Procedures are recommended for proper earthing in order to protect equipment, components and personnel from currents which can result from accidental contact with nearby energized conductors, or induced voltage from adjacent energized lines, lightning strikes, switching errors or electrostatic charging..
The equipment under consideration in this National Standard of Canada is used for distribution voltages, usually considered to be below 50 kV.
However for voltages of 50 kV and above, use of Standard CAN/ULC-61328-05 may be more appropriate. The choice of whether Standard CAN/ULC-61328-05 or this National Standard of Canada applies to the work being considered will usually depend on the physical size of the conductors, the size of the structures and the average span between supports.”