Table 4.
National AQI classes and concentration ranges of the pollutants (Mahato et al. 2020)
| AQI class (range) | PM10 24-h (μg/m3) | PM2.5 24-h (μg/m3) | NO2 24-h (μg/m3) | NH3 24-h (μg/m3) | SO2 24-h (μg/m3) | CO 8-h (mg/m3) | O3 8-h (μg/m3) |
|---|---|---|---|---|---|---|---|
| Concentration range | |||||||
| GOOD (0–50) | 0–50 | 0–30 | 0–40 | 0–200 | 0–40 | 0–1 | 0–50 |
| SATISFACTORY (51–100) | 51–100 | 31–60 | 41–80 | 201–400 | 41–80 | 1.1–2 | 51–100 |
| MODERATE (101–200) | 101–250 | 61–90 | 81–180 | 401–800 | 81–380 | 2.1–10 | 101–168 |
| POOR (201–300) | 251–350 | 91–120 | 181–280 | 801–1200 | 381–800 | 10–17 | 169–208 |
| VERY POOR (301–400) | 351–430 | 121–250 | 281–400 | 1200–1800 | 801–1600 | 17–34 | 209–748 |
| SEVERE (401–500) | > 430 | > 250 | > 400 | > 1800 | > 1600 | > 34 | > 748 |