The Ontario Building Code | Protection of Fire Escapes
3.4.7.4. Protection of Fire Escapes
(1) If a fire escape serves any storey above the second, openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings located in a zone described in Sentence (2), including access doorway ="http://thehandyforce.com/doors/" title ="Toronto Door installer">doorways in the exterior walls of the buildingto which the fire escape is attached, shall be protected by closures conforming to Subsection 3.1.8.
(2) The zone referred to in Sentence (1) extends from any balcony, platform or stairway of a fire escape to a distance,
(a) 3 m horizontally,
(b) 10 m below, and
(c) 1 800 mm above.