17. All supplier’s works shall be sufficient for the purposes for, and the circumstances in, which they are used and so constructed, installed, protected (both electrically and mechanically), used, and maintained as to prevent danger or interruption of supply so far as is reasonably practicable.
18. No electric line shall be used for the purpose of supply at a voltage greater than 440,000 volts.
19. The supplier shall take precautions to prevent, so far as is reasonably practicable, danger due to the influx of water or any noxious or explosive liquid or gas into any enclosed space containing his works.
20.—(1) Paragraphs (2) and (3) shall apply only to supplier’s works where energy at high voltage is generated, transformed, converted, regulated, switched or controlled.
(2) The supplier shall—
(a)enclose any part of a substation in the open air, containing live apparatus which is not encased, by a fence not less than 2.4 metres high to prevent, so far as is reasonably practicable, danger or unauthorised access;
(b)ensure that, So far as is reasonably practicable, there are at all times displayed in a conspicuous position—
(i)subject to paragraph (3), a safety sign and a notice giving the name of the supplier and an address or telephone number where a person appointed by the supplier will be in constant attendance, and
(ii)such other signs as may be necessary to give warning of danger having regard, inter alia, to the siting of, the nature of, and the measures taken to ensure the physical security of, the supplier’s works; and
(c)take all reasonable precautions to minimise the risk of fire.
(3) The provisions of paragraph (2)(b)(i) shall not apply to any exposed live parts of the supplier’s works which are held at least 4.3 metres above ground by a support, or to any insulated electric line attached to that support.
21. The supplier shall apply protective devices to every system which will, so far as is reasonably practicable, prevent any current, including leakage to earth, from flowing in any part of a system for such a period that that part of the system can no longer carry that current without danger.
22. The supplier shall make arrangements which ensure, so far as is reasonably practicable, that—
(a)every low voltage electric line shall be protected against danger arising from accidental contact with or leakage from any high voltage electric line; and
(b)where energy at a higher voltage is transformed no danger shall be caused as a result of a system at a lower voltage becoming charged above its normal voltage by leakage from or contact with the supplier’s system at the higher voltage.
23.—(1) The supplier’s works shall be so arranged, and provided where necessary with fusible cut-outs or automatic switching devices so located as to restrict, so far as is reasonably practicable, the number of consumers affected by any fault in the supplier’s works.
(2) The supplier shall at all times take all reasonably practicable steps to avoid interruptions of supply resulting from his own acts.
24. The supplier shall take all reasonably practicable steps to inspect his installations and works to ensure compliance with these Regulations.