Overhead systems

Note: The standard designation number for this NOI (originally published on August 18, 2020), was updated by the responsible SDO on November 9, 2021.

1.1
This Standard applies to electric supply and communication lines and equipment located entirely outside of buildings and fenced supply stations.

1.2
Existing installations (including maintenance replacements and maintenance alterations) meeting the original designs that currently comply with prior editions of this Standard, need not be modified to comply with this edition of the Standard, except as might be required for safety reasons by the authority having jurisdiction.

1.3
This Standard, which forms part of the Canadian Electrical Code, Part III, provides requirements for the construction of overhead systems. It covers electric supply and communication circuits that

a) are installed alone;
b) are in joint use;
c) are in proximity to each other or other facilities;
d) cross each other or other facilities; and
e) cross railways, highways, navigable waterways, or land that is likely to be traversed by vehicles or pedestrians.

1.4
This Standard presents a choice between deterministic and reliability-based design methods. Reliability-based design methods are covered by CSA C22.3 No. 60826.

1.5
The requirements contained in this Standard do not constitute complete design and construction specifications, but rather prescribe the minimum design requirements that are most important to the

a) safety of persons;
b) continuity of service; and
c) protection of property.

1.6
Conditions not covered by this Standard are governed by equivalent Standards in common use or by the authority having jurisdiction.

1.7
In some cases in this Standard, specific types of construction are envisaged. This does not preclude the use of other types of construction, provided that the engineering representatives involved can demonstrate the safety and suitability of these alternatives.

1.8
The use of terms such as "where practicable" is not intended to provide an opportunity for not meeting the requirements of this Standard, but indicates the preferred clearance or method. Where an alternative is not specified, the engineering solution that most closely adheres to the preferred method should be used.

1.9
Where the requirements of more than one clause apply, all should be satisfied.

1.10
In this Standard, "shall" is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; "should" is used to express a recommendation or that which is advised but not required; and "may" is used to express an option or that which is permissible within the limits of the Standard.

Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.

Notes to tables and figures are considered part of the table or figure and may be written as requirements.

Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.