Mechanical Protection for Electrical Cables

1) Where subject to mechanical damage, mineral-insulated cable, aluminum-sheathed cable, and copper-sheathed cable shall be suitably protected.

2) Where mineral-insulated cable, aluminum-sheathed cable, or copper-sheathed cable is installed on the face of a wall, partition, ceiling, or structural member within 1.5 m of the floor, and in all locations where subject to mechanical damage, as for instance from industrial tractors, other vehicles, equipment, stockpiling, or excessive vibration, a suitable safeguard against such damage shall be provided.


3) Mineral-insulated cable, aluminum-sheathed cable, or copper-sheathed cable shall be protected, located, or arranged so that a 2-1/2 inch common nail cannot be driven into it, where the cable is

a) run through bored or notched holes or grooves in wooden structural members;
b) secured directly to the underside of wooden flooring; or
c) located behind baseboards or casings.

4) In order to comply with Subrule 3), the hole, groove, or supporting strap containing the cable shall be permitted to be sufficiently oversized to permit the cable to move a distance equal to at least the radius of the cable.

5) Where mineral-insulated cable, aluminum-sheathed cable, or copper-sheathed cable passes from a point above grade to direct earth burial and is not otherwise protected against mechanical damage, a suitable pipe stub-up shall be arranged to encase the cable to a point, where practicable, at least 300 mm above grade and, in locations where frost heaving may occur, the encasement shall slide freely on the cable so as to avoid damage.

Source: Rule 12-710, CSA C22.1:21, Canadian Electrical Code, Part 1 (25th Edition), Safety Standard for Electrical Installations. © 2021 Canadian Standards Association. Please visit