Sodium (%)

Water class

Range (% samples)

<20

Excellent

7.29 - 19.82 (54.05% sample)

20 - 40

Good

22.02 - 39.11 (24.32% sample)

40 - 60

Permissible

41.27 - 57.87 (8.11% sample)

60 - 80

Doubtful

60.09 - 78.90 (10.82% sample)

>80

Unsuitable

2.70% sample)