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/ Water quality regulations


                                      EUROPEAN WATER QUALITY REGULATIONS

                                      Regular flush                               Training
                                      According to the French, German and English   Understanding the problems associated
                                      regulations, water stagnation (in sanitary installations,   with bacterial growth in water systems helps to limit
                                      mixers and taps) is a key factor in bacterial   the risk of contamination.
                                      contamination. The European standard EN 806 5   Although French legislators have not yet focused
                                      requires that those sections of the installation that   on training those responsible for the water system,
                                      are used infrequently should be flushed at regular   it is embedded and pursued in Germany
                 Stagnation prohibited
                                      intervals. The recommended interval is once a week.  (with three training levels, depending on the level
                                      All public and commercial buildings are affected,   of responsibility) and in the United Kingdom
                                      in particular schools and council buildings during the   (with personnel competency and training
                                      school holidays, campsites out of season, unoccupied   programmes monitored by the Water Safety Group).
                                      hospital rooms, etc.
                                                                                     Training those responsible
                                      The German Directive of April 2013 (updated in   helps to control bacterial
                                      2023), Hygiene in Drinking Water Installations    proliferation.
                                      VDI/DVGW 6023, requires purging to be carried out
                                      after 72 hours of stagnation in a sanitary installation
                                      (this also includes WC cisterns).
                 Bypass prohibited                                               Circulating loops
                                      Note that the water in the bypass is not sufficiently   A circulating loop up to the point-of-use is not
                                      renewed. They are therefore prohibited.    recommended. It doubles the length of the pipework
                                      If an installation is not used for 72 hours, rigorous
                                      protocols are put in place. DELABIE sees this as a step   and therefore doubles the water volume. The biofilm
                                                                                 surface is increased and, as a result, also the risk of
                                      forward and offers technical solutions to meet this   bacterial development. Moreover, it makes it difficult
                                      requirement (see opposite: electronic water controls).
                                                                                 to maintain high temperatures at all points in the
                                                                                 circulating loop.
                                           The German directive requires         Finally, it also makes it difficult to keep the pipe run
                                           purging to be carried out             volume to less than the 3 litres recommended by
                                           after 72 hours of stagnation.         European directives. Indeed, if the water temperature
                 Measuring pressure                                              in a circulating loop is less than 50°C or 55°C
                                                                                 (depending on the country), the water volume
                                      Undersized pipework                        in the circulating loop must be included in the 3 litre
                                      The German regulation strictly prohibits oversized   maximum calculation.
                                      pipework because they promote bacterial growth
                                      by reducing the water velocity.                A circulating loop up to the point-
                                      DELABIE, along the same lines, recommends slightly
                                      decreasing the diameter of the pipes to increase   of-use is not recommended.
                                      the water velocity to 2 m/sec. (likewise the French
                                      regulation (DTU) recommends 1.5 m/sec.).
                                      This measure prevents the excessive development    Building Management Systems
                 Measuring the temperature  of biofilm and helps to reduce the risk of contamination   Contrary to popular belief, Building Management
                                      without increasing noise levels.           Systems are not recommended by European
                                                                                 directives as they can be complicated, difficult
                                                                                 to handle and extremely costly and do not take away
                                               Oversized pipes are
                                                                                 liability if a problem occurs.
                                               strictly prohibited.






                 Training relevant personnel



















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