Water Treatment
Pre-Commission Cleaning of Closed Water Systems
As commissioning engineers we are acutely aware of the need for good
water quality to achieve
accuracy in operation of balanced water
systems. System contaminants such as millscale, jointing
compounds and
building debris will inevitably be found in newly fabricated pipework
systems. If
allowed to remain in the system, these contaminants will
make the system prone to blockage at
strainers, control valves, regulating
valves and small bore heat exchangers. They may also initiate
further
corrosion and may encourage the growth of micro-organisms.
We have as a result developed the in-house capability to undertake the
pre- commission cleaning
of systems in accordance with BSRIA
Application Guide AG 1/2001.1 'Pre-Commission Cleaning of
Pipework
Systems'. This service is available to our customers as part of an
integrated programme
for cleaning and commissioning, or as a stand
alone package for flushing and cleaning of new and
existing pipework
systems.
Due to the problems that frequently occur from bacteriological
infestation of closed water systems,
arising from the construction
process, we can provide portable dosing rigs for attachment to the
incoming
water supply, to biocide treat all incoming water used for filling and
charging completed
pipe systems and also incorporate within the
flushing and cleaning, a biocide wash to remove any
bacterial filming
which may have occurred prior to filling the system.
We also have a selection of portable pump rigs, specially designed for
our purposes for use
where the system pumps are not available for
circulation of water during flushing and cleaning.
Sterilisation of Domestic Water Systems
We provide a service in respect of the disinfection of water services to BS6700:2006 Section Three, Paragraphs 1.10.3 to 4. This will involve the removal of all dirt and debris from storage tanks and all pipework thoroughly flushed with mains water followed by the introduction of a Sodium Hypochloride solution to a level of 50 mg/I of free chlorine, either directly into the storage tank or dosed under pressure into the mains pipework.
The chlorinated water is drawn through the complete system and allowed
to stand for not less than one hour, at the
end of which period the
residual free chlorine must not be less than 30 mg/I. The pipework is
then flushed thoroughly
until the residual chlorine level is no
greater than that present in the water entering the system.
After flushing a sample would be taken for independent bacteriological
analysis by a UKAS registered laboratory to certify that the
disinfection has been achieved.
Water Systems Maintenance Monitoring
Monitoring, inspection and sampling should be carried out on all domestic water and closed water systems at regular intervals, preferably within an established maintenance/control programme, based upon appropriate risk assessments, to confirm the maintained quality.
All bacterial samples are tested by independent UKAS accredited laboratories.