0.1 mg/litre
1.5 mg/litre
5 mg/litre
10 mg/litre
hardness in water
residual chlorine in water
turbidity in water
dissolved oxygen in water
only (i)
both (i) and (ii)
both (i) and (iii)
all (i), (ii) and (iii)
calcium carbonate
magnesium carbonate
sodium carbonate
calcium hydroxide
2
5
7
10