Hong Kong Regulations

ELECTRICITY (WIRING) REGULATIONS - REGULATION 5

Segregation of circuit categories

(1) Category 1, 2, 3 and 4 circuits shall be segregated from one another as
far as is necessary to prevent danger and electrical interference.

(2) Category 4 circuits shall not be installed in the same conduit, ducting or
trunking as circuits of other categories and shall be segregated from circuits
of other categories at a distance sufficient to prevent danger and electrical
interference with the circuits of those other categories. (Enacted 1990)