Drinking water standards as per Indian Standards are as follows;
S.No
Parameter
IS: 10500 Requirem ent
(Desirable limit)
Undesirable effect outside the desirable limit
IS:10500 Permissible limit in the absence of alternate source
Essential Characteristics
1pH6.5 - 8.5Beyond this range the water will effect the mucous membrane and / or water supply systemNo relaxation
2Colour (Hazen Units), Maximum5Above 5, consumer acceptance decreases25
3OdourUnobjectio nable----
4TasteAgreeable--
5Turbidity, NTU, Max5Above 5, consumer acceptance decreases10
Following Results are expressed in mg/1 :
6Total hardness as CaCO3, Max300Encrustation in water supply structure and adverse effects on domestic use600
7Iron as Fe, Max0.3Beyond this limit taste/appearance are affected, has adverse effect on domestic uses and water supply structures, and promotes iron bacteria.1
8Chlorides as Cl, Max250Beyond this limit tast, corrosion and palatability are effected1000
9Residual, Free Chlorine, Min0.2----
Desirable Characteristics
10Dissolved solids, Max500Beyond this palatability decreases and may cause gastro intentional irritation2000
11Calcium as Ca, Max75Encrustation in water supply structure and adverse effects on domestic use200
12Magnesium as Mg, Max30--100
13Copper as Cu, Max0.05Astringent taste, discoloration and corrosion of pipes, fitting and utensils will be caused beyond this1.5
14Manganese as Mn, Max0.1Beyond this limit taste/appearance are affected, has adverse effect on domestic uses and water supply structures0.3
15Sulphate as SO4 Max200Beyond this causes gastro intentional irritation when magnesium or sodium are present400
16Nitrates as NO345Beyond this methanemoglobinemia takes place100
17Fluoride, Max1Fluoride may be kept as low as possible. High fluoride may cause fluorosis1.5
18Phenolic compounds as C6H5OH, Max0.001Beyond this, it may cause objectionable taste and odour0.002
19Mercury as Hg, Max0.001Beyond this, the water becomes toxicNo relaxation
20Cadmium as Cd, Max0.01Beyond this, the water becomes toxicNo relaxation
21Selenium as Se, Max0.01Beyond this, the water becomes toxicNo relaxation
22Arsenic as As, Max0.05Beyond this, the water becomes toxicNo relaxation
23Cyanide as CN, Max0.05Beyond this, the water becomes toxicNo relaxation
24Lead as Pb, Max0.05Beyond this, the water becomes toxicNo relaxation
25Zinc as Zn, Max5Beyond this limit it can cause astringent taste and an opalescence in water15
26Anionic detergents as MBAS, Max0.2Beyond this limit it can cause a light froth in water1
27Chromium as Cr6+, Max0.05May be carcinogenic above this limitNo relaxation
28Ploynuclear aromatic hydrocarbons as PAH, Max--May be carcinogenic--
29Mineral Oil, Max0.01Beyond this limit undesirable taste and odour after chlorination take place0.03
30Pesticides, MaxAbsentToxic0.001
31Radioactive materials----
a) a emitters Bq/1, Max0.1
b) P emitters Pci/1, Max1
32Alkalinity, Max200Beyond this limit taste becomes unpleasant600
33Aluminum as Al, Max0.03Cumulative effect is reported to cause dementia0.2
34Boron, Max1--5