C/P

Significance

<0.1

Very slight contamination

0.10 - 0.25

Slight contamination

0.26 - 0.50

Moderate contamination

0.81 - 0.75

Severe contamination

0.76 - 1.0

Very severe contamination

1.1 - 2.0

Slight pollution

2.1 - 4.0

Moderate pollution

4.1 - 8.0

Severe pollution

8.1 - 16.0

Very severe pollution

>16

Excessive pollution