Correct Answer - Option 4 : 2000
Explanation:
The permissible limit of total dissolved solids (TDS), (in mg/l), in drinking water in the absence of an alternate source, is 2000 mg/l
As per IS 10500 : 2012, the following are the various permissible limits for different parameters:
|
Parameters
|
Acceptable Limit
|
Permissible limit in absence of alternate source.
|
|
Total suspended solids
|
500
|
2000
|
|
Turbidity (NTU)
|
1
|
10
|
|
Colour (TCU)
|
5
|
25
|
|
Taste & odour (TON)
|
1
|
3
|
|
Total dissolved solids (mg)
|
500
|
2000
|
|
Alkalinity
|
200
|
600
|
|
pH
|
7 – 8.5
|
< 6.5 & > 9.2
|
|
Hardness (mg/L)
|
200
|
600
|
|
Chloride content (mg/L)
|
250
|
1000
|
|
Free ammonia (mg/L)
|
0.15
|
0.15
|
|
Nitrate (mg/L)
|
45
|
No relaxation
|
|
Fluoride content (mg/L)
|
1
|
1.5
|
|
lron as Fe (mg/L), max
|
0.3
|
No relaxation
|
|
Sulphate (mg/L)
|
200
|
400
|
|
Calcium (mg/L)
|
75
|
200
|
