| Grade | AQI | Value |
| Level 1: Excellent | 0 - 50 | 3 |
| Level 2: Good | 51 - 100 | 4 |
| Level 3: Mild pollution | 101 - 150 | 5 |
| Level 4: Moderate pollution | 151 - 200 | 6 |
| Level 5: Heavy pollution | 201 - 300 | 2 |
| Level 6: Severe pollution | Above 300 | 1 |