Water

Water used should be clean and reasonably free from deleterious materials such as oils, acids, alkalies, salts etc. Potable water is commonly considered satisfactory. Water should be tested for the subsequent features:

Limits of Acidity

To neutralise 200 ml sample of water, it should not needed more than 2 ml of 0.1 normal caustic soda solutions.

Limits of Alkalinity

To neutralise 200 ml sample of water, it should not needed more than 10 ml of 0.1 general hydrochloric acid.

Percentage of Solids

It should not exceed the following limits for several solids :

Organic          200 mg/l

Inorganic       3000 mg/l

Sulphates       500 mg/l

Chlorides       2000 mg/l

Suspended matter   2000 mg/l

The pH Value

The pH value of water shall generally be not less than 6.