Table 1 Particle concentrations averaged over the exposure periods for each year of the study (Means ± standard deviations)
| Â | 2017 | 2018 | 2019 | |||
|---|---|---|---|---|---|---|
Particle Number (cm−3) | Particle Mass (µg m−3) | Particle Number (cm−3) | Particle Mass (µg m−3) | Particle Number (cm−3) | Particle Mass (µg m−3) | |
Purified Air | 10 ± 20 |  ≤ 5 | 12 ± 5 |  ≤ 5 | 83 ± 3 | 3.5 ± 0.3 |
Ambient Air | (1.1 ± 0.1) × 104 | 18 ± 1 | (1.5 ± 0.1) × 104 | 30 ± 8 | (1.3 ± 0.1) × 104 | 27 ± 0.2 |
PM2.5 | (8.6 ± 2.0) × 104 | 130 ± 5 | (9.5 ± 2.0) × 104 | 123 ± 11 | (8.3 ± 0.5) × 104 | 110 ± 2 |