Table 2.
Summary of indoor PM2.5 concentration by season and indoor environments (n = 64).
| Classification | Subgroups | Number (Person-Days) |
Mean ± SD (µg/m3) |
p-Value * |
|---|---|---|---|---|
| All | 9321 | 28.7 ± 24.3 | ||
| Season | Spring | 2093 | 28.0 ± 24.8 | - |
| Summer | 2443 | 20.8 ± 15.0 | <0.0001 | |
| Fall | 2781 | 22.9 ± 19.3 | <0.0001 | |
| Winter | 2004 | 47.1 ± 29.6 | <0.0001 | |
| Indoor RH | <40% | 2748 | 36.5 ± 28.1 | - |
| 40–60% | 5057 | 26.0 ± 23.3 | <0.0001 | |
| ≥60% | 1516 | 25.5 ± 21.7 | <0.0001 | |
| Indoor temperature | <25.5 °C | 4570 | 35.4 ± 27.4 | <0.0001 |
| ≥25.5 °C | 4751 | 22.3 ± 18.7 | ||
| Air purifier | (−) | 785 | 39.9 ± 28.2 | <0.0001 |
| (+) | 8429 | 27.8 ± 23.7 |
* ANOVA test for season and RH and z-test for others; RH, relative humidity.