers; all others were tested by one speaker.

Mask, nameDescription
1, “Surgical”*Surgical mask, three layers
2, “Valved N95”N95 mask with exhalation valve
3, “Knitted”Knitted mask
4, “PolyProp”Two-layer polypropylene apron mask
5, “Poly/cotton”Cotton-polypropylene-cotton mask
6, “MaxAT”One-layer Maxima AT mask
7, “Cotton2”Two-layer cotton, pleated style mask
8, “Cotton4”Two-layer cotton, Olson style mask
9, “Cotton3”Two-layer cotton, pleated style mask
10, “Cotton1”One-layer cotton, pleated style mask
11, “Neck Gaiter”One-layer polyester/spandex, 0.022 g/cm2
12, “Bandana”*Double-layer bandana, 0.014 g/cm2
13, “Cotton5”*Two-layer cotton, pleated style mask
14, “Fitted N95”N95 mask, no exhalation valve, fitted
“Swath”Swath of mask material, polypropylene
“None”*Control experiment, no mask