1989 Ed.]
Waterworks Regulations
[CAP. 102
A 29
[Subsidiary]
7.
Pipes used for conveying hot water shall be of galvanized steel, galvanized wrought iron, copper, or of some corrosion-resisting alloy:
Provided that cast iron pipes of not less than 50 mm internal diameter may be used if suitable provision for their expansion is made.
8.
9.
Every hot water cylinder or tank of a capacity of not less than 100 litres shall---
(a) if made of mild steel, comply with the requirements for cylinders or tanks, as the case may be, of BS 417, Part 2 for galvanized mild steel cisterns, tanks and cylinders or with BS 1565, Part 2 for galvanized mild steel indirect cylinders; and
(b) if made of copper, comply with BS 699 for copper cylinders for domestic purposes or with BS 1566, Parts 1 and 2 for copper indirect cylinders.
Every water heater of thermal storage type or the calorifier type shall comply with the requirements of BS 843 for stationary non-instantaneous electric water heater or with BS 853 for hot water calorifiers respectively.
10. Every water heater burning gas shall comply with BS 1250: (Part 1 and Part 3) for domestic appliances burning gas.
(L.N. 252 of 1977)
PART V
FLUSHING APPARATUS
1. Every flushing cistern shall be of the valveless syphonic type unless otherwise approved by the Water Authority. A stop valve shall be fixed in a readily accessible position so as to control the supply to the cistern.
2.
Flushing cisterns for water-closet fitments and slop sinks shall be capable of giving a flush of not less than 9 litres and not more than 15 litres of water on each occasion such fitment is used.
3.
The capacity of the flushing cistern in the case of trough water-closets and urinals shall be approved by the Water Authority subject to the discharge in the case of trough water-closets being not less than 9 litres of water for every metre of the channel and the discharge in the case of urinals being not less than 4.5 litres of water for every basin or stall, or in the case of a trough urinal, every metre thereof.
4. The internal diameter of flushing pipes shall-
5.
(a) in the case of water-closet fitments, trough water-closets and slop sinks, be not less than 30 mm;
(b) in the case of urinals (other than trough urinals), be not less than 15 mm for each basin and stall; and
(c) in the case of trough urinals, be not less than 15 mm for every metre thereof.
Every flushing apparatus shall be operated by hand, except in cases where written permission from the Water Authority has been granted for the installation of automatic flushing. In such cases the method of control and the amount and frequency of the flushes shall be decided by the Water Authority.
6. Every flushing cistern operated by hand shall be provided with a ball valve so arranged as to refill the cistern within 2 minutes.
7.
Flushing cisterns shall in all cases be supplied from storage cisterns and such storage cisterns shall not be used to supply any other apparatus, appliance or fitting. Every such cistern shall be fitted with a suitable close fitting cover and provided with adequate access to enable the cistern to be entered and cleaned.
8. Every flushing cistern shall have an overflow which shall discharge in a conspicuous position.
9. Flushing apparatus without flushing cisterns shall not be used.
(L.N. 252 of 1977)