ABSTRACT
This chapter includes byelaws concerned with the protection of all mains supplied water services from the risk of contamination arising from backflow. It provides definitions of backflow prevention devices. The first principle of protection is that mains supplied water is kept separate from any other water e.g. that supplied from a private source or non-potable water. The second principle is that there should be no cross connections within an installation, e.g. from a supply pipe to a distributing pipe, thus ensuring that potentially contaminated water in a distributing system cannot reach the supply pipe. The third principle is that protection against backflow should be afforded at every point of use be it a draw-off tap, a flushing cistern or a washing machine.
