(1) All conductors used within the building shaJI be of tinned copper having a conductivity equal to not less than 90 per cent, of pure copper and shall be so proportioned that the current density in any conductor sball not exceed 155-amps. per square centimeter·
Provided that, in the case of a Janata Cinema, the use of aluminum conductors having a conductivity equal to that of tinned copper conducto~ shall be considered sufficient for the purpose of this rule.
(2) Where a number of lights, as in the footlights. battens, etc., are supplied under control of the switch and protected by a single or double pole cut-out, as the case may be, the conductor shall be maintained through out of such se,..tions that will be effectually protected by the cut-outs against heating.