"There is clear evidence that the common adoption of chlorination of drinking water supplies in the 20th century was responsible for a substantial decrease in infectious diseases." (Source 1)
Water is essential for life. It’s used everywhere – in home settings, “out and about” in institutions, commercial properties and industry, and in agriculture. It is essential that this water be of a quality suitable for its intended use.
Water can be home to many pathogens. Of most concern to human health are pathogens released into water upon contamination with human or animal waste. If this water is drunk, used for cooking, washing up, showering, bathing or brushing teeth, pathogens can enter the body and cause illness.
The World Health Organisation estimates that access to safer water could prevent, annually:
Not only does hygienic drinking water save lives and prevent suffering caused by illness, it also promotes economic prosperity by increasing productivity and saving on health care expenditure. In Australia, where access to safe water is the norm, it is easy to take this basic need for granted. But approximately one in eight people in the world lack access to safe drinking water.
Air conditioning: The potential build-up of pathogens such as the bacterium Legionella in cooling water systems, such as air conditioning cooling towers, is an important water safety issue in Australia. As the air conditioner pumps cold air into the building, these pathogens can potentially be inhaled by the building inhabitants.
Waste water: Another aspect of safe water is removal of waste water. This is discussed under waste management.
Hygienic water means ensuring that the levels of pathogens, chemicals and organic matter in water are safe for its intended use. The more contact the water will have with humans, the more stringent the requirements for its quality.
Towns and cities in Australia are connected to water reticulation or distribution systems, consisting of water mains, pipes, reservoirs, pumps and valves. These systems provide clean, safe water to homes, schools, hospitals, businesses, care facilities, restaurants and industry at the turn of a tap. Water in these systems can come from:
Smaller towns and rural settings may rely on private dams and rainwater tanks for their water needs.
All water requires treatment before it is used. The level of treatment required depends on the quality of the incoming water and the intended use of the treated water. Addition of specific water treatment chemicals is a vital part of this process, as is regular monitoring or water quality. See the diagram below for a summary of the water treatment process.
Other chemicals which may be added during water treatment include:
Click here for a more extensive list of water treatment chemicals recommended by the National Health & Medical Research Council
Air conditioning: There are two important aspects to maintaining the safety of cooling tower water. Firstly, regular cleaning is needed to remove corrosion products, rust, scale, slime, sludge, mould, algae, biofilm and fungi from pipes and storage units. Secondly, maintenance of an effective concentration of disinfectant chemical is required, with the exact type of treatment depending on the source of the cooling water and the materials used for the cooling system.
I&I water treatment chemicals play a vital role in both of these aspects.
Source 1: Australian Drinking Water Guidelines 2004, www.nhmrc.gov.au/guidelines/publications/eh34
Source 2: WHO 2008, “How does safe water impact global health?” www.who.int/features/qa/70/en/index.html