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


















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