Recommissioning your water system
14 May 2020
Published in: Member News
This blog covers guidance on how you should recommission your water system before reopening your building
As per the guidance issued
by the Legionella Control Association (LCA) 13th May, 2020, it is
essential that when buildings reopen following the lifting of COVID-19
restrictions, that any water system is not simply put straight back into use. During
the period of shutdown, if flushing cannot be carried out weekly or twice
weekly dependant on the setting, it would be sensible to formulate a
recommissioning plan for each water system to allow safe start-up, and
assurance to users that it is safe and free of bacteria.
This article provides guidance to owners and
managers of premises regarding recommissioning of their water systems after a
period of shutdown. Now that the government is planning their steps to lift the
lockdown in a phased manner, it is important that duty holders take necessary steps
to make sure that their buildings are safe before they reopen.
The following points have been compiled by
referring to various guidance released by Gov.uk, LCA, Public Health England, and
the HSE in line with guidance documents including ACoP L8 and HSG 274.
Recommissioning of a building water
system can utilise various levels of intervention, and the level of work and
investment should be appropriate for the risk. For very simple buildings
flushing alone may be sufficient but for most buildings, some form of
disinfection is likely to be needed. In the worst cases, repeat disinfection
and extensive cleansing flushing may be required to clear contamination.
Evaporative cooling systems should already
have a robust start-up and shut-down procedures in place, and the expectation
is that these must be followed.
The minimum expectation for small, simple hot
and cold-water systems would be flushing through with fresh mains water. Larger
buildings, those with tanks, showers, calorifiers and more complex pipework the
expectation is likely to be for more extensive flushing, followed by cleaning
and disinfection. Additionally, temperature checks should be carried out to
ensure that the system controls are within tolerance.
COVID-19 water systems should not be drained down - HSG274 does not advocate
Where buildings have been empty for a period
of time and during warm weather, it is likely that some increase in bacteria
levels and biofilm will occur. These water systems may require more than
a simple disinfection to be successful.
In all cases where systems are being
recommissioned, it is sensible to have
evidence to prove/reassure that the recommissioning process has been effective.
Legionella sampling to BS7592 is recommended within recommissioning plans
to validate the effectiveness of the process.
dutyholders are not able to put in place a proper recommissioning process to
use the water system safely, they should not reopen the building. In
addition to legionella risk, drinking water retained within buildings may no
longer be potable following a period of prolonged stagnation.
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This is a basic guide to getting your water system back
to normal, however each water system depending on its complexity may require
additional work. Speak to your consultant for bespoke advice.
You should ensure that you have the following in place
during and after the COVID19 crisis:
documented risk assessment in place developed by persons who are experienced and
of the written scheme and risk assessment are implemented for the control of
flushing or treatment programmes based on equipment and manufacturer’s guidance
For more information:
LCA Guidance on reopening buildings
LCA Guidance during COVID 19
COVID 19 legionella guidance for dental surgeries
HSE guidance for schools
Want more bespoke advice and guidance? Speak to NANT's experts today!
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