Hardness of drinking water should be?: (A) >3, (B) <1, (C) 3-Jan, (D) >6
Answer is C. Drinking water should be moderately hard.Softening of water is recommended if hardness ecxeeds 3mEq/l. Soft water- <1 mEq/l Moderately hard- 1-3 mEq/l Hard water- 3-6mEq/l Very hard water- >6mEq/l Parks textbook of preventive and social medicine.K Park. Edition 23.Pg no: 727