Canada Occupational Health and Safety Regulations

8.20 (1) Work must not be performed on any electrical equipment in an area if the following devices are found unless the device is connected to a common grounding network:

• (a) a grounding bus,

• (b) a station grounding network,

• (c) a neutral conductor,

• (d) temporary phase grounding, or

• (e) a metal structure.

(2) If, after the connections are made, a safety ground is required to ensure the safety of an employee working on the electrical equipment, the safety ground shall be connected to the common grounding network.