Sr No
Category of
parameter
Characteristics
Analytical method
Unit
BIS Max. Permissible limit (1998)
1
General
pH
Electrode
6.5 - 8.5
2
EC
Conductivity meter
µS/cm
3000
3
TDS
TDS meter
mg/L
2000
4
Total hardness
(as CaCO3)
EDTA titrimetric
mg/L
600
5
Major cations
Sodium (Na+)
Flame photometric
mg/L
200
6
Potassium (K+)
Flame photometric
mg/L
10
7
Calcium (Ca2+)
EDTA titrimetric
mg/L
200
8
Magnesium (Mg2+)
EDTA titrimetric
mg/L
100
9
Major anions
Bicarbonates (
)
Titrimetric
mg/L
NA
10
Chlorides (Cl−)
Titrimetric
mg/L
1000
11
Nitrates (
)
Titrimetric
mg/L
45
12
Sulfates (
)
Barium chloride
mg/L
400
13
Boron (B)
Curcumin method
mg/L
?
14
Irrigation water quality
Salinity
%
NA
15
SAR
?
<10 or 10 - 18
16
RSC
meq/L
<1.25
17
%Na
%
<20 or 20 - 40
18
PI
%
Class 1 or 2
19
KI
?
<1.0
20
MH
%
Below 50%
21
SSP
?
NA