CEA 4001 - Water supplies

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E.2.6 Water pressures
Pipework, fittings, valves and other equipment shall be capable of withstanding the maximum pressure
likely to be encountered.
NOTE: to overcome the problem of pressures in excess of 12bar, hydraulic alarm gongs may be driven
via a pressure reducing valve or from a secondary water supply such as a town main,
controlled by a diaphragm valve connected to the main installation control valve alarm port.
E
E.3 Water supplies
E.3.1 Types of water supplies
The system shall have at least one superior single water supply.
E.3.2 Pressure and flow requirements for pre-calculated installations
The water supply shall be designed to achieve a minimum pressure and flow condition at the zone
subsidiary stop valve outlet as specified in Table 7, taking Ps to be the pressure difference equivalent to
the height of the highest sprinkler above the installation zone subsidiary stop valve.
E.3.3 Water supply characteristics for pre-calculated installations
The water supply characteristics shall be determined by a hydraulic calculation of the pipework upstream
of the zone subsidiary stop valve outlet, at the higher and lower flow rates specified in Table 7, and
shall include calculations at the water supply datum point.
E.3.4 Pump performance for pre-calculated installations
Automatic pumps shall have characteristics in accordance with Table 19.
NOTE: Pressures are taken at the pump outlet or the relevant stage of multi-stage pumps, on the
delivery side of any orifice plate.