Page 10 - Water_Controls_for_Healthcare

/ Water quality regulations

EUROPEAN WATER QUALITY REGULATIONS

Regular flush Removable mixers and taps
According to the French, German and English In addition to preventative measures, the HSE (Health
regulations, water stagnation (in sanitary installations and Safety Executive) recommends the use of mixers
and mixers and taps) is a key factor in bacterial and taps that can be easily removed for regular
contamination. internal cleaning; a mechanical intervention
The European standard EN 806 5 requires that that is effective for removing biofilm.
those sections of the installation that are used
Stagnation prohibited infrequently should be flushed at regular intervals. Circulating loops
The recommended interval is once a week. A circulating loop up to the point-of-use is not
All public and commercial buildings are affected, recommended. It doubles the length of the pipework
in particular schools and council buildings during and therefore doubles the water volume. The biofilm
the school holidays, campsites out of season, surface is increased and, as a result, the risk of
unoccupied hospital rooms, etc.
bacterial development. Moreover, it makes it difficult
to maintain high temperatures at all points in the
The German directive of September 2023, Hygiene
in Drinking Water Installations VDI 6023 Blatt, circulating loop.
requires purging to be carried out after 72 hours of
stagnation in a sanitary installation (this also includes A circulating loop up to the point-
WC cisterns). Note that the water in the bypass is not of-use is not recommended.
Bypass prohibited sufficiently renewed. They are therefore prohibited.
If an installation is not used for 72 hours, rigorous
protocols are put in place. DELABIE sees this as
a step forward and proposes technical solutions Finally, it also makes it difficult to keep the pipe run
to meet this requirement (see opposite: electronic volume to less than the 3 litres recommended by
controls). European directives. Indeed, if the water temperature
in a circulating loop is less than 50°C or 55°C
The German directive requires (depending on the country), the water volume
in the circulating loop must be included
purging to be carried out after
in the 3-litre maximum calculation.
72 hours of stagnation.
In the UK, where there is a high risk of scalding,
Measuring pressure
thermostatic mixing valves (TMVs) must be fitted.
Undersized pipework The HSE guidance recommends keeping pipe runs
The German regulation strictly prohibits oversized between a thermostatic mixing valve (TMV) and the
pipework because it promotes bacterial growth outlet as short as possible, and the pipe run should
by reducing the water velocity. not exceed 2 metres. Where practicable, the TMV
DELABIE, along the same lines, recommends slightly should be incorporated within the tap.
decreasing the diameter of the pipes to increase
the water velocity to 2m/sec. (likewise the French Infection Control
regulation (DTU) recommends 1.5m/sec.). NHS Estates Technical Bulletin No. 2024/3,
This measure prevents the excessive development of published on 27 August 2024, provides guidance
biofilm and helps to reduce the risk of contamination to improve water safety in healthcare environments,
without increasing noise levels.
Measuring the temperature with a focus on preventing infections caused by
waterborne pathogens such as non-tuberculous
Oversized pipes mycobacteria (NTM).
are strictly prohibited. The bulletin highlights the importance of
implementing specific measures, including careful
water temperature control and reducing stagnation,
to minimise the risk of infection in showers and taps,
Training
Understanding the problems associated with particularly for vulnerable patients.
bacterial growth in water systems helps to limit In addition, it recommends that thermostatic mixers
the risk of contamination. no longer be water tested to avoid any stagnation of
Although French legislators have not yet focused water in the tap body and therefore prevent bacterial
on training those responsible for the water system, growth. At DELABIE, leak tests are carried out using
Training relevant personnel air as standard in full compliance with the Technical
it is embedded and pursued in Germany
(with three training levels, depending on the level Bulletin.
of responsibility) and in the United Kingdom
(with personnel competency and training Building Management Systems
programmes monitored by the Water Safety Group). Contrary to popular belief, Building Management
Systems are not recommended by European
Training those responsible helps directives as they can be complicated, difficult to
handle and extremely costly and do not take away
to control bacterial proliferation. liability if a problem occurs.

8 Hospital solutions