The Ontario Building Code | Guards and Railings
3.4.7.6. Guards and Railings
(1) The open sides of every platform, balcony and stairway forming part of a fire escape shall be protected by guards not less than 920 mm high measured vertically above the nosing of any tread or platform.
(2) The top rail of a guard is permitted to serve as a handrail if it is free from obstructions that could break a handhold.
(3) A wall handrail shall be installed if the fire escape is more than 550 mm wide.
(4) openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings through any guard that is required by Sentence (1) shall be of a size that will prevent the passage of a sphere having a diameter more than 100 mm unless it can be shown that the location and size of openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings that exceed this limit do not represent a hazard.
(5) Unless it can be shown that the location and size of openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings do not present a hazard, a guard for a fire escape shall be designed so that no member, attachment or opening located between 140 mm and 900 mm above a platform or the nosing of any tread will facilitate climbing.
In Plain Language
The open sides of a fire escape's platforms, balconies, and stairways need guards at least 920 mm high, and the guard's top rail can double as a handrail if it's free of obstructions that could break someone's grip.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.