The method used for cleaning water by using chlorine tablets is to dissolve one tablet of 4 mg for every litre of water and keep the bottle closed for 10 minutes. Then open the bottle and consume the water, as all bacteriological contaminants will be dead.
Two advantages of using chlorine tablets are
1. These tablets are convenient to carry, particularly for the military in camps or by hikers.
2. It is a safe and effective method, as all bacterial contaminants are killed