TABLE. Mean aerosol concentrations and standard deviations measured at the mouth of each simulator over 60 minutes at varying HEPA air cleaner locations, by masking status — United States, 2021.
| Simulator/Masking status | Mean aerosol concentrations at four HEPA air cleaner locations, % (SD) |
||||
|---|---|---|---|---|---|
| No air cleaner | Left and right (elevated) | Left and right (floor) | Front and back (floor) | Center of room (floor) | |
|
No masks
| |||||
| Participant A |
99.8 (28.3) |
62.1 (8.2) |
61.0 (2.9) |
40.7 (8.4) |
33.3 (1.5) |
| Participant B |
105.8 (7.7) |
45.2 (1.7) |
48.6 (1.9) |
43.8 (1.2) |
41.9 (1.4) |
| Speaker |
94.4 (12.6) |
44.7 (0.9) |
33.4 (1.8) |
50.0 (10.5) |
30.8 (1.1) |
|
Participants and speaker combined*
|
100.0 (12.1)
|
50.7 (3.3)
|
47.7 (1.6)
|
44.8 (5.7)
|
35.3 (1.3)
|
|
Universal masking
| |||||
| Participant A |
31.2 (2.4) |
22.5 (9.2) |
33.1 (4.0) |
12.2 (3.6) |
10.9 (2.3) |
| Participant B |
32.7 (3.9) |
13.7 (3.5) |
11.4 (0.9) |
13.4 (4.5) |
12.8 (2.7) |
| Speaker |
21.7 (2.2) |
7.3 (0.7) |
6.8 (0.7) |
8.1 (2.7) |
5.1 (1.2) |
| Participants and speaker combined* | 28.5 (2.8) | 14.5 (4.3) | 17.1 (1.7) | 11.2 (3.6) | 9.6 (2.1) |
Abbreviations: HEPA = high efficiency particulate air; SD = standard deviation.
* The values for participants and speaker combined represent the average of the results for the two participant receivers and the speaker receiver.