Metal stud partitions do not require earthing, cables in them require 30 mA RCD protection.
701.401.3.6 distinguishes between serving the location and zones within a bathroom, in a bathroom or shower room you need 30 mA RCD protection for circuits:
(i) serving the location
(ii) passing through zones 1 and/or 2 not serving the location.
Metal stud partitions do not require earthing, cables in them require 30 mA RCD protection.
701.401.3.6 distinguishes between serving the location and zones within a bathroom, in a bathroom or shower room you need 30 mA RCD protection for circuits:
(i) serving the location
(ii) passing through zones 1 and/or 2 not serving the location.