3. Every water fitting shall–
(a)be immune to or protected from corrosion by galvanic action or by any other process which is likely to result in contamination or waste of water; and
(b)be constructed of materials of such strength and thickness as to resist damage from any external load, vibration, stress or settlement, pressure surges, or temperature fluctuation to which it is likely to be subjected.
4. Every water fitting shall–
(a)be watertight;
(b)be so constructed and installed as to–
(i)prevent ingress by contaminants, and
(ii)inhibit damage by freezing or any other cause;
(c)be so installed as to minimise the risk of permeation by, or deterioration from contact with, any substance which may cause contamination; and
(d)be adequately supported.
5. Every water fitting shall be capable of withstanding an internal water pressure not less than 1½ times the maximum pressure to which that fitting is designed to be subjected in operation.
6. No water fitting shall be installed, connected or used which is likely to have a detrimental effect on the quality or pressure of water in a water main or other pipe of a water undertaker.
7.—(1) No water fitting shall be embedded in any wall or solid floor.
(2) No fitting which is designed to be operated or maintained, whether manually or electronically, or which consists of a joint, shall be a concealed water fitting.
(3) Any concealed water fitting or mechanical backflow prevention device, not being a terminal fitting, shall be made of gunmetal, or another material resistant to dezincification.
(4) Any water fitting laid below ground level shall have a depth of cover sufficient to prevent water freezing in the fitting.
(5) In this paragraph “concealed water fitting” means a water fitting which–
(a)is installed below ground;
(b)passes through or under any wall, footing or foundation;
(c)is enclosed in any chase or duct; or
(d)is in any other position which is inaccessible or renders access difficult.