This is the first edition of CSA Standard C22.3 No. 1, Overhead Systems and Underground Systems, written in SI (metric) units. It is one of a series of Standards issued under Part III of the Canadian Electrical Code and is intended to coexist with the 1976 edition, which is expressed in yard/pound units and which will remain in use, without revision, for an interim period. Metric conversion has been achieved within the tolerance of the yard/pound edition, so that either edition can be used for clearances and separations except for Table 3, which has increased clearances.
This Standard applies to the lines and equipment of electric supply and communication utilities located entirely outside of buildings and fenced supply stations.