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What is The minimum recommended conecntration of free chlorine (mg/L) in drinking water at the end of 1 hour is - and explain in detail?
Recommended contact period of free residual Chlorine in water : 1 hour Level of free residual chlorine (FRC) recommended : Water type Residual chlorine level (Recommended) Contact period Drinking water >0.5 mg per litre (ppm) 1 hour Water bodies, post disaster >0.7 mg per litre (ppm) 1 hour Swimming pool sanitation >1.0 mg per litre (ppm) 1 hour Ref: Park 25th edition Pgno : 752