Chemical Disinfection

Chemical disinfection is the most widely used method of disinfecting drinking-water.

Chlorine Compounds

How to use to Treat 1L of Drinking-water:

For typical room temperature and water temperature of 25°C (77°F), minimum contact time should be 30 minutes. Contact time needs to be increased for colder water; e.g. one hour for temperatures less than 10°C
Prepare tablets according to package instructions
Household bleach (5%) - 4 drops per 1L water
Sodium dichloroisocyanurate - 1 tablet per package instructions; 15mg per 1L of clear water.
Calcium Hypochlorite (1%) - 4 drops per 1L

Can Treat:

Kills most bacteria and viruses
Longer contact time required to kill Giardia cycts - especially when water is cold
Not effective against Cryptosporidium

Iodine - not recommended for pregnant women, or for more than a few months continuous use

How to use to Treat 1L of Drinking-water:

For typical room temperature and water temperature of 25°C (77°F), minimum contact time should be 30 minutes. Contact time needs to be increased for colder water; e.g. one hour for temperatures less than 10°C
Prepare tablets according to package instructions
Tincture of iodine (2%) - 5 drops per 1L
Iodine solution (10%) - 8 drops per 1L
Triiodide or pentaiodide resin - per package instructions

Note: Carbon filter should be used to remove excess iodine after iodine treatment

Can Treat:

Kills most pathogens
Longer contact time required to kill Giardia cycts - especially when water is cold
Not effective against Cryptosporidium

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