Canadian Aviation Regulations
601.23 (1) For the purposes of this Division, any building, structure or object, including any addition to it, constitutes an obstacle to air navigation if
(a) it penetrates an airport obstacle limitation surface as calculated in Chapter 4 of the Standard entitled Aerodrome Standards and Recommended Practices, TP 312E, published by the Department of Transport;
(b) it is higher than 90 m AGL and is located within 6 km of the geographical centre of an aerodrome;
(c) it is higher than 90 m AGL and is located within 3.7 km of the centreline of a recognized VFR route, including, but not limited to, a valley, a railway track, a transmission line, a pipeline, a river and a highway;
(d) it is higher than 150 m AGL; or
(e) in the case of any catenary wires crossing over a river, any portion of the wires or supporting structures is higher than 90 m AGL.
(2) For the purposes of subsection (1), an addition to a building, structure or object includes any vertical mast, pole, tower or other object erected on top of the building, structure or object and adding to its height.
- SOR/2011-285, s. 6
- Date modified: