|
| Single factor pollution index | Pollution degree | Integrated Pollution Index | Pollution degree |
| 1 | Pi < 1 | Cleaning | Pn ≤ 0.7 | Safety |
| 2 | 1 ≤ Pi < 2 | Light contamination | 0.7 < Pn ≤ 1 | Alert level |
| 3 | 2 ≤ Pi < 3 | Medium contamination | 1 < Pn ≤ 2 | Light contamination |
| 4 | Pi ≥ 3 | Heavy contamination | 2 < Pn ≤ 3 | Medium contamination |
| 5 |
|
| Pn > 3 | Heavy contamination |