If the Water Is Cloudy

If the water contains visible particles, it should first be pre-filtered or allowed to settle before further treatment.

Pre-filtration

Water can be pre-filtered through a coffee filter, preferably a double layer, or through a tightly woven cloth. The purpose is to remove larger particles before further treatment.

Settling

If the water contains sand or other heavier particles, leave it undisturbed for a few hours so that the particles can settle to the bottom. A tall, narrow container can help the particles settle more effectively.

The pre-filtered or settled water can then be made safer to drink by:

• boiling
• ceramic filtration
• chemical disinfection
• a combination of filtration and chemical disinfection

Boiling

Boiling is a highly effective way of killing disease-causing bacteria, viruses and parasites. Bring the water to a rolling boil before allowing it to cool. At high altitude, where water boils at a lower temperature, a longer boiling time may be advisable.

Ceramic Filtration

Ceramic filters have very small pores and can effectively remove many bacteria and parasites. Viruses, however, may be small enough to pass through some filters.

Depending on the type of filter, additional chemical disinfection may therefore be appropriate after filtration. Always follow the manufacturer's instructions for the particular water filter you are using.

Chemical Disinfection

Cloudy water should be filtered or allowed to settle before chemical disinfection whenever possible. The effectiveness of chemical disinfectants depends on the product used, the quality and temperature of the water and the required contact time.

Water Purification Tablets

Water purification tablets containing substances such as chlorine or iodine can be used in some situations. Always follow the manufacturer's instructions carefully, including the recommended dose and contact time.

Iodine-containing products may not be suitable for everyone, including pregnant women and people with certain thyroid conditions, and are generally intended for short-term or emergency use.

Chlorine-Based Disinfection

Chlorine-based products can be used to disinfect water when suitable commercial products are available. The concentration of the active ingredient varies between products, so the correct amount cannot be determined from the product name alone. Always follow the manufacturer's instructions or recognised public health guidance for the specific product being used.