Physico-chemical characteristics of drinking water (ISIRI 2009; WHO 2011)
Parameters . | Unit . | Admissible limit in Iranian standards . | Maximum contaminant level in Iranian standards . | WHO guidelines . |
---|---|---|---|---|
Total hardness | mg/L as CaCO3 | 200 | 500 | 500 |
Calcium | mg/L | 300 | – | – |
Magnesium | mg/L | 30 | – | – |
pH | – | 6.5–8.5 | 6.5–9 | 6.5–8.5 |
Bicarbonate | mg/L | – | – | 150 |
Sulphate | mg/L | 250 | 400 | 250–500 |
Alkalinity | mg/L | – | – | – |
Residual free chlorine | mg/L | – | 0.5–1 | – |
Parameters . | Unit . | Admissible limit in Iranian standards . | Maximum contaminant level in Iranian standards . | WHO guidelines . |
---|---|---|---|---|
Total hardness | mg/L as CaCO3 | 200 | 500 | 500 |
Calcium | mg/L | 300 | – | – |
Magnesium | mg/L | 30 | – | – |
pH | – | 6.5–8.5 | 6.5–9 | 6.5–8.5 |
Bicarbonate | mg/L | – | – | 150 |
Sulphate | mg/L | 250 | 400 | 250–500 |
Alkalinity | mg/L | – | – | – |
Residual free chlorine | mg/L | – | 0.5–1 | – |