Section 123(6) in The Indian Electricity Rules, 1956
(6)All flexible metallic screening or armouring specified in sub-rule (5) shall comply with the provisions of rule 122(d):Provided that in the case of separately screened flexible cables the conductance of each such screen shall not be less than 25 per cent of that the power conductor and the combined conductance of all such screens shall in no case be less than that of 0.15 sq. cm. copper conductors.
