Hygienically perfect drinking water is our most important foodstuff and a basis for our health. Plumbers, planners, contractors, users and everyone else should always keep this fact in mind.
This means that all negative influences on the quality of our drinking water - such as lead, legionella, chemical and biological impurities, to mention just a few - must therefore be avoided under all circumstances.
Deterioration of drinking water quality can occur, among other things, due to faulty piping installations, contact with unsuitable materials, stagnation in less used pipeline sections and heating (i.e. PWC and PWH pipes are perhaps too close together or not properly insulated). If these factors are ignored in a drinking water installation, the growth of bacteria is pretty much a given.
This can lead to damage to health and even endanger life and limb.
SANHA® piping systems fully meet the high demands placed on the material used. Depending on the application and the quality of the drinking water, we have systems available from various types of stainless steel, copper, lead-free silicon-bronze copper alloy (CuSi) and/or plastic. Therefore we are able to provide a solution that meets the requirements and guarantees optimum protection of the drinking water quality when it comes to material.
Besides the material used, the installation itself, the "lay of the land", plays a very important role. In addition to the correct selection of hygienic materials and system components, a system design that is coordinated with hygiene is of course a basic pre-requisite for the quality, durability and sustainability of any and all drinking water installation.
In recent years, scientific studies have made it increasingly clear that bacteria from drinking water are far more responsible for infections than previously suspected.
For this reason, engineers, installers and everyone else involved must increasingly focus on this "microbiological problem" in order to ensure hygienically perfect, pure drinking water at the tapping points at all times.
The following explanations are intended to give the planner and plumber a general overview of the leading bacteria relevant for drinking water installations, hygienic installation methods and professional commissioning.
The importance and necessity of a responsible, continuous and intensive cooperation between planners, plumbers, contractors and so on is essential in the planning and execution of a drinking water installation. Self-evident, you say?
Yes and no. We all know that mails get lost, time constraints haunt us all or whatever else you can think of from your day to day experience. We're all humans at the end of the day!
Having said this, the importance of cooperation cannot be emphasized often enough. Not only does it take a lot of diligence, there is also a lot at stake.
Everybody knows the phenomenon: all those involved actually work well together, but when it comes to a section or sub-project, everyone assumes that the other person is responsible or cares - and then nobody cares.
This is easy to avoid - and everyone, whether planner, installer, construction manager or client, should be aware of this in advance. After all, most national Infection legislation stipulates that "water for human consumption must be of such quality that its consumption or use does not cause any harm to human health, particularly through pathogens" (this is translated from the German law but applies to almost every country).
The installation includes not only the pipes and fittings, but also the shut-off valves, water storage tanks, taps, fittings and much more. It is a matter of the correct type of installation (e.g. loop installation with double wall panels), the guarantee of sufficiently high temperatures during operation, the observance of a minimum period for water exchange, geodetic height, simultaneity factor, etc. and the responsibility for this lies primarily with the plumber and the planner.
The selection of the piping system, measures for hygiene during installation and expert knowledge during the installation itself are indispensable in order to prevent bacteria in the pipeline network from being supplied with additional nutrients.
The materials used in the pipng system play an important role in this regard. The materials used in the pipelines can release nutrients in the form of organic carbon compounds (DOC = dissolved organic carbon). These also contribute to bacterial growth. The German Federal Environment Agency (UBA) takes this into account in its publications on the hygiene assessment of materials that come into contact with drinking water. The following UBA guidelines and recommendations that have been published up to date include, and resemble equivalent norms elsewhere, are:
Lubricant guidelines as well as the Minority Guidelines are used to evaluate substances that occur in small quantities and do not normally enter drinking water. This includes catalysts and initiators, surface treatment of yarns and fabrics, solvents for additives and other auxiliary materials.
Especially when using organic materials, it must be ensured that they do not provide a breeding ground for microorganisms. Such organic materials include EPDM seals. All organic materials used by SANHA® for sealing rings therefore undergo regular chemical and microbiological testing at the MPA testing facilities in Dortmund in accordance with DVGW Code of Practice W 270.
This ensures that only the highest quality materials are used in SANHA® installation systems and that there is no negative impact on drinking water quality.
SANHA® offers the materials and fittings for every application and drinking water quality that enable installers and planners to realise hygienic, durable, environmentally friendly and sustainable drinking water installations.
In addition to our proven piping systems made of stainless steel, copper and plastic, we also offer various piping systems with press and transition fittings made of high-quality lead-free silicon bronze (CuSi).
As is well known, the best installation avoids stagnation (see also points 8 and 9). Planners and installers have many fittings and connection options available for a stagnation-free (or low stagnation) installation:
This makes it easy to perform a hygienic loop installation with low pressure loss. All fittings are equipped with the appropriate press, thread or plug ends and can be connected directly to stainless steel, copper or plastic composite pipes, which ensures a cost-effective, safe and efficient installation.
Especially our double-walled plates made of CuSi offer a clean and safe solution, which is ideal for drinking water installations not only due to its particularly high dezincification capability but also due to the lead-free material.
As in the planning and installation of drinking water systems, the leakage/pressure test must be carried out with absolute hygiene awareness.
A leak test with water must not be carried out if longer stagnation periods are to be expected after the pressure test, pipes cannot be completely emptied, pipes cannot be pressed with water due to the effect of frost or if pipes must be tested for reasons of construction progress but cannot be put into operation afterwards.
If one assumes that a leak test must usually be carried out so that the pipes can be finally insulated and the walls can be finished, a longer stagnation phase following the leak test can generally be assumed, even in the case of a single-family house.
A hygienically perfect leak test is therefore only possible in the form of a "dry test" with oil-free compressed air or inert gas (nitrogen or carbon dioxide). This test must be carried out in two steps, namely the leak test (preliminary test) and the subsequent strength test (main test).
The leak test is performed with a test pressure of 15 kPa (150 mbar). The test time is at least 120 minutes up to 100 litres of line volume. The test time is extended by 20 minutes for each additional 100 litres of line volume. The pressure gauges used must be calibrated and allow a reading accuracy of 0.1 kPa (1 mbar).
The strength test is carried out at 300 kPa (3000 mbar) up to a pipe dimension of DN 50 inclusive. For pipe dimensions larger than DN 50, the test pressure shall be 100 kPa (1000 mbar). The test duration is 10 minutes - during this time no pressure drop must be detectable. The pressure gauges used for this test must also be calibrated and allow a reading accuracy of 0.1 kPa (1 mbar).
1] The basic idea behind the simultaneity factor is that peak demand is not called up simultaneously in all residential units.
