Table 1.
Hourly average indoor and outdoor PM2.5 concentrations and infiltration efficiencies (Finf) calculated with portable HEPA filter air cleaners operating and not operating in the library’s media room.
| Date Range (s) | Median Outdoor Conc., µg/m3 (25%–75%) 1 |
Indoor Location | Median Indoor Conc., µg/m3 (25%–75%) 1 |
Infiltration Efficiency | N 1 |
|---|---|---|---|---|---|
| 8/24/19 to 10/16/19 | 23.3 (12.0–49.1) | Inside library | 15.0 (9.8–21.2) | 0.45 | 140 |
| Media room (HEPA operating) | 5.7 (5.5–8.5) | 0.17 | |||
| 8/20/19 to 8/22/19 & 10/18/19 to 11/26/19 |
30.7 (12.2–85.9) | Inside library | 19.6 (9.8–36.2) | 0.31 | 609 |
| Media room (HEPA not operating) | 20.0 (10.5–39.0) | 0.32 |
1 Number of hours included. Used only hours with paired indoor-outdoor data.