From: Roadside air pollution in a tropical city: physiological and biochemical response from trees
Grade | Score (%) | Assessment category |
---|---|---|
0 | Up to 30 | Not recommended |
1 | 31–40 | Very poor |
2 | 41–50 | Poor |
3 | 51–60 | Moderate |
4 | 61–70 | Good |
5 | 71–80 | Very good |
6 | 81–90 | Excellent |
7 | 91–100 | Best |