Drinking water is our most important resource. It is needed every day for drinking, cooking and washing. However, in order to keep it clean and hygienic, and therefore harmless to health, it must be protected in the pipes of the drinking water systems. A vital factor for a hygienically clean water supply is the protection of the drinking water in the pipeline system from contamination by non-drinking water. This is governed by the standard DIN EN1717 Drinking water protection and water hygiene according to EN1717.
DIN EN1717 divides all liquids into five categories based on the potential hazards for the person who might be exposed to this water. It also establishes the need for safeguarding to guarantee reliable drinking water protection.
Category 1 (Drinking water)
Category RequirementsWater for human consumption, which is taken directly from a drinking water installation. For water of this category no protection is necessary.
Category 2 (altered drinking water, no health hazard)
Category requirementsCategory 2 fluids do not pose a threat to human health, but are different from category 1 drinking water in terms of smell, taste, temperature or colour. A category 2 fluid must be at least protected by an EA type backflow preventer. Liquid foods such as tea, coffee, juice etc. belong to liquid category 2 as well as saline fluids or drinking water after preparation or disinfection etc.
Applications:
Category 3 (moderate health hazard)
Category requirementsCategory 3 fluids may present a moderate health hazard to humans through the presence of one or more toxic substances and therefore must be secured, for example, by means of a CA type system separator or a GA type pipe separator. Examples of category 3 liquids are bathwater (in the domestic area), heating water without inhibitors or dishwashing water
Category 4 (strong health hazard, non-biological)
Category requirementsLiquids which can cause serious health hazards to humans due to the presence of toxic, radioactive, mutagenic or carcinogenic substances are assigned to liquid category 4. In this case, the protection is provided, for example, via a GB type pipe separator or a BA type system separator. The category 4 fluids include heating water with additives, swimming pools in the domestic area with automatic water treatment and disinfection, as well as water from high pressure cleaners with cleaning additives
Category 5 (severe health hazard, biological)
Category requirementsThe highest protection requirement is placed on category 5 fluids. These fluids can present a significant health hazard to humans as they may contain microbial or viral pathogens of communicable diseases. This is the case with swimming pools in public/commercial areas as well as with rain water and fire extinguishing systems.
