Page 629 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

Chapter 9 Sanitation systems

Blocked WCs
Again, a blocked WC can often be cleared using a special kind of force cup,
designed specifically to unblock WC pans and external gullies. It is known as a
WC plunger (Figure 9.114).

Blocked waste pipes
Blocked waste pipes can often be cleared by the use of a hand spinner
(Figure 9.115). An auger at the end of the hand spinner rotates as it enters the
waste pipe, breaking up the blockage on contact. Care must be taken if this tool p Figure 9.114 A WC plunger
is being used with push-fit waste systems to ensure the joints are not being
forced apart. Thorough testing should be conducted after use to make certain
that leaks have not been created.

4 THE PRINCIPLES OF GREY

WATER RECYCLING
p Figure 9.115 A hand spinner
Grey water KEY TERM

About a third of all water used in the average household is for WC flushing. Grey water: waste water
The grey water used for bathing from baths, showers and washbasins can be from baths, showers,
collected, cleaned and reused for this purpose. washing machines,
dishwashers and sinks.
Grey water is usually clean enough for use in WCs with only minimal disinfection
or micro-biological treatment. Problems can arise, however, when the warm
grey water is stored because it quickly deteriorates and the bacteria it contains
quickly multiply, making the water smell; this can be overcome by filtration and
treatment with chemicals. There must also be a means of protecting the mains
water against contamination by backflow from a grey water system in order to
comply with the Water Supply (Water Fittings) Regulations 1999.

Rainwater harvesting
Rainwater harvesting has the potential to save a large volume of mains water
and reduce pressure on resources because water that would otherwise be lost
can be used to flush toilets, to water gardens and feed washing machines,
instead of using water direct from the mains supply.

VALUES AND BEHAVIOURS

Water is a precious resource and rainwater harvesting is another means by
which we can minimise our impact on the environment.

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