The Ontario Building Code | Emergency Lighting
3.2.7.3. Emergency lighting="http://thehandyforce.com/electrical/" title ="East York Electrician">lighting
(1) Emergency lighting="http://thehandyforce.com/electrical/" title ="East York Electrician">lighting shall be provided to an average level of illumination not less than 10 lx at floor or tread level in,
(a) exits,
(b) principal routes providing access to exit in an open floor areaand in service rooms,
(c) corridors used by the public,
(d) corridors serving patients’ or residents’ sleeping rooms in a Group B, Division 2 or 3 occupancy,
(e) corridors serving classrooms,
(f) underground walkways,
(g) public corridors,
(h) floor areasor parts of them where the public may congregate in,
(i) Group A, Division 1 occupancies, or
(ii) Group A, Divisions 2 and 3 occupancies having an occupant load of 60 or more,
(i) floor areasor parts of them in day care centres where persons are cared for,
(j) food preparation areas in commercial kitchens,
(k) principal routes providing access to exit in a floor areathat is not subdivided into rooms or suites of rooms served by corridors in a business and personal services occupancy, a mercantile occupancy or an industrial occupancy, and
(l) internal corridors or aisles serving as principal routes to exits in a business and personal services occupancy, a mercantile occupancy or an industrial occupancy that is subdivided into rooms or suitesof rooms, and is not served by a public corridor.
(2) Emergency lighting="http://thehandyforce.com/electrical/" title ="East York Electrician">lighting to provide an average level of illumination of not less than 10 lx at floor or catwalk level shall be included,
(a) in a service space referred to in Sentence 3.2.1.1.(9), and
(b) on a shelf and rack storage system, in locations described in Sentence 3.16.1.5.(2).
(3) The minimum value of the illumination required by Sentences (1) and (2) shall not be less than 1 lx.
(4) In addition to the requirements of Sentences (1) to (3), the installation of battery-operated emergency lighting="http://thehandyforce.com/electrical/" title ="East York Electrician">lighting in health care facilities shall conform to the appropriate requirements of CSA Z32, "Electrical Safety and Essential Electrical Systems in Health Care Facilities".
In Plain Language
This clause requires transfer switches and wiring for emergency power systems to be arranged so backup power activates automatically and reliably without manual intervention when the normal supply fails.
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.