CSA - C22.3 NO. 7- 94
|Publication Date:||1 December 1994|
This Standard applies to the lines and equipment of electric and communication utilities located entirely outside buildings and fenced supply stations and designed for an operating voltage of not more than 150 kV phase to phase.
This Standard, which forms part of the Canadian Electdcal Code, Part Ili, covers the requirements for construction of underground systems and includes electric supply and communication circuits installed alone, in joint use, or in proximity to each other or other facilities
(a) crossing each other or other facilities;
(b) crossing under railways or highways; or
(c) under ground likely to be traversed by vehicles or pedestrians.
The requirements contained in this Standard do not constitute complete construction specifications but do stipulate the minimum design requirements that are most important from the viewpoints of
(a) safety to persons;
(b) continuity of service; and
(c) protection of property.
Conditions not covered herein shall be governed by the appropriate requirements or equivalent Standards in common use, or as required by constituted authority.
In this Standard specific types of construction are envisaged. This does not preclude the use of other types of construction arising out of continuing development, provided the engineering representatives of the party or parties involved have evidence as to their safety and suitability.
An example of such a development is the surface channel system, which is described in Appendix C. The material presented there is for engineering information only and does not form a mandatory part of this Standard.
The use in the Standard of terms such as "where practicable" is not intended to provide an opportunity or an excuse for not meeting the minimum requirements called for, but to indicate the preferred separation or action. When an alternative is not stated, the engineering solution that most closely approximates the preferred action in the circumstances is to be used. When more than one rule applies, all must be satisfied.