Water quality - a shared responsibility
Why should I disinfect my (drinking) water?
The water supplied by the water supplier is in principle always of good quality. However, drinking water companies cannot guarantee the quality at the tapping point (tap/shower), because they have no impact on what happens in the pipes within your building. Especially in pipes (and buffer tanks) where the water flows slowly or stands still for a long time, the germs present can develop quickly. This water may therefore be contaminated and contain considerable concentrations of germs or pathogens. These pathogens can be bacteria, viruses or parasites (e.g. E-coli, Campylobacter, Salmonella, Legionella, Giardia and Cryptosporidium). Contaminated water can lead to serious reactions such as gastrointestinal disorders and other complications.
See also related articles
How to disinfect drinking water (in your building)
Disinfection kills or removes pathogens from drinking water, thereby reducing health risks. The type of disinfection and water treatment can vary depending on the process in which the water is used. The most common disinfection technologies can be divided into chemical and mechanical disinfection. Examples of chemical disinfection are: chlorine, hydrogen peroxide, ozone and chlorine dioxide. Mechanical disinfection can take place via UV technology and filtration.
Chlorine is a widely used disinfectant for the disinfection of water. It has the advantage of being cheap and being able to kill most disease-causing bacteria and viruses. Chlorine is unable to fully penetrate and break down the biofilm, making it less effective against organisms such as Pseudomonas and Legionella. Chlorine reacts with organic material to form disinfection by-products (e.g. trihalomethanes), which in high concentrations have negative effects on health.
Hydrogen peroxide is a strongly oxidising disinfectant and more powerful than chlorine, for example. However, high concentrations are needed for effective disinfection, which is why they are often not permitted for long-term (continuous) use.
Chlorine dioxide (ClO2) is widely used for disinfection and for controlling taste, odour and algae in drinking water. On top of this, ClO2 also helps remove iron and manganese from drinking water. ClO2 has a high solubility in water and remains in solution as a dissolved gas. As a result, ClO2 has the ability to penetrate the biofilm, remove it and kill the bacteria, viruses and protozoa present throughout the entire piping system.
Ozone: Is an effective water treatment that is often used to reduce colour, taste and odour problems. Ozone is highly reactive, so it reacts away quickly and therefore has no residual action throughout the pipe network. This makes ozone suitable for short pipe systems, but it proves inadequate in practice.
UV technology: does not so much kill micro-organisms, but damages DNA and proteins so that they do not replicate. With this technology the UV light must hit the micro-organisms, which is why it is not applicable to large flow rates. UV technology works very locally and is therefore mainly applied at the water tapping point (e.g. tap or shower).
Filtration: UF (Ultra Filtration) and RO (Reverse Osmosis). With UF a hollow fibre membrane is used to retain dirt particles and microscopically small contaminants of the order of 0.001 – 0.1 µm. UF is a filter system, while RO is a process in which molecules are separated (e.g. removing salt from water).
Conclusion
There are many available water treatment technologies, each with their advantages and disadvantages. Often a combination will lead to an optimal result.
See also related articles
Safe sanitary pipes with minimal disinfection products
Legionella in hot water and cold water pipes
Alternative Legionella management in hot water systems
Harmful bacteria in water
Legionella symptoms, Veterans disease
Effects of materials on biofilm formation in water pipes
How does chlorine dioxide work?
Many types of Legionella bacteria?
Process water or cleaning water must also meet drinking water quality standards
For more information about water disinfection in buildings and installations, contact our specialists at the following number: +32 (0)51 31 43 93 or send your question to our contact form.
← Back to all articles
