Water for human consumption, which is taken directly from a drinking water installation. For water of this category no protection is necessary.
Category 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 color. 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.
- Water entering houses
- Water entering blocks of flats
- Drinking water supply for office buildings, schools, kindergartens etc.
- Heating systems for drinking water
- Individual safeguard on beverage or coffee machines
Category 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
- Heating water refill (without inhibitors)
- Industrial refilling equipment e. g. cooling systems
- Disinfection equipment in large kitchens
- Flushing and cleaning device for dispensing systems
Liquids 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
- Water supply of chemical laboratories in schools, photo laboratories
- Temporary connection points with standpipes e. g. at fairs
- Refilling equipment e. g. heating systems with additives, cooling systems
- Protection of dosing systems of industrial washing machines and dishwashers
The 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.
- Rainwater systems
- Fire extinguishing systems
- Supply lines in sewage treatment plants
- Agriculture: for the water supply of cattle troughs
- Biological laboratories