(1) All conductors including lead covered cables where accessible to the public shall be efficiency protected from mechanical injury by an external armour of iron or steel .
(2) Where conductors pass through or within walls f ire -proof floors or ceil ing, they shall be protected by iron pipes or by glazed stoneware or porcelain tubes and 22 precautions shall be taken to prevent the possibil i ty of f ire water passing along the course of the conductors.
(3) Conductors shall not be placed where l iable to be heated by jets, steam pipes or other appliances.
(4) In special cases, or where necessary for protection from the depredations of rats, mice or other vermin, the wiring shall be enclosed in heavy gauge steel conduit .