TABLE 4.
Days with Indoor and Outdoor PM2.5 Above EPA NAAQS and WHO 24 h Standards
| Outdoor PM2.5 |
Indoor PM2.5 |
|||
|---|---|---|---|---|
| Sampling days | Days with PM2.5 > 35 μg/m3, n (%) | Sampling days | Days with PM2.5 > 35 μg/m3, n (%) | |
| All facilities | 1249 | 53 (4.2) | 1326 | 28 (2.1) |
| Wildfire season | 491 | 52 (10.6) | 478 | 28 (5.9) |
| Non-wildfire season | 758 | 1 (0.1) | 848 | 0 (0) |
| Facility 1 | 331 | 22 (6.6) | 322 | 5 (1.6) |
| Facility 2 | 329 | 18 (5.5) | 332 | 15 (4.5) |
| Facility 3 | 313 | 5 (1.6) | 336 | 1 (0.3) |
| Facility 4 | 276 | 8 (2.9) | 336 | 7 (2.1) |
| Sampling days | Days with PM2.5 > 25 μg/m3, n (%) | Sampling days | Days with PM2.5 > 25 μg/m3, n (%) | |
| All facilities | 1249 | 81 (6.5) | 1326 | 37 (2.8) |
| Wildfire season | 491 | 76 (15.5) | 478 | 37 (7.7) |
| Non-wildfire season | 758 | 5 (0.7) | 848 | 0 (0) |
| Facility 1 | 331 | 29 (8.8) | 322 | 10 (3.1) |
| Facility 2 | 329 | 25 (7.6) | 332 | 18 (5.4) |
| Facility 3 | 313 | 14 (4.5) | 336 | 1 (0.3) |
| Facility 4 | 276 | 13 (4.7) | 336 | 8 (2.4) |
Abbreviations: EPA NAAQS, United States Environmental Protection Agency National Ambient Air Quality Standard (35 μg/m3 of PM2.5 for a 24 h period); Wildfire Season, July through October; PM2.5, fine particulate matter; WHO, World Health Organization (standard is 25 μg/m3 of PM2.5 for a 24 h period) Only sampling days with >12 h of hourly data are included in the table.