Quality Requirements of Drinking Water
| Parameter | Requirements (Desirable Limits) | Undesirable effect when outside permissible limit | Permissible limit in the absence of alternate source |
|
ESSENTIAL CHARACTERISTIC |
|||
| pH | 6.5 – 8.5 | Beyond this range the water will affect the mucous membrane and/or water supply system | No relaxation |
| Colour (Hazen units), maximum | 6.5 – 8.5 | Above 5, consumer acceptance decreases | 25 |
| Odour | Unobjectionable | ||
| Taste | Agreeable | ||
| Turbidity, NTU, Max | 5 | Above 5, consumer acceptance decreases | 10 |
| Total hardness (as CaCO3), Max | 300 mg/L | Encrustation in water supply structure and adverse effects on domestic use | 600 mg/L |
| Iron (as Fe), Max | 0.30 mg/L | Beyond this limit taste/appearance are affected, has adverse effect on domestic uses and water supply structures, and promotes iron bacteria | 1.0 mg/L |
| Chlorides as Cl, Max | 250 mg/L | Beyond this limit taste, corrosion and palatability are effected | 1000 mg/L |
| Residual free chlorine, Min | 0.20 mg/L | ||
|
DESIRABLE CHARACTERISTICS |
|||
| Dissolved solids, Max | 500 mg/l | Beyond this, palatability decreases and may cause gastro intenstinal irritation | 2000 mg/l |
| Calcium (as Ca), Max | 75 mg/l | Encrustation in water supply structure and adverse effects on domestic use | 200 mg/l |
| Magnesium (as Mg), Max | 30 mg/l | 100 mg/l | |
| Copper (as Cu), Max | 0.05 mg/l | Astringent taste,
discoloration and corrosion of pipes, fitting and utensils will be caused beyond this |
1.5 mg/l |
| Manganese (as
Mn), Max |
0.1 mg/l | Beyond this limit
taste/appearance are affected, has adverse effect on domestic uses and water supply structures |
0.3 mg/l |
| Sulphate (as
SO4), Max |
200 mg/l | Beyond this causes
gastro intenstinal irritation when magnesium o |
400 mg/l |
| Nitrates as NO3 | 45 mg/l | Beyond this methane-moglobinemia takes place | 100 mg/l |
| Fluoride, Max | 1.0 mg/l | Fluoride may be kept as low as possible. High fluoride may cause fluorosis | 1.5 mg/l |
| Alkalinity, Max | 200 mg/l | Beyond this limit taste becomes unpleasant | 600 mg/l |
Reference
IS: 10500 – 1992 – DRINKING WATER [SPECIFICATION]
Kya MDD bhi light or heavy compaction me vary hoti he. or koi special case he jisme light ya heavy compaction use karna necessary ho?
Yes. Values of MDD & OMC obtained from light compaction & heavy compaction are different from each other. For embankment construction work, heavy compaction test are preferred over light compaction test.
Hi,
Is omc obtained from light compaction and heavy compaction varies
Yes. OMC obtained by heavy compaction is lesser in value as compared to OMC obtained by light compaction.